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AL1665S-13
LED, AC/DC DRIVER, SOIC, SMD
⚠️ Reference pricing provided. In case of supply shortages, we will connect you with our trusted procurement partners to ensure your project's continuity.
- Manufacturer: DIODES INC.
- Product type: AC / DC LED Driver ICs
- SVHC: No SVHC (25-Jun-2025)
- Topology: Buck-Boost, Flyback
- IC Mounting: Surface Mount
- No. of Pins: 8Pins
- Product Range: -
- Qualification: -
- No. of Outputs: 1Outputs
- Device Topology: Buck-Boost, Flyback
- LED Driver Type: Isolated
- Driver Case Style: SOIC
- IC Case / Package: SOIC
- Input Voltage Max: 305V
- Input Voltage Min: 85V
- Output Current Max: -
- Output Voltage Max: 20V
- Switching Frequency: -
- Switching Frequency Typ: 150kHz
- Operating Temperature Max: 105°C
- Operating Temperature Min: -40°C
- Automotive Qualification Standard: -
| Delivery and price | |
|---|---|
| Units per pack | 500 |
| Price | 0.177 € |
| Current stock | 500+ |
| Lead time | 30 days |
Datasheet
**AL1665**
## **HIGH PERFORMANCE DIMMABLE LED CONTROLLER**
## **Description**
The AL1665 is a high-performance single-stage flyback and buckboost controller, targeting dimmable LED lighting application. It is a primary side regulation (PSR) controller that can provide accurate constant current (CC) regulation without optocoupler and secondary control circuitry. It can be operated at BCM mode, which results in low EMI and high efficiency, and keeps high power factor (PF) and low total harmonic distortion (THD) under universal input voltage.
The AL1665 can support analog/PWM dimming modes. When a 50mV to 2.5V DC signal is applied on ADIM pin, the device is operated in analog dimming mode. The analog dimming range is 5% to 100%. When a PWM signal is applied to NTC/PWM pin, the device is operated at PWM dimming mode. The PWM dimming range is 0.5% to 100% (1k PWM dimming frequency).
## **Pin Assignments**
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**----- Start of picture text -----**<br>
(Top View)<br>ADIM 1 8 FB<br>|| |<br>NTC/PWM || 2 7 VCC<br>COMP | 3 | 6 OUT<br>CS | 4 || 5 GND<br> SO-8 (Standard)<br>**----- End of picture text -----**<br>
The AL1665 has full protection features. It integrates multiple protections including undervoltage lockout (UVLO), output overvoltage (OVP), output short circuit (OSP), overcurrent protection (OCP), winding short circuit, secondary diode short, internal thermal foldback (TFP), and overtemperature protection (OTP).
The AL1665 is available in SO-8 (Standard) package.
## **Features**
- Primary Side Regulation without Optocoupler
- Valley Switching for Low Switching Loss
- Tight CS Reference Voltage 0.4V±1.5%
- High PF>0.9 and Low THD<20%
## **Applications**
- General LED Lighting Driver with Dimming Function
- General Purpose Constant Current Source
- LED Backlighting Driver
- Smart LED Lighting
- Support Analog and PWM Dimming
- Analog Dimming Range: 5% to 100%
- PWM Dimming Range: 0.5% to 100% (1k PWM Frequency)
- Internal Protections
- Undervoltage Lockout (UVLO)
- Output Overvoltage Protection (OVP)
- Output Short Protection (OSP)
- Overcurrent Protection (OCP)
- Winding Short-Circuit Protection
- Secondary Diode Short Protection
- Shorted Current Sense Protection
- User Programmable NTC Based Thermal Foldback
- Internal Thermal Foldback Protection (TFP)
- Overtemperature Protection (OTP)
- Tight LED Current Variation Range
- LED Current Line Regulation: ±2%
- LED Current Load Regulation: ±2% Full Load to Half Load
- Tight Output Open Voltage Variation Range
- Package: SO-8 (Standard)
- **Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)**
- **Halogen and Antimony Free. “Green” Device (Note 3** )
- **For automotive applications requiring specific change control (i.e. parts qualified to AEC-Q100/101/200, PPAP capable, and manufactured in IATF 16949 certified facilities), please contact us or your local Diodes representative.**
**https://www.diodes.com/quality/product-definitions/**
- Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant.
2. See https://www.diodes.com/quality/lead-free/ for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green" and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and <1000ppm antimony compounds.
1 of 17 **www.diodes.com**
AL1665 Document number: DS41772 Rev. 3 - 2
March 2020
© Diodes Incorporated
**AL1665**
**Typical Applications Circuit**
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C7 R14<br>L1 T1<br>C1 C2 RTH R10 C5 D3 R11 C6 + OUT<br>F1<br>AC VR1 D2<br>Input ti f Aux R4 D1 1 ; sa mi<br>DB1<br>Cvcc<br>R5 VCC ADIM D4<br>Q1<br>FB OUT<br>AL1665 R9<br>R6 COMP<br>Rcomp NTC/PWM GND CS<br>U1<br>Ccomp NTC RCS<br>Pet ae<br>Flyback Application Circuit<br>L1<br>C1 C2 RTH T1 R11 C6 OUT<br>F1 He<br>D3<br>AC<br>VR1<br>Input lano ee. Aux R4 D1<br>DB1<br>Cvcc<br>D4<br>R5<br>VCC ADIM<br>Q1<br>FB OUT<br>AL1665 R9<br>R6 COMP<br>Rcomp NTC/PWM GND CS<br>Ccomp NTC RCS<br>te<br>Buck-Boost Application Circuit<br>+<br>**----- End of picture text -----**<br>
## **Pin Descriptions**
|**Pin Descriptionsptionstions**|||
|---|---|---|
|**Pin Number**|**Pin Name**|**Function**|
|1|ADIM|Analog Dimming Input Pin|
|2|NTC/PWM|NTC Input Pin for Thermal Foldback/PWM Dimming Input Pin|
|3|COMP|Loop Compensation Pin|
|4|CS|Current Sense Pin, Connect This Pin to the Source of the Primary Switch|
|5|GND|Ground|
|6|OUT|Gate Driver Output|
|7|VCC|Supply Voltage of Gate Driver and Control Circuits of the IC|
|8|FB|The Feedback Voltage Sensing from the Auxiliary Winding|
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AL1665 Document number: DS41772 Rev. 3 - 2
March 2020 © Diodes Incorporated
**AL1665**
## **Functional Block Diagram**
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**----- Start of picture text -----**<br>
ADIM VCC<br>1 7<br>Thermal<br>NTC/ 2 Foldback & Analog VREF<br>Dim<br>PWM PWM Dim Control UVLO VREF<br>&Bias<br>TFP<br>OVP<br>6<br>FB 8 Valley ControlLogical Driver OUT<br>Detector<br>OTP<br>2V<br>-<br>OCP<br>+ Internal<br>OTP<br>Temperature<br>Sense<br>CS 4 - { _<br>Gm<br>+<br>VREF<br>3 5<br>COMP GND<br>**----- End of picture text -----**<br>
## **Absolute Maximum Ratings** (@TA = +25°C, unless otherwise specified.) (Note 4)
|**Symbol**|**Parameter**|**Rating**|**Unit**|
|---|---|---|---|
|VCC<br>~~es~~|Power Supply Voltage<br>~~es~~|-0.3 to 30<br>~~es~~|V<br>~~es~~|
|VCS<br>~~es~~|Voltage at CS to GND<br>~~es~~|-0.3 to 7<br>~~es~~|V<br>~~es~~|
|VFB<br>~~es~~|FB Input Voltage<br>~~es~~|-0.3 to 7<br>~~es~~|V<br>~~es~~|
|VCOMP<br>~~es~~|Voltage at Loop Compensation Pin<br>~~es~~|-0.3 to 7<br>~~es~~|V<br>~~es~~|
|VOUT<br>~~es~~|Driver Output Voltage<br>~~es~~|-0.3 to 20<br>~~es~~|V<br>~~es~~|
|VNTC/PWM<br>~~es~~|Voltage at NTC/PWM to GND<br>~~es~~|-0.3 to 7<br>~~es~~|V<br>~~es~~|
|VADIM<br>~~es~~<br>~~es~~|Voltage at ADIM to GND<br>~~es~~<br>~~Ge~~<br>|-0.3 to 7<br>~~es~~|V<br>~~es~~|
|TJ<br>~~es~~<br>~~es es~~|Operating Junction Temperature<br>~~es~~<br>~~Ge~~<br>~~es~~|-40 to +150<br>~~es~~|°C<br>~~es~~|
|TSTG<br>~~es es~~|Storage Temperature<br>~~Ge~~<br>~~es~~|-65 to +150|°C|
|TLEAD<br>~~es es~~<br>~~es~~|Lead Temperature (Soldering, 10s)<br>~~Ge~~<br>~~es~~<br>~~es~~|+300<br>~~es~~|°C<br>~~es~~|
|PD<br>~~es~~|Power Dissipation at TA= +50°C<br>~~es~~<br>~~Ge~~|0.65<br>~~es~~|W<br>~~es~~|
|ϴJA<br>~~es~~|Thermal Resistance (Junction to Ambient)<br>~~es~~<br>~~Ge~~<br>~~Ge~~|136<br>~~es~~|°C/W<br>~~es~~|
|ϴJC<br>~~es~~|Thermal Resistance (Junction to Case)<br>~~Ge~~<br>~~es~~<br>~~Ge~~|30<br>~~es~~|°C/W<br>~~es~~|
|—<br>~~pe~~|ESD (Human Body Model)<br>~~Ge~~<br>~~pe~~|2000<br>~~pe~~|V<br>~~—~~|
||ESD (Charged-Device Model)<br>~~pe~~|1000<br>~~pe~~|V<br>~~—~~|
Note: 4. Stresses greater than those listed under _Absolute Maximum Ratings_ can cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under _Recommended Operating Conditions_ is not implied. Exposure to _Absolute Maximum Ratings_ for extended periods can affect device reliability. All voltages unless otherwise stated are measured with respect to GND.
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AL1665 Document number: DS41772 Rev. 3 - 2
March 2020
© Diodes Incorporated
**AL1665**
## **Recommended Operating Conditions** (@TA = +25°C, unless otherwise specified.)
|**Symbol**|**Parameter**|**Min**|**Max**|
|---|---|---|---|
|TA|Ambient Temperature (Note 5)|-40|+105|
|VCC|Operating VCC Voltage (Note 6)|8.5|VCC_OVP(Min)|
Notes: 5. The device may operate normally at +125°C ambient temperature under the condition not triggers temperature protection. 6. ICC should be limited less than 5mA.
## **Electrical Characteristics** (@TA = +25°C, unless otherwise specified.)
|**Symbol**<br>~~a~~|**Parameter**<br>~~a~~|**Conditions**<br>~~a~~|**Min**<br>~~a~~|**Typ**<br>~~a~~|**Max**<br>~~a~~|**Unit**<br>~~a~~|
|---|---|---|---|---|---|---|
|**UVLO Section**<br>~~EE~~<br>~~LLLLLo~~<br>~~oT~~|||||||
|VCC_TH<br>~~LL~~<br>~~oT~~<br>~~I~~|Startup Threshold Voltage<br>~~LL~~<br>~~TF~~<br>|—<br>~~LL~~<br>~~TF~~<br>~~TTT LLL~~<br>|15.8<br>~~LL~~<br>~~LLL~~<br>|18.5<br>~~LL~~<br>~~LL~~<br>~~LLL~~<br>|19.5<br>~~LL~~<br>~~LL~~<br>~~LLL~~<br>|V<br>~~LL~~<br>~~Lo~~<br>~~LLL~~<br>|
|VOPR_MIN<br>~~oT~~<br>~~I~~|Minimal Operating Voltage<br>~~TF~~<br>|After Turn On<br>~~TF~~<br>~~TTT LLL~~<br>|5.8<br>~~LLL~~<br>|7.8<br>~~LL~~<br>~~LLL~~<br>|9<br>~~LL~~<br>~~LLL~~<br><br>~~LLL~~|V<br>~~Lo~~<br>~~LLL~~<br><br>~~LLL~~|
|VCC_OVP<br>~~oT~~<br>~~I~~|VCCOVP Voltage<br>~~TF~~<br>~~LL~~|—<br>~~TF~~<br>~~TTT LLL~~<br>~~LL~~|21.8<br>~~LLL~~<br>~~LL~~|25<br>~~LL ~~<br>~~LLL~~<br>~~LL~~|29.5<br> ~~LL ~~<br>~~LLL~~<br>~~LL~~<br>~~LLL~~|V<br> ~~Lo~~<br>~~LLL~~<br>~~LL~~<br>~~LLL~~|
|**Standby Current Section**<br>~~LLL~~<br>~~LE~~<br>~~eeee~~<br>~~es~~<br>~~es~~|||||||
|IST<br>~~ee~~<br>~~es~~<br>~~a~~|Startup Current<br>~~ee~~<br>|VCC= VCC_TH-0.5V,<br>Before Start Up<br>~~ee~~<br><br>~~Gs ts~~|—<br>~~ee~~<br>~~es~~<br><br>~~ts~~|120<br>~~ee~~<br><br>~~te~~|300<br>~~ee~~<br>|µA<br>~~ee~~<br>|
|ICC<br>~~ee~~<br>~~es~~<br>~~a~~|Operating Current @ 4KHz<br>~~ee~~<br>~~es~~|VCC=20V, VDIM=3V,<br>VFB=VCS=VCOMP=1V, COUT=1nF<br>~~ee~~<br>~~es~~<br>~~Gs ts~~|—<br>~~ee~~<br>~~es~~<br>~~es~~<br>~~ts~~|1<br>~~ee~~<br>~~es~~<br>~~te~~|2<br>~~ee~~<br>~~es~~|mA<br>~~ee~~<br>~~es~~|
|ICC_OVP<br>~~es~~<br>~~a~~|Shunt Current in OVP Mode<br><br>~~a~~|VCC> VCC_OVP<br><br>~~Gs ts~~<br>~~CG~~|3.1<br>~~es~~<br><br>~~ts ~~<br>~~CG~~|—<br><br> ~~te~~<br>~~CG~~|—<br>|mA<br>|
|**Drive Output Section**<br>~~TT~~<br>~~LLLLLo~~|||||||
|tR<br>~~LL~~|Output Voltage Rise Time (Note 7)<br>~~LL~~|CL= 1nF<br>~~LL~~|—<br>~~LL~~|100<br>~~LL~~<br>~~LL~~<br>~~LLL~~|—<br>~~LL~~<br>~~LL~~<br>~~LLL~~|ns<br>~~LL~~<br>~~Lo~~<br>~~LL~~|
|tF<br>~~Ln~~<br>~~Ee~~|Output Voltage Fall Time (Note 7)<br>~~Ln~~|CL= 1nF<br>~~Ln~~|—<br>~~Ln~~|100<br>~~LL ~~<br>~~Ln~~<br>~~LLL~~<br>~~LL~~|—<br> ~~LL ~~<br>~~Ln~~<br>~~LLL~~<br>~~LLL~~|ns<br> ~~Lo~~<br>~~Ln~~<br>~~LL~~<br>~~LL~~|
|VOUT_CLAMP<br>~~Ln~~<br>~~Ee~~|Output Clamp Voltage<br>~~Ln~~|VCC= 20V<br>~~Ln~~|9.8<br>~~Ln~~|12<br>~~LLL~~<br>~~Ln~~<br>~~LL~~|15.5<br>~~LLL ~~<br>~~Ln~~<br>~~LLL~~|V<br> ~~LL~~<br>~~Ln~~<br>~~LL~~|
|tON_MIN<br>~~Ee~~|Minimum On Time (Note 7)<br>~~a~~|—<br>~~OG~~|—<br>~~OG~~|1000<br>~~LL~~<br>~~OG~~|2010<br>~~LLL~~|ns<br>~~LL~~|
|tON_MAX<br>~~Ee~~<br>~~a~~<br>~~TT~~|Maximum On Time<br>~~a~~<br>|—<br>~~CO~~<br>|—<br>~~CO~~<br>|15<br>~~LL ~~<br>~~CO~~<br>~~**L**LL~~<br>|—<br> ~~LLL ~~<br>~~LL~~<br>|µs<br> ~~LL~~<br>~~LL~~<br>|
|tOFF_MAX<br>~~Ln~~<br>~~TT~~|Maximum Off Time<br>~~Ln~~<br>|—<br>~~Ln~~<br>|—<br>~~Ln~~<br>|290<br>~~Ln~~<br>~~**L**LL~~<br><br>~~L~~|405<br>~~Ln~~<br>~~LL~~<br><br>~~LLL~~|µs<br>~~Ln~~<br>~~LL~~<br><br>~~LLL~~|
|fMAX<br>~~TT~~|Maximum Frequency<br>~~TL~~|—<br>~~TL~~|—<br>~~TL~~|150<br>~~**L**LL~~<br>~~TL~~<br>~~L~~|—<br>~~LL~~<br>~~TL~~<br>~~LLL~~|kHz<br>~~LL~~<br>~~TL~~<br>~~LLL~~|
|**Internal CS Reference**<br>~~**L**LL LL~~<br>~~TT~~<br>~~L LLL~~<br>~~LL~~<br>~~LLLLLo~~|||||||
|VREF<br>~~LL~~|Internal Reference Voltage<br>~~LL~~|—<br>~~LL~~|0.394<br>~~LL~~|0.4<br>~~LL~~<br>~~LL~~<br>~~LL~~|0.406<br>~~LL~~<br>~~LL~~<br>~~LLL~~|V<br>~~LL~~<br>~~Lo~~<br>~~LLL~~|
|VCS_CLAMP<br>~~Ln~~|Primary Current Clamp Voltage<br>~~Ln~~|—<br>~~Ln~~|—<br>~~Ln~~|2<br>~~LL ~~<br>~~Ln~~<br>~~LL~~|—<br> ~~LL ~~<br>~~Ln~~<br>~~LLL~~<br>~~LLL~~|V<br> ~~Lo~~<br>~~Ln~~<br>~~LLL~~<br>~~LLL~~|
|VCS_OCP<br>~~LL~~|Primary Overcurrent Voltage<br>~~LL~~|—<br>~~LL~~|—<br>~~LL~~|3<br>~~LL ~~<br>~~LL~~|—<br> ~~LLL~~<br>~~LL~~<br>~~LLL~~|V<br>~~LLL~~<br>~~LL~~<br>~~LLL~~|
|**Error Amplifier**<br>~~LLL~~<br>~~Oo~~<br>~~LLLLLe~~|||||||
|Gm<br>~~LL~~|Trans-Conductance<br>~~LL~~|—<br>~~LL~~|—<br>~~LL~~|27<br>~~LL~~<br>~~LL~~<br>~~LL~~|—<br>~~LL~~<br>~~LL~~<br>~~LL~~|µA/V<br>~~LL~~<br>~~Le~~<br>~~LL~~|
|ISOURCE<br>~~Ln~~|Amplifier Source Current<br>~~Ln~~|—<br>~~Ln~~|—<br>~~Ln~~|7.2<br>~~LL ~~<br>~~Ln~~<br>~~LL~~|—<br> ~~LL ~~<br>~~Ln~~<br>~~LL~~|µA<br> ~~Le~~<br>~~Ln~~<br>~~LL~~|
|**Feedback Input Section**<br>~~LL LL~~<br>~~LL~~|||||||
|VFB_CV<br>~~TL~~|FB CV Threshold<br>~~TL~~|—<br>~~TL~~|2.86<br>~~TL~~|3.0<br>~~TL~~<br>~~LL~~|3.26<br>~~TL~~<br>~~LL~~|V<br>~~TL~~<br>~~LL~~|
|**ADIM Section**<br>~~LL~~<br>~~LLLLLe~~<br>~~a~~|||||||
|—<br>~~LL~~<br>~~a~~|Analog Dimming Range on ADIM<br>~~LL~~<br>|—<br>~~LL~~|0.05<br>~~LL~~|—<br>~~LL~~<br>~~LL~~|2.5<br>~~LL~~<br>~~LL~~|V<br>~~LL~~<br>~~Le~~|
|—<br>~~a ~~<br>~~Se~~|Analog Dimming High Level<br> ~~**a**~~|—<br>~~**OO**~~|2.45<br>~~**OO**~~|2.5<br>~~LL ~~<br>~~**OO**~~|2.55<br> ~~LL ~~|V<br> ~~Le~~|
|—<br> <br>~~Se~~|Analog Dimming Range Ratio<br> ~~**a**~~|—<br>~~**OO**~~|5%<br>~~**OO**~~|—<br>~~**OO**~~|100%|—|
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AL1665 Document number: DS41772 Rev. 3 - 2
March 2020 © Diodes Incorporated
**AL1665**
**Electrical Characteristics** (@TA = +25°C, unless otherwise specified.) (continued)
|**Symbol**<br>~~SO~~|**Parameter**<br>~~SO~~|**Conditions**<br>~~SO~~|**Min**<br>~~SO~~|**Typ**<br>~~SO~~|**Max**<br>~~SO~~|**Unit**<br>~~SO~~|
|---|---|---|---|---|---|---|
|**NTC/PWM Section**<br>~~TT~~<br>~~LILZLD~~<br>~~ee~~|||||||
|VNTC/PWM(PULL-UP)<br>~~SL~~<br>~~ee~~<br>~~Se~~|Pullup Voltage when NTC/PWM Open<br>~~SL~~<br><br>|NTC/PWM Pin Open<br>~~SL~~<br>|—<br>~~SL~~<br><br>~~I~~|2.5<br>~~SL~~<br>~~LI~~<br><br>~~es~~|—<br>~~SL~~<br>~~LZ~~<br>|V<br>~~SL~~<br>~~LD~~<br>|
|IOTP(REF)<br>~~ee~~<br>~~Se~~|Reference Current for Direct Connection of<br>NTC/PWM(Note 9)<br>~~ns~~<br>|—<br>~~ns~~|70.5<br>~~ns~~<br>~~I~~|85<br>~~LI~~<br>~~ns~~<br>~~es~~|91<br>~~LZ~~<br>~~ns~~|µA<br>~~LD~~<br>~~ns~~|
|VOTP(OFF)<br>~~ee~~<br>~~Se~~<br>~~ee~~<br>~~ee~~|Fault Detection Level for OTP (Note 8)<br><br>~~a~~<br><br>|VNTC/PWMFalling<br><br>|—<br><br>~~I~~<br><br>~~I~~|0.50<br>~~LI ~~<br><br>~~es~~<br><br>~~es~~|—<br> ~~LZ ~~<br><br>|V<br> ~~LD~~<br><br>|
|VOTP(ON)<br>~~Se ~~<br>~~ee~~<br>~~ee~~<br>~~ee~~|NTC/PWM Pin Level for Operation Recovery<br>afteranOTP Detection<br> ~~a~~<br>~~ns~~<br>~~ee~~|VNTC/PWMRising<br>~~ns~~<br>~~rs~~|—<br>~~I~~<br>~~ns~~<br>~~I~~<br>~~Gs~~|0.70<br>~~es~~<br>~~ns~~<br>~~es~~<br>~~es~~|—<br>~~ns~~<br>~~es~~|V<br>~~ns~~|
|tOTP(START)<br> <br>~~ee~~<br>~~ee~~<br>~~ee~~<br>~~es~~|OTP Blanking Time when Circuit Starts<br>Operating (Note 9)<br> ~~a~~<br><br>~~ee~~<br>~~ee~~<br>|—<br><br>~~rs~~<br>~~ee~~<br>|250<br><br>~~I~~<br>~~Gs~~<br>~~Ge~~<br>|—<br><br>~~es~~<br>~~es~~<br>~~Gs~~<br>|370<br><br>~~es~~<br>~~es~~<br>|µs<br><br>|
|VTF(START)<br>~~ee ~~<br>~~ee~~<br>~~es~~|NTC/PWM Pin Voltage at which Thermal<br>Foldback Starts(VREF is Decreased)<br> ~~ee~~<br>~~ee~~<br>|—<br>~~rs~~<br>~~ee~~<br>|0.94<br>~~I~~<br>~~Gs~~<br>~~Ge~~<br>|1.00<br>~~es~~<br>~~es~~<br>~~Gs~~<br>|1.06<br>~~es~~<br>~~es~~<br>|V<br>|
|VTF(STOP)<br> <br>~~ee~~<br>~~es~~|NTC/PWM Pin Voltage at which Thermal<br>Foldback Stops(VREF is Clamped to VREF50)<br> ~~ee~~<br>~~ee~~<br>~~rs~~|—<br>~~rs~~<br>~~ee~~<br>~~rs~~|0.64<br>~~Gs ~~<br>~~Ge~~<br>~~rs~~|0.69<br> ~~es ~~<br>~~Gs~~<br>~~rs~~|0.74<br> ~~es~~<br>~~es~~<br>~~rs~~|V<br>~~rs~~|
|VREF(50)<br>~~es~~<br>~~a~~|VREF @ VNTC/PWM = 600mV (Percent of VREF)<br>~~ee~~<br><br>~~a~~<br>~~a~~|—<br>~~ee ~~<br><br>~~a~~<br>~~a~~|40<br> ~~Ge ~~<br><br>~~a~~<br>~~a~~|50<br> ~~Gs ~~<br><br>~~a~~<br>~~a~~|60<br> ~~es~~<br><br>~~a~~<br>~~a~~|%<br><br>~~a~~<br>~~a~~|
|**Thermal Foldback Section**<br>~~|~~|||||||
|TREG<br>~~|~~<br>~~ee~~|Overheating Temperature Regulation (Note 7) —<br>~~|~~|Overheating Temperature Regulation (Note 7) —<br>~~|~~|—<br>~~|~~|+150<br>~~|~~|—<br>~~|~~|°C<br>~~|~~|
|**Overtemperature Protection Section**<br>~~ee~~|||||||
|—<br>~~ee~~|Shutdown Temperature (Notes 7, 8)|—|—|+180|—|°C|
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AL1665 Document number: DS41772 Rev. 3 - 2
March 2020 © Diodes Incorporated
**AL1665**
## **Performance Characteristics** (Note 10)
## **Startup Threshold Voltage vs. Ambient Minimum Operating Voltage vs. Ambient Temperature Temperature**
**==> picture [489 x 585] intentionally omitted <==**
**----- Start of picture text -----**<br>
19.0 8.0<br>7.8<br>18.5 P| | | yt] 4 7.6 ee<br>7.4<br>18.0 COOOL CeT) = SESS<br>7.2<br>17.5 Bane 7Zane 7.0 P|ee | er<br>6.8<br>17.0 Pieri4 il i 6.6 pope}aett tt<br>6.4<br>16.5 ec eee<br>6.2<br>16.0 PTT tt ttt i 6.0 PeFEESet<br>-40 -20 0 20 40 60 80 100 120 -40 -20 0 20 40 60 80 100 120<br>Ambient Temperature (oC) Ambient Temperature (oC)<br> VCC OVP Voltage vs. Ambient Temperature Startup Current vs. Ambient Temperature<br>30 250<br>29 230<br>28 H++4+4+-4+4+4+4 0° 210 Eee eet<br>27 Po 190 P| | [| | | | | ft<br>26 Po) ee 170 Po ee<br>25 Po) lees 150 eee<br>24 130<br>Peet a<br>23 Re Tr 110 Pee oE<br>22 90<br>21 t+4+$++4+4+4— 70 SR<br>20 | | | | [ | | [ | 50 | | | [| | | | | if<br>-40 -20 0 20 40 60 80 100 120 -40 -20 0 20 40 60 80 100 120<br>Ambient Temperature (oC) Ambient Temperature (oC)<br> Operating Current vs. Ambient Temperature CS Reference Voltage vs. Ambient Temperature<br>1.00 0.410<br>0.95 ne a<br>0.405<br>0.90<br>0.400<br>0.85<br>ee I<br>0.80 0.395<br>a |<br>0.75<br>pt etT tt tt i 0.390 hE]<br>0.70<br>eft} tt 0.385 Fe[I<br>0.65 mT<br>0.60 TPPEererererey 0.380 LEE_LELL_L!]TI<br>-40 -20 0 20 40 60 80 100 120 -40 -20 0 20 40 60 80 100 120<br>Ambient Temperature (oC) Ambient Temperature (oC)<br>(mA)<br>ICC_OPR<br>(V)<br>CC_TH<br>V<br> (V)<br>CC_OVP<br>V<br>(V)<br>CS_REF<br>V<br>A)<br>(ICC_st<br> (V)<br>OPR_MIN<br>V<br>**----- End of picture text -----**<br>
Note: 10. These electrical characteristics are tested under DC condition. The ambient temperature is equal to the junction temperature of the device.
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**AL1665**
## **Performance Characteristics** (continued)
**==> picture [231 x 195] intentionally omitted <==**
**----- Start of picture text -----**<br>
CS Clamp Reference Voltage vs. Ambient<br>Temperature<br>2.20<br>2.15<br>P| t | tf tf ft ft<br>2.10<br>P| | ft tf | ft ft<br>2.05<br>pf tt ft | |<br>2.00<br>1.95 =FPETPE LE]<br>1.90 el<br>1.85 TT ooo<br>1.80 | | | | | | [ | |<br>-40 -20 0 20 40 60 80 100 120<br>Ambient Temperature (oC)<br>(V)<br>CS_CLAMP<br>V<br>**----- End of picture text -----**<br>
## **FB CV Threshold vs. Ambient Temperature**
**==> picture [227 x 173] intentionally omitted <==**
**----- Start of picture text -----**<br>
3.3<br>3.2 | | | | | | | fd<br>3.1 rT oT | fl dt<br>3.0 elltd<br>2.9<br>SS<br>2.8<br>fF [| | ft tt<br>2.7 P| | ft tt [tt] ttt<br>2.6 | | | | | | ft<br>-40 -20 0 20 40 60 80 100 120<br>Ambient Temperature (oC)<br>(V)<br>FB_CV<br>V<br>**----- End of picture text -----**<br>
## **FB CV Threshold vs. VCC Voltage**
## **CS Reference Voltage vs. VCC Voltage**
**==> picture [482 x 374] intentionally omitted <==**
**----- Start of picture text -----**<br>
3.6 0.410<br>3.4 PEt tT EE te 0.405 PET<br>3.2 aaa 0.400 PTTee Ey<br>3.0 0.395<br>ERR | tt ee<br>2.8 TT EEL LT 0.390 eeene<br>2.6 PEE ee LLL 0.385 PPT<br>2.4 Pitt tt tee 0.380 FT Tee| tteeeee<br>7 9 11 13 15 17 19 21 23 7 9 11 13 15 17 19 21 23<br>VCC Voltage (V) VCC Voltage (V)<br> PWM Dimming Curve Analog Dimming Curve<br>100 100<br>90 90<br>80 SSEEE ee 80 Gece__<br>70 Oe 70<br>60 a 60 PEPE EEE<br>50 Os 50 FTEERATERAT<br>40 a 40 FCECE RACE RACE<br>30 Os 30 ACEC EEE<br>20 Os a 20 CEPa4EEEEEEa4EEEEEE4EEEEEEEEEEEEEEE<br>10 PWM Frequency=1kHz 10<br>0 SzZI _ 0 FACEAAT EELLELEEEEAAT EELLELEEEE EELLELEEEEEEE LLLE<br>0 10 20 30 40 50 60 70 80 90 100 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4<br>PWM Duty (%) VADIM (V) (V)<br>(V)<br>FB_CV<br> V<br>Dimming percentage (%) Dimming Percentage (%)<br> (V)<br>CS_REF<br>V<br>**----- End of picture text -----**<br>
**==> picture [230 x 172] intentionally omitted <==**
**----- Start of picture text -----**<br>
100<br>90<br>80 Gece__<br>70 oo<br>60 PEPE EEE<br>50 FTEERATERAT<br>40 FCECE RACE RACE<br>30 ACEC EEE<br>20 CEPa4EEEEEEa4EEEEEE4EEEEEEEEEEEEEEE<br>10<br>0 FACEAAT EELLELEEEEAAT EELLELEEEE EELLELEEEEEEE LLLE L<br>0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6<br>VADIM (V)<br>Dimming Percentage (%)<br>**----- End of picture text -----**<br>
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AL1665 Document number: DS41772 Rev. 3 - 2
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© Diodes Incorporated
**AL1665**
## **Application Information**
The AL1665 is a constant-current high-PF flyback and buck-boost controller with primary side regulation (PSR), targeting LED lighting applications. The device eliminates the optocouplers or the secondary feedback circuits, which is helpful to minimize the cost of the whole system. High power factor is achieved by constant on-time operation. In order to reduce the switching losses and improve EMI performance, quasi-resonant switching mode is applied. The AL1665 integrates multiple protections including UVLO protection, VCC overvoltage protection, output open-voltage protection, overcurrent protection, thermal foldback protection, and overtemperature protection. The AL1665 can support analog and PWM dimming modes.
**==> picture [381 x 350] intentionally omitted <==**
**----- Start of picture text -----**<br>
C7 R14<br>L1 T1<br>R10 C5 D3 R11 + C6 OUT<br>C1 C2 RTH<br>F 1<br>D2<br>AC VR 1<br>Input h i Aux R4 D1<br>DB1<br>CVCC<br>mr R5 VCC ADIM D4<br>FB AL1665 OUT ta Q1<br>R6 COMPNTC/ R9<br>RCOMP PWM GND CS<br>U1<br>CCOMP RCS<br>or 1] aie<br>Figure 1. Flyback Application Circuit<br>L1<br>T1<br>C1 C2 RTH R11 C6 OUT<br>F 1<br>D3<br>AC VR 1<br>Input eo Aux R4 D1<br>hi oT DB1 pts<br>mr R5 CVCC VCC ADIM D4<br>Q1<br>FB OUT<br>R6 COMPNTC/AL1665 R9<br>RCOMP PWM GND CS<br>CCOMP RCS<br>+<br>**----- End of picture text -----**<br>
Figure 2. Buck-Boost Application Circuit
## **Start Up**
After AC supply is powered on, the capacitor CVCC across VCC and GND pin charges up by BUS voltage through a start-up resistor RTH. Once VCC reaches VCC_TH, the internal blocks start to work. VCC is supplied by VBUS until the auxiliary winding of flyback transformer could supply enough energy to maintain VCC above VOPR_MIN. If VCC voltage is lower than VOPR_MIN, the switch turns off.
After VCC exceeds VCC_TH, the drive blocks do not start to switch on/off signals until VCOMP is higher than the initial voltage VCOMP_ST, which can be programmed by RCOMP. The formula is shown below. Such design can program startup on time to reduce the startup time or the output overshoot current.
**==> picture [152 x 12] intentionally omitted <==**
Where VCOMP_ST is the pre-charged voltage of COMP pin. Figure 1 shows RCOMP.
Generally, a big capacitance of CCOMP is necessary to achieve high power factor and stabilize the system loop (1μF to 2μF is recommended). The pre-charged voltage in start-up procedure can be programmed by RCOMP.
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AL1665 Document number: DS41772 Rev. 3 - 2
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© Diodes Incorporated
**AL1665**
## **Application Information** (continued)
## **Protections**
## **1. Output Open Protection (OVP)**
The output voltage is reflected by the voltage on transformer’s auxiliary winding. Both the FB pin and the VCC pin of IC have the overvoltage protection function. When there is a rapid line and load transient, the output voltage can exceed the regulated value. If VCC exceeds VCC_OVP, the VCC overvoltage protection triggers, the switch turns off, and the VCC discharges. Once VCC is lower than VOPR_MIN, the IC shuts down and powers on again by BUS voltage through the start-up resistor. If VFB exceeds VFB_CV, the FB overvoltage protection triggers, the switch turns off, and VCC latches for 16s then VCC discharges. Once VCC is below VOPR_MIN, the IC shuts down and powers on again by BUS voltage through the start-up resistor. Power dissipation is low when FB overvoltage protection occurs.
Thus, output overvoltage depends on the minimum voltage between both OVP protections’ limitation, which can be found with the below formula.
**==> picture [208 x 27] intentionally omitted <==**
Where:
- VOVP is the output overvoltage setting
- R5 and R6 shown in Figure 1 are divider resistors connected from the auxiliary winding
- NAUX is the turns of auxiliary wind
- NS is turns of the secondary wind
- VCC_OVP is the OVP voltage of VCC
## **2. Output Short Protection (OSP)**
When the output is shorted, the output voltage is clamped to zero. The output voltage of the auxiliary winding, which is proportional to the output winding, will drop down too. If VFB drops below 0.4V, the output short protection will be triggered, the device cannot detect the tOFF time, and the device controls the system operation at 4kHz low frequency.
## **3. Overcurrent Protection (OCP)**
The AL1665 has a built-in cycle-by-cycle overcurrent protection of primary inductor current. When the CS pin voltage reaches the voltage VCS_CLAMP, the switch turns off until the next switch period. The maximum peak current (IPEAK (MAX)) of the inductor can be calculated as follows:
**==> picture [98 x 26] intentionally omitted <==**
Where:
- VCS_CLAMP means primary current clamp voltage, which is 2V.
- RCS is current sense resister, which is shown as Figure 1
## **4. CS Short Protection**
When the CS pin shorts to GND, CS voltage latches to zero. If CS is detected lower than 0.3V for seven pulses, the CS short protection triggers, the switch turns off, and VCC latches for 16s then VCC discharges. Once VCC is below VOPR_MIN, the IC shuts down and powers on again by the BUS voltage through the startup resistor. High rush current appears when CS is shorted to GND, and it may damage the components.
## **5. Secondary Diodes/Primary Windings/Secondary Windings Short Protection**
The CS voltage is high when secondary diodes/primary windings/secondary windings short. If the CS voltage is higher than VCS_OCP, the protection triggers, the switch turns off, and VCC latches for 16s then VCC discharges. Once VCC is below VOPR_MIN, the IC shuts down and powers on again by the BUS voltage through the startup resistor. Power dissipation is low when output short protection occurs.
## **6. Thermal Foldback Protection (TFP)**
Connect a NTC between the NTC/PWM pin and ground to detect an overtemperature condition. In response to a high temperature (detected if VNTC/PWM drops below VTF(START)), the circuit gradually reduces the LED current down 50% of its nominal value when VNTC/PWM reaches VTF(STOP), in accordance with the characteristic of Figure 3. If this thermal foldback cannot prevent the temperature from rising (testified by VNTC/PWM dropping below VOTP), the circuit latches off or enters the auto-recovery mode and cannot be reoperated until VNTC/PWM exceeds VOTP(ON) to provide some temperature hysteresis (around +10°C typically).
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AL1665 Document number: DS41772 Rev. 3 - 2
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© Diodes Incorporated
**AL1665**
## **Application Information** (continued)
The OTP thresholds nearly correspond to the following resistances of the NTC:
- Thermal foldback starts when RNTC <=RTF(START)(11.7kΩ typically)
- Thermal foldback stops when RNTC <=RTF(STOP) (8.0kΩ typically)
- OTP triggers when RNTC <= ROTP(OFF) (5.9kΩ typically)
- OTP is removed when RNTC >= ROTP(ON) (8.0kΩ typically)
At startup, when VCC reaches VCC(ON), the OTP comparator blanks for at least 250µs in order to allow the NTC/PWM pin voltage to reach its nominal value if a filtering capacitor is connected to the NTC/PWM pin. This would avoid flickering of the LED light during turn-on.
**==> picture [221 x 155] intentionally omitted <==**
**----- Start of picture text -----**<br>
IOUT Temperature Increases<br>Temperature Decreases<br>IOUT(NOM) Fe<br>50%IOUT(NOM)<br>VOTP(OFF) VTF(STOP) VTF(START) VNTC/PWM<br>VOTP(ON)<br>Shutdown<br>**----- End of picture text -----**<br>
Figure 3. Output Current Reduction vs NTC/PWM Pin Voltage
## **7. Overtemperature Protection (OTP)**
The AL1665 has built-in overtemperature protection (OTP) function. When the temperature goes up to +180°C, the overtemperature protection is triggered, which leads to VCC UVLO. When OTP recovers, the system can be restarted.
## **Output Constant Current Control**
According to the definition of mean output current, the mean output current can be obtained as following:
**==> picture [137 x 30] intentionally omitted <==**
Where:
- IO_MEAN is the mean output current
- ISP is the secondary peak current of transformer
- tONS is the discharge time of secondary side of transformer
- tSW is the switch period
According to the principle of AL1665 closed-loop control, the voltage of RCS is sampled when the switch turns off, and the value is held until the discharge time tONS is over. It can be described by following formula:
**==> picture [108 x 37] intentionally omitted <==**
Where:
- IP is the primary peak current of transformer
- RCS is the current sense resister, which is shown in Figure 1
- tONS is the discharge time of secondary side of transformer
- tSW is the switch period
- VREF is internal reference voltage that is equal to 0.4V
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AL1665 Document number: DS41772 Rev. 3 - 2
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**AL1665**
## **Application Information** (continued)
The peak current at secondary side has the following relationship with primary side peak current if the effect of the leakage inductor is neglected.
**==> picture [61 x 14] intentionally omitted <==**
Where NPS is the turns’ ratio of flyback transformer (NPS=1 for buck-boost), and IP is the primary peak current of the transformer.
According to these above formulas, the mean output current can be induced finally by the following equation:
**==> picture [94 x 29] intentionally omitted <==**
Where:
- IO_MEAN is the mean output current
- RCS is the current sense resister, which is shown as Figure 1 and Figure 2
- VREF is the internal reference voltage that is equal to 0.4V
- NPS is the turns’ ratio of flyback transformer (NPS = 1 for buck-boost)
Therefore, the constant output current control can be realized with appropriate parameter design.
## **PF and THD Compensation Circuit**
In typical application, AL1665 can provide PF>0.9 and THD <40%. It can improve PF>0.95 and THD<20% by adding the compensation circuit as below. The VBUS is connected to bus line, which is after the rectifier bridge. The COMP pin voltage increases an offset that is almost followed with bus line voltage in the circuit. Due to the COMP voltage controls, the switch-on time, the phase difference between input voltage and input current, is reduced, which can optimize the PF and THD. In the circuit, the range of resister value R12 is from 800kΩ to 1.5MΩ, and the range of resistor value R13 is from 500Ω to 5.1kΩ. The range of capacitance C11 is 1µF to 2µF. The PF and THD circuit can be improved by fine-tuning these components.
**==> picture [383 x 209] intentionally omitted <==**
The AL1665 can achieve good line regulation by adjusting the FB pull-up resistor RFB1 and the CS external horizontal resistor RCS1. RFB2 is the FB pull-down resistor. Figure 5 shows this circuit. As RFB2 is far larger than RFB3, during tONP, the VFB can be calculated approximately as:
Where:
- K is conversion coefficient of IFB3 that is equal to 0.013*10[-3]
- VIN_RMS is the input RMS voltage
- NAP is the turns’ ratio of auxiliary winding and primary winding
- RFB3 is the internal FB pulldown resistor that is connected to the system during tONP time and equals to 184Ω
- RCS2 is the internal horizontal resistor that is 6kΩ
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AL1665 Document number: DS41772 Rev. 3 - 2
March 2020 © Diodes Incorporated
**AL1665**
## **Application Information** (continued)
The output current can be calculated as:
Where:
**==> picture [425 x 227] intentionally omitted <==**
**----- Start of picture text -----**<br>
IO_MEAN= [N] ∙ [PS] ∙(VREF-VCS_OFFSET)= [N] ∙ [PS] ∙ VREF- K ∙ √2 ∙ VIN _RMS ∙ NAP ∙ RFB3 ∙ (RCS1+RCS2)<br>2 RCS 2 RCS [ RFB1+RFB3 ]<br> is the internal reference voltage that is equal to 0.4V<br>Q1 AL1665 FB RFB1<br>VREF K tONP<br>CS IFB3<br>V→I RFB2<br>RCS1 RCS2 RFB3<br>RCS<br>H eit<br>Figure 5. Line Regulation Compensation Circuit<br>**----- End of picture text -----**<br>
VREF is the internal reference voltage that is equal to 0.4V
## **Dimming Mode**
The AL1665 can support two dimming modes: analog dimming and PWM dimming.
## **1. Analog Dimming Mode**
In analog dimming mode, the dimming signal is added to ADIM pin directly to realize dimming function. Figure 6 shows the setting circuit. When VAPWM is higher than 2.5V, the driver outputs 100% of rated current, and when the voltage VADIM is within the 50mV to 2.5V range, the output current changes linearly with the voltage VAPWM. Figure 7 shows the dimming curve, and the dimming range is from 5% to 100%.
**==> picture [175 x 85] intentionally omitted <==**
**----- Start of picture text -----**<br>
50mv~2.5V<br>Dimming Signal<br>ADIM<br>°<br>AL1665<br>C<br>APWM<br>**----- End of picture text -----**<br>
**==> picture [172 x 121] intentionally omitted <==**
**----- Start of picture text -----**<br>
100%<br>5%<br>0 50mV 2.5V<br>**----- End of picture text -----**<br>
Figure 6. Analog Dimming Setting Circuit
Figure 7. Analog Dimming Curve
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AL1665 Document number: DS41772 Rev. 3 - 2
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**AL1665**
## **Application Information** (continued)
## **2. PWM Dimming Mode**
In PWM dimming mode, the dimming signal is added to NTC/PWM pin. Figure 8 shows the setting circuit. The output current is chopped by the dimming signal directly. The logic high level of the dimming signal must be higher than 1V while the logic low level is lower than 0.5V. The switch turns off at logic low level. Figure 9 shows the dimming curve. The dimming range can be 100% to 0.5% with 1KHz frequency of PWM signal.
**==> picture [165 x 74] intentionally omitted <==**
**----- Start of picture text -----**<br>
PWM Dimming Signal<br>NTC<br>/PWM<br>AL1665<br>**----- End of picture text -----**<br>
**==> picture [227 x 170] intentionally omitted <==**
**----- Start of picture text -----**<br>
100<br>80<br>60<br>40<br>20<br>PWM Frequency=1kHz<br>0<br>0 20 40 60 80 100<br>PWM Duty (%)<br>Output Current Percentage (%)<br>**----- End of picture text -----**<br>
Figure 8. PWM Dimming Setting Circuit
Figure 9. PWM Dimming Curve
## **Operation Parameters Design**
## **1. Setting the Current Sense Resistor RCS**
The current sense resistance is calculated using the following equation:
**==> picture [79 x 31] intentionally omitted <==**
Where:
- IO_MEAN is the mean output current
- RCS is the current sense resister, which is shown as Figure 1
- VREF is the internal reference voltage that is equal to 0.4V
- NPS is the turns’ ratio of flyback transformer (NPS=1 for buck-boost)
## **2. Setting Transformer Selection (T1)**
NPS is limited by the electrical stress of the switch MOSFET and can be calculated with the following formula:
**==> picture [209 x 34] intentionally omitted <==**
Where:
- VMOS_(BR)DS is the breakdown voltage of the switch MOSFET
- VIN_MAX is the max rated input voltage
- ∆VS is the overshoot voltage clamped by RCD snobbier during OFF time
- VO is the output voltage
- VD_F is the forward voltage of secondary diode
- NPS is the turns’ ratio of flyback transformer (NPS=1 for buck-boost)
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**AL1665**
## **Application Information** (continued)
For boundary conduction mode and constant on-time method, the peak current of primary inductance can be calculated as:
**==> picture [181 x 39] intentionally omitted <==**
Where
- VIN_RMS is the rate input voltage
- IP is the primary inductance current
- NPS is the turns’ ratio of flyback transformer (NPS=1 for buck-boost)
- IO_MEAN is the mean output current
- VO is the output voltage
The switching frequency is not constant for AL1665 due to boundary conduction mode. To set the minimum switching frequency fMIN at the crest of the minimum AC input, primary inductance can be obtained by the following formula:
**==> picture [137 x 28] intentionally omitted <==**
Where
- VIN_RMS is the rate input voltage
- IP is the primary inductance current
- NPS is the turns’ ratio of flyback transformer (NPS=1 for buck-boost)
- VO is the output voltage
- fMIN is the minimum switching frequency at the crest of the minimum AC input
According to the Faraday’s Law, the winding number of the inductance can be calculated by:
**==> picture [50 x 65] intentionally omitted <==**
Where:
- Ae is the core effective area
- Bm is the maximum magnetic flux density
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**AL1665**
## **Ordering Information**
||||**AL1665 X- X**|**AL1665 X- X**||||||
|---|---|---|---|---|---|---|---|---|---|
|Packing<br>Package<br>Product Name<br>~~So~~||||||||||
||||S : SO-8 (Standard)|S : SO-8 (Standard)|13 : 13" Tape & Reel|13 : 13" Tape & Reel||||
|||||||**13” Tape and Reel**||**13” Tape and Reel**||
|**Part Number**|**Package Code**||**Package**|||||||
||||||**Quantity**||||**Part Number Suffix**|
|AL1665S-13||S|SO-8 (Standard)|4000/Tape & Reel||4000/Tape & Reel|||-13|
## **Marking Information**
## **(Top View)**
**==> picture [344 x 108] intentionally omitted <==**
**----- Start of picture text -----**<br>
8 7 6 5<br>[}| [i ft ff<br>Logo<br>YY : Year : 19, 20, 21~<br>Marking ID AL1665 WW : Week : 01~52; 52<br>represents 52 and 53 week<br>YY WW X X<br>X X : Internal Code<br>1 2 3 4<br>**----- End of picture text -----**<br>
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**AL1665**
## **Package Outline Dimensions** (All dimensions in mm.)
Please see http://www.diodes.com/package-outlines.html for the latest version.
## **SO-8 (Standard)**
**==> picture [502 x 227] intentionally omitted <==**
**----- Start of picture text -----**<br>
E1<br>h<br>A3<br>c<br>E A2 A SO-8 (Standard)<br>Ø GS eating Planeauge Plane Dim Min Max Typ<br>1 L A -- 1.75 --<br>e A1 A1 0.10 0.25 --<br>D saae l ==== A2 1.25 1.65 --<br>A3 0.50 0.70 --<br>b<br>b 0.30 0.51 --<br>c 0.15 0.25 --<br>D 4.80 5.00 --<br>E 5.80 6.20 6.00<br>E1 3.80 4.00 --<br>e -- -- 1.27<br>h 0.25 0.50 --<br>L 0.45 0.82 --<br>Ø 0° 8° --<br>All Dimensions in mm<br> OPTION A OPTION B<br>(TOP VIEW) (TOP VIEW)<br>45°<br>**----- End of picture text -----**<br>
## **Suggested Pad Layout**
Please see http://www.diodes.com/package-outlines.html for the latest version.
## **SO-8 (Standard)**
**==> picture [334 x 140] intentionally omitted <==**
**----- Start of picture text -----**<br>
X1<br>Dimensions Value (in mm)<br>poogd C 1.27<br>Y1 X 0.802<br>X1 4.612<br>Y 1.505<br>Y1 6.50<br>Y<br>ager C X ==<br>**----- End of picture text -----**<br>
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**AL1665**
## **IMPORTANT NOTICE**
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This document is written in English but may be translated into multiple languages for reference. Only the English version of this document is the final and determinative format released by Diodes Incorporated.
## **LIFE SUPPORT**
Diodes Incorporated products are specifically not authorized for use as critical components in life support devices or systems without the express written approval of the Chief Executive Officer of Diodes Incorporated. As used herein: A. Life support devices or systems are devices or systems which:
1. are intended to implant into the body, or
2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in significant injury to the user.
B. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or to affect its safety or effectiveness.
Customers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support devices or systems, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products and any use of Diodes Incorporated products in such safety-critical, life support devices or systems, notwithstanding any devices- or systems-related information or support that may be provided by Diodes Incorporated. Further, Customers must fully indemnify Diodes Incorporated and its representatives against any damages arising out of the use of Diodes Incorporated products in such safety-critical, life support devices or systems. Copyright © 2020, Diodes Incorporated
**www.diodes.com**
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AL1665 Document number: DS41772 Rev. 3 - 2
March 2020 © Diodes Incorporated
Updated at April 29, 2026
About Novapart
Novapart is a B2B electronic component broker specialising in stock shortages and cost reduction. We source hard-to-find parts and identify compliant alternatives across a catalogue of 420,000+ components from 500+ manufacturers.
Learn more →Stock Shortage Specialist
When a component is unavailable, discontinued or has an unacceptable lead time, we tap into our network of vetted European and Asian distributors to source what you need — without compromising on quality or traceability.
Request a quote →Compliant Alternatives
We identify pin-to-pin, electrically equivalent substitutes that meet the same certifications (RoHS, AEC-Q100, REACH) as your original specification — validated against datasheets, not just part numbers. Often at a lower cost.
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