SZMMSZ5242ET1G

Zener Single Diode, 12 V, 500 mW, SOD-123, 2 Pins, 150 °C, Surface Mount

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Manufacturer: ONSEMI
Product type: Zener Single Diodes
Zener Voltage Vz Typ:12V; Power Dissipation Pd:500mW; Diode Case Style:SOD-123; Zener Tolerance ±:5%; No. of Pins:2Pins; Operating Temperature Max:150°C; Product Range:SZMMSZ52xx
SVHC: No SVHC (25-Jun-2025)
No. of Pins: 2Pins
Product Range: SZMMSZ52xxET1G
Qualification: AEC-Q101
Diode Mounting: Surface Mount
Diode Case Style: SOD-123
Power Dissipation: 500mW
Zener Voltage Nom: 12V
Operating Temperature Max: 150°C

Delivery and price
Units per pack	5000
Price	0.067 €
Current stock	10+
Lead time	30 days

Datasheet

## MMSZ52xxET1G Series, SZMMSZ52xxET1G Series 

## Zener Voltage Regulators **500 mW SOD−123 Surface Mount** 

Three complete series of Zener diodes are offered in the convenient, surface mount plastic SOD−123 package. These devices provide a convenient alternative to the leadless 34−package style. 

## **http://onsemi.com** 

## **Features** 

- 500 mW Rating on FR−4 or FR−5 Board 

- Wide Zener Reverse Voltage Range − 2.4 V to 110 V 

- Package Designed for Optimal Automated Board Assembly 

- Small Package Size for High Density Applications 

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SOD−123<br>CASE 425<br>STYLE 1<br>**----- End of picture text -----**<br>


- General Purpose, Medium Current 

- ESD Rating of Class 3 (> 16 kV) per Human Body Model 

- Peak Power − 225 W (8 x 20 s) 

- SZ Prefix for Automotive and Other Applications Requiring Unique Site and Control Change Requirements; AEC−Q101 Qualified and PPAP Capable 

**==> picture [104 x 17] intentionally omitted <==**

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1 2<br>Cathode Anode<br>**----- End of picture text -----**<br>


## **MARKING DIAGRAM** 

- Pb−Free Packages are Available* 

## **Mechanical Characteristics:** 

> **CASE:** Void-free, transfer-molded, thermosetting plastic case **FINISH:** Corrosion resistant finish, easily solderable 

## **MAXIMUM CASE TEMPERATURE FOR SOLDERING PURPOSES:** 

260  C for 10 Seconds 

**POLARITY:** Cathode indicated by polarity band **FLAMMABILITY RATING:** UL 94 V−0 

**==> picture [135 x 75] intentionally omitted <==**

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1 xxx M<br>xxx = Device Code (Refer to page 2)<br>M = Date Code<br>= Pb−Free Package<br>**----- End of picture text -----**<br>


(Note: Microdot may be in either location) 

## **MAXIMUM RATINGS** 

**Rating Symbol Max Units ORDERING INFORMATION** ~~eses~~ @ TPeak Power Dissipation @ 20 s (Note 1)L  25C Ppk 225 W **Device Package Shipping**[†] ~~—~~ MMSZ52xxET1G SOD−123 3,000 / Total Power Dissipation on FR−5 Board,(Note 3) @ TL = 75C PD 500 mW (Pb−Free) Tape & Reel Derated above 75C 6.7 mW/C SZMMSZ52xxET1G SOD−123 3,000 / Thermal Resistance, (Note 2) R JA C/W (Pb−Free) Tape & Reel Junction−to−Ambient 340 MMSZ52xxET3G SOD−123 10,000 / ~~oo ee~~ Thermal Resistance, (Note 2) R JL C/W ~~tt~~ (Pb−Free) Tape & Reel ~~dt~~ Junction−to−Lead 150 †For information on tape and reel specifications, Junction and Storage Temperature Range TJ, Tstg −55 to+150 C including part orientation and tape sizes, pleaserefer to our Tape and Reel Packaging Specifications ~~—]~~ Brochure, BRD8011/D. Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended **DEVICE MARKING INFORMATION** Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. See specific marking information in the device marking 

See specific marking information in the device marking column of the Electrical Characteristics table on page 2 of this data sheet. 

1. Nonrepetitive current pulse per Figure 11. 

2. Thermal Resistance measurement obtained via infrared Scan Method. 

3. FR−5 = 3.5 x 1.5 inches, using the minimum recommended footprint. 

- *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. 

Publication Order Number: **MMSZ5221ET1/D** 

**1** 

 Semiconductor Components Industries, LLC, 2012 **February, 2012 − Rev. 8** 

**MMSZ52xxET1G Series, SZMMSZ52xxET1G Series** 

## **ELECTRICAL CHARACTERISTICS** (TA = 25C unless 

otherwise noted, VF = 0.95 V Max. @ IF = 10 mA) 

|otherwise n|oted, VF= 0.95 V Max. @ IF= 10 mA)|
|---|---|
|**Symbol**|**Parameter**|
|VZ|Reverse Zener Voltage @ IZT|
|IZT|Reverse Current|
|ZZT|Maximum Zener Impedance @ IZT|
|IZK|Reverse Current|
|ZZK|Maximum Zener Impedance @ IZK|
|IR|Reverse Leakage Current @ VR|
|VR|Reverse Voltage|
|IF|Forward Current|
|VF|Forward Voltage @ IF|



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I<br>IF<br>VZ VR<br>V<br>IR VF<br>IZT<br>Zener Voltage Regulator<br>**----- End of picture text -----**<br>


## **ELECTRICAL CHARACTERISTICS** (TA = 25C unless otherwise noted, VF = 0.9 V Max. @ IF = 10 mA) 

|**Device***|**Device**<br>**Marking**|**Zener Voltage**|**Zener Voltage**|(Notes 4 and 5)|(Notes 4 and 5)|**Zener Impedance**(Note 6)|**Zener Impedance**(Note 6)|**Zener Impedance**(Note 6)|**Leakage Current**|**Leakage Current**|
|---|---|---|---|---|---|---|---|---|---|---|
||||**VZ (V)**||**@ IZT**|**ZZT @ IZT**|**ZZK @ IZK**||**IR @ VR**||
|||**Min**|**Nom**|**Max**|**mA**|**�**|**�**|**mA**|**�A**|**V**|
|MMSZ5221ET1G<br>MMSZ5223ET1G<br>MMSZ5226ET1G<br>MMSZ5228ET1G<br>MMSZ5229ET1G|CA1<br>CA3<br>CA6<br>CA8<br>CA9|2.28<br>2.57<br>3.14<br>3.71<br>4.09|2.4<br>2.7<br>3.3<br>3.9<br>4.3|2.52<br>2.84<br>3.47<br>4.10<br>4.52|20<br>20<br>20<br>20<br>20|30<br>30<br>28<br>23<br>22|1200<br>1300<br>1600<br>1900<br>2000|0.25<br>0.25<br>0.25<br>0.25<br>0.25|100<br>75<br>25<br>10<br>5|1<br>1<br>1<br>1<br>1|
|MMSZ5231ET1G<br>MMSZ5232ET1G<br>MMSZ5234ET1G<br>MMSZ5235ET1G<br>MMSZ5236ET1G|CB2<br>CB3<br>CB5<br>CB6<br>CB7|4.85<br>5.32<br>5.89<br>6.46<br>7.13|5.1<br>5.6<br>6.2<br>6.8<br>7.5|5.36<br>5.88<br>6.51<br>7.14<br>7.88|20<br>20<br>20<br>20<br>20|17<br>11<br>7<br>5<br>6|1600<br>1600<br>1000<br>750<br>500|0.25<br>0.25<br>0.25<br>0.25<br>0.25|5<br>5<br>5<br>3<br>3|2<br>3<br>4<br>5<br>6|
|MMSZ5237ET1G<br>MMSZ5240ET1G<br>MMSZ5242ET1G<br>MMSZ5243ET1G<br>MMSZ5244ET1G|CB8<br>CC2<br>CC4<br>CC5<br>CC6|7.79<br>9.50<br>11.40<br>12.35<br>13.30|8.2<br>10<br>12<br>13<br>14|8.61<br>10.50<br>12.60<br>13.65<br>14.70|20<br>20<br>20<br>9.5<br>9.0|8<br>17<br>30<br>13<br>15|500<br>600<br>600<br>600<br>600|0.25<br>0.25<br>0.25<br>0.25<br>0.25|3<br>3<br>1<br>0.5<br>0.1|6.5<br>8<br>9.1<br>9.9<br>10|
|MMSZ5245ET1G<br>MMSZ5246ET1G<br>MMSZ5248ET1G<br>MMSZ5250ET1G<br>MMSZ5252ET1G|CC7<br>CC8<br>CD1<br>CD3<br>CD5|14.25<br>15.20<br>17.10<br>19.00<br>22.80|15<br>16<br>18<br>20<br>24|15.75<br>16.80<br>18.90<br>21.00<br>25.20|8.5<br>7.8<br>7.0<br>6.2<br>5.2|16<br>17<br>21<br>25<br>33|600<br>600<br>600<br>600<br>600|0.25<br>0.25<br>0.25<br>0.25<br>0.25|0.1<br>0.1<br>0.1<br>0.1<br>0.1|11<br>12<br>14<br>15<br>18|



4. The type numbers shown have a standard tolerance of 5% on the nominal Zener voltage. 

5. Nominal Zener voltage is measured with the device junction in thermal equilibrium at TL = 30C 1C. 

6. ZZT and ZZK are measured by dividing the AC voltage drop across the device by the ac current applied. The specified limits are for IZ(AC) = 0.1 IZ(dc) with the AC frequency = 1 kHz. 

- *Include SZ-prefix devices where applicable 

**http://onsemi.com** 

**2** 

## **MMSZ52xxET1G Series, SZMMSZ52xxET1G Series** 

**ELECTRICAL CHARACTERISTICS** (TA = 25C unless otherwise noted, VF = 0.9 V Max. @ IF = 10 mA) 

|**Device***|**Device**<br>**Marking**|**Zener Voltage**|**Zener Voltage**|(Notes 4 and 5)|(Notes 4 and 5)|**Zener Impedance**(Note 6)|**Zener Impedance**(Note 6)|**Zener Impedance**(Note 6)|**Leakage Current**|**Leakage Current**|
|---|---|---|---|---|---|---|---|---|---|---|
||||**VZ (V)**||**@ IZT**|**ZZT @ IZT**|**ZZK @ IZK**||**IR @ VR**||
|||**Min**|**Nom**|**Max**|**mA**|**�**|**�**|**mA**|**�A**|**V**|
|MMSZ5253ET1G<br>MMSZ5254ET1G<br>MMSZ5255ET1G<br>MMSZ5256ET1G<br>MMSZ5257ET1G|CD6<br>CD7<br>CD8<br>CD9<br>CE1|23.75<br>25.65<br>26.60<br>28.50<br>31.35|25<br>27<br>28<br>30<br>33|26.25<br>28.35<br>29.40<br>31.50<br>34.65|5.0<br>4.6<br>4.5<br>4.2<br>3.8|35<br>41<br>44<br>49<br>58|600<br>600<br>600<br>600<br>700|0.25<br>0.25<br>0.25<br>0.25<br>0.25|0.1<br>0.1<br>0.1<br>0.1<br>0.1|19<br>21<br>21<br>23<br>25|
|MMSZ5258ET1G<br>MMSZ5259ET1G<br>MMSZ5262ET1G<br>MMSZ5263ET1G|CE2<br>CE3<br>CE6<br>CE7|34.20<br>37.05<br>48.45<br>53.20|36<br>39<br>51<br>56|37.80<br>40.95<br>53.55<br>58.80|3.4<br>3.2<br>2.5<br>2.2|70<br>80<br>125<br>150|700<br>800<br>1100<br>1300|0.25<br>0.25<br>0.25<br>0.25|0.1<br>0.1<br>0.1<br>0.1|27<br>30<br>39<br>43|



4. The type numbers shown have a standard tolerance of 5% on the nominal Zener voltage. 

5. Nominal Zener voltage is measured with the device junction in thermal equilibrium at TL = 30C 1C. 

6. ZZT and ZZK are measured by dividing the AC voltage drop across the device by the ac current applied. The specified limits are for IZ(AC) = 0.1 IZ(dc) with the AC frequency = 1 kHz. 

*Include SZ-prefix devices where applicable 

**http://onsemi.com** 

**3** 

**MMSZ52xxET1G Series, SZMMSZ52xxET1G Series** 

## **TYPICAL CHARACTERISTICS** 

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8 100<br>7 TYPICAL TC VALUES TYPICAL TC VALUES<br>6 FOR MMSZ5221BT1G SERIES FOR MMSZ5221BT1G SERIES<br>5<br>4 V Z  @ I ZT V Z  @ I ZT<br>3<br>10<br>2<br>1<br>0<br>−1<br>−2<br>−3 1<br>2 3 4 5 6 7 8 9 10 11 12 10 100<br>VZ, NOMINAL ZENER VOLTAGE (V) VZ, NOMINAL ZENER VOLTAGE (V)<br>Figure 1. Temperature Coefficients Figure 2. Temperature Coefficients<br>(Temperature Range −55  C to +150  C) (Temperature Range −55  C to +150  C)<br>1.2 1000<br>RECTANGULAR<br>1.0 WAVEFORM, T A = 25C<br>0.8 PD versus TL 100<br>0.6<br>PD versus TA<br>0.4 10<br>0.2<br>0 1<br>0 25 50 75 100 125 150 0.1 1 10 100 1000<br>T, TEMPERATURE (C) PW, PULSE WIDTH (ms)<br>Figure 3. Steady State Power Derating Figure 4. Maximum Nonrepetitive Surge Power<br>1000 1000<br>TJ = 25C 75 V (MMSZ5267BT1)<br>IZ(AC) = 0.1 IZ(DC) 91 V (MMSZ5270BT1)<br>I Z = 1 mA f = 1 kHz<br>100 100<br>5 mA<br>20 mA<br>10 10<br>150C 75C 25C 0C<br>1 1<br>1 10 100 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2<br>VZ, NOMINAL ZENER VOLTAGE VF, FORWARD VOLTAGE (V)<br>C) C)<br> <br>, TEMPERATURE COEFFICIENT (mV/ , TEMPERATURE COEFFICIENT (mV/<br>VZ VZ<br>� �<br>, POWER DISSIPATION (WATTS) , PEAK SURGE POWER (WATTS)<br>D pk<br>P P<br>) �<br>, DYNAMIC IMPEDANCE ( , FORWARD CURRENT (mA)<br>ZZT IF<br>**----- End of picture text -----**<br>


**Figure 5. Effect of Zener Voltage on Zener Impedance** 

**Figure 6. Typical Forward Voltage** 

**http://onsemi.com** 

**4** 

**MMSZ52xxET1G Series, SZMMSZ52xxET1G Series** 

## **TYPICAL CHARACTERISTICS** 

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**----- Start of picture text -----**<br>
1000 1000<br>0 V BIAS TA = 25C 100<br>1 V BIAS<br>10<br>100<br>1<br>+150C<br>BIAS AT 0.1<br>50% OF V Z  NOM<br>0.01<br>10<br>+25C<br>0.001<br>−55C<br>0.0001<br>1 0.00001<br>1 10 100 0 10 20 30 40 50 60 70 80 90<br>VZ, NOMINAL ZENER VOLTAGE (V) VZ, NOMINAL ZENER VOLTAGE (V)<br>Figure 7. Typical Capacitance Figure 8. Typical Leakage Current<br>100 100<br>TA = 25C TA = 25C<br>10 10<br>1 1<br>0.1 0.1<br>0.01 0.01<br>0 2 4 6 8 10 12 10 30 50 70 90<br>VZ, ZENER VOLTAGE (V) VZ, ZENER VOLTAGE (V)<br>Figure 9. Zener Voltage versus Zener Current Figure 10. Zener Voltage versus Zener Current<br>(VZ Up to 12 V) (12 V to 91 V)<br>100<br>90 tr PEAK VALUE IRSM @ 8  � s<br>80 PULSE WIDTH (tP) IS DEFINED<br>AS THAT POINT WHERE THE<br>70 PEAK CURRENT DECAY = 8  � s<br>60<br>50 HALF VALUE IRSM/2 @ 20  � s<br>40<br>30<br>tP<br>20<br>10<br>0<br>0 20 40 60 80<br>t, TIME ( � s)<br>A)<br>�<br>, LEAKAGE CURRENT (<br>IR<br>C, CAPACITANCE (pF)<br>, ZENER CURRENT (mA) , ZENER CURRENT (mA)<br>IZ IZ<br>% OF PEAK PULSE CURRENT<br>**----- End of picture text -----**<br>


**Figure 11. 8**  **20 � s Pulse Waveform** 

**http://onsemi.com** 

**5** 

**MMSZ52xxET1G Series, SZMMSZ52xxET1G Series** 

## **PACKAGE DIMENSIONS** 

**SOD−123** CASE 425−04 ISSUE G 

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**----- Start of picture text -----**<br>
D<br>A NOTES:<br>1. DIMENSIONING AND TOLERANCING PER ANSI<br>A1 Y14.5M, 1982.<br>2. CONTROLLING DIMENSION: INCH.<br>1<br>MILLIMETERS INCHES<br>ÂÂÂÂ DIM MIN NOM MAX MIN NOM MAX<br>A 0.94 1.17 1.35 0.037 0.046 0.053<br>ÂÂÂÂ A1 0.00 0.05 0.10 0.000 0.002 0.004<br>b 0.51 0.61 0.71 0.020 0.024 0.028<br>HE E c --- --- 0.15 --- --- 0.006<br>D 1.40 1.60 1.80 0.055 0.063 0.071<br>E 2.54 2.69 2.84 0.100 0.106 0.112<br>HE 3.56 3.68 3.86 0.140 0.145 0.152<br>L 0.25 --- --- 0.010 --- ---<br>0  --- 10  0  --- 10 <br>2<br>of STYLE 1:<br>PIN 1. CATHODE<br>b L 2. ANODE<br>i ne C - _aeeee<br>SOLDERING FOOTPRINT*<br>0.91<br>ÉÉ 0.036 ÉÉ<br>ÉÉ ÉÉ 1.22<br>ÉÉ it ÉÉ 0.048<br>ÉÉ 2.36 ÉÉ<br>0.093<br>4.19<br>oS 0.165<br>SCALE 10:1 ; mm<br>inches<br>**----- End of picture text -----**<br>


*For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. 

**ON Semiconductor** and          are registered trademarks of Semiconductor Components Industries, LLC (SCILLC).  SCILLC reserves the right to make changes without further notice to any products herein.  SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time.  All operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts.  SCILLC does not convey any license under its patent rights nor the rights of others.  SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur.  Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part.  SCILLC is an Equal Opportunity/Affirmative Action Employer.  This literature is subject to all applicable copyright laws and is not for resale in any manner. 

## **PUBLICATION ORDERING INFORMATION** 

## **LITERATURE FULFILLMENT** : 

Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 80217 USA **Phone** : 303−675−2175 or 800−344−3860 Toll Free USA/Canada **Fax** : 303−675−2176 or 800−344−3867 Toll Free USA/Canada **Email** : orderlit@onsemi.com 

**N. American Technical Support** : 800−282−9855 Toll Free **ON Semiconductor Website** : **www.onsemi.com** USA/Canada 

**Europe, Middle East and Africa Technical Support: Order Literature** : http://www.onsemi.com/orderlit Phone: 421 33 790 2910 **Japan Customer Focus Center** For additional information, please contact your local Phone: 81−3−5817−1050 Sales Representative 

**http://onsemi.com** 

**MMSZ5221ET1/D** 

**6**

Updated at April 28, 2026

onsemi is a premier global supplier of intelligent power and sensing technologies, driving disruptive innovations across the automotive, industrial, and cloud infrastructure markets. Recognized for their commitment to sustainability and reliable supply chains, the company accelerates advancements in vehicle electrification, industrial automation, and 5G networks by solving the industry's most complex design challenges. At the core of their portfolio is an industry-leading selection of discrete semiconductors. This extensive range features thousands of high-performance bipolar transistors, single and dual MOSFETs, and a comprehensive array of diodes, including Zener, Schottky, and fast-recovery rectifiers. Engineered for superior thermal performance and energy efficiency, these foundational components are critical for demanding power conversion, switching, and signal conditioning applications. Beyond essential discretes, onsemi provides a robust suite of advanced power management and circuit protection solutions. Their lineup includes intelligent power modules, single IGBTs, and transient voltage suppression (TVS) diodes designed to safeguard sensitive circuitry. Complimented by integrated passive filters, AC/DC LED driver ICs, and specialized sub-2.4GHz RF transceivers, onsemi equips engineers with the scalable, high-quality technologies needed to build a cleaner, smarter, and more connected world.

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