AG102

V1.6 June 2014 Datasheet 

## _Silvertel_ 

## **Ag102** 

Intelligent Sealed Lead Acid Battery Charger Module 

## **Pb** 

## **1 Features** 

Multi-Stage Charging 

Battery Reversal Protection 

Reduced Power Consumption 

Wide DC or AC Input Voltage Range 

High Efficiency DC-DC Converter 

Intelligent ‘Top-up’ Float Charge Programmable Charge Current 

Battery Condition Indicator Output Temperature Compensation 

Overload & Short-circuit Protection 

Simple Integration 

## **2 Description** 

The Ag102 is a micro-processor based intelligent, cost effective, sealed lead acid (SLA) battery charging module. It uses digital technology to optimise the charging of standard, 12V sealed lead acid batteries between 1.2Ah and 7Ah capacity. Using various intelligent charging techniques the Ag102 technology will maximise the manufacturers specified battery lifetime. 

The Ag102 has a very wide input range of 9V to 36V DC. This gives extensive flexibility and means the system and charger requires just one, lower cost, power supply. When used in conjunction with Silvertel’s Power over Ethernet (PoE) module, the Ag102 can charge SLA batteries from power obtained over an Ethernet cable. 

© Silver Telecom 2014 

**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## _**Table of Contents**_ 

|1|Features ....................................................................................................................... 1|
|---|---|
|2|Description .................................................................................................................... 1|
||2.1<br>Table of Figures ..................................................................................................... 2|
|3|Ag102 Product Selector†.............................................................................................. 3|
|4|Pin Description ............................................................................................................. 4|
|5|Functional Description .................................................................................................. 5|
||5.1<br>Operation ............................................................................................................... 5|
||5.2<br>Input ...................................................................................................................... 6|
||5.3<br>Capacity Select ...................................................................................................... 7|
||5.4<br>Thermal Compensation ......................................................................................... 8|
||5.5<br>Status Output......................................................................................................... 9|
||5.5.1<br>Mode 0 – Normal Operation ......................................................................... 10|
||5.5.2<br>Mode 1 – Battery Capacity Warning ............................................................. 10|
||5.5.3<br>Mode 2 – Defective or Disconnected battery ................................................ 11|
||5.5.4<br>Mode 3 – Over Temperature ........................................................................ 11|
||5.5.5<br>Mode 4 – Over Current ................................................................................. 11|
|6|Typical Application ...................................................................................................... 12|
|7|Operating Temperature Range ................................................................................... 13|
|8|Protection ................................................................................................................... 13|
||8.1<br>Battery Reversal Protection ................................................................................. 13|
||8.2<br>Over Current & Short Circuit Protection ............................................................... 13|
||8.3<br>Over Temperature Protection .............................................................................. 13|
||8.4<br>Low Battery Terminal Voltage Protection ............................................................ 13|
|9|Electrical Characteristics ............................................................................................ 14|
||9.1<br>Absolute Maximum Ratings*................................................................................ 14|
||9.2<br>Recommended Operating Conditions .................................................................. 14|
||9.3<br>DC Electrical Characteristics* .............................................................................. 14|
|10<br>Package .................................................................................................................. 15||



## **2.1 Table of Figures** 

Figure 1: Block Diagram with External Components ............................................................ 3 Figure 2: Ag102 SIL Package Format .................................................................................. 4 Figure 3: Basic Ag102 Charge Profile .................................................................................. 5 Figure 4: Input Connections – DC or AC Input ..................................................................... 6 Figure 5: Capacity Select ..................................................................................................... 7 Figure 6: Output Adjustment ................................................................................................ 8 Figure 7: STAT Output Configurations ................................................................................. 9 Figure 8: STAT Output Timing ........................................................................................... 10 Figure 9: Typical Application .............................................................................................. 12 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **3 Ag102 Product Selector[†]** 

|Part Number|Input Voltage|Output Voltage|Battery Capacity|Marking|Package|
|---|---|---|---|---|---|
|Ag102S|9Vto 36V|12V|1.2Ahto7Ah|Ag102|SIL|
|† The Ag102 fully meets the requirements of the RoHS directive 2002/95/EC on the restriction of hazardous substances<br>equipment.|||||in electronic|



## **Table 1: Ordering Information** 

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Ag102<br>Input PWR Vin+ Bat+<br>DC:DC<br>Battery Monitor<br>+ Internal  Converter<br>Reference<br>470uF Voltage<br>Input GND GND Current Sense &  Bat-<br>Polarity Protection<br>CS<br>Capacity Select μ-Controller<br>Thermal THERM<br>Management<br>STAT<br>*Note: Default to 1.2Ah<br>**----- End of picture text -----**<br>


## **Figure 1: Block Diagram with External Components** 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **4 Pin Description** 

|**Pin**|**Name**|**Description**|
|---|---|---|
|1|VIN+|**Positive Supply (Input).**This pin connects to a positive dc<br>supply (9Vto 36V).|
|2|VIN+|**Positive Supply (Input).**This pin connects to a positive dc<br>supply (9Vto 36V).|
|3|CS|**Capacity Select (Input).**This pin connects to an external resistor<br>to set the capacity ofthe battery to be charged (1.2Ahto7Ah).|
|4|STAT|**Charge Status (Output).**This output pin is used to indicate the<br>battery status.|
|5|GND|**Ground Return (Input).**This pin connects to the ground return<br>ofthe powersupply.|
|6|GND|**Ground Return (Input).**This pin connects to the ground return<br>ofthe powersupply.|
|7|THERM|**Thermistor (Input).**The pin can be connected to an external<br>Thermistorto add temperature compensation(if required).|
|8|BAT-|**Battery Negative (Output).**The output pin connects to the<br>battery negative terminal. It must NOT be connected directly to<br>the GNDpin.|
|9|BAT-|**Battery Negative (Output).**The output pin connects to the<br>battery negative terminal. It must NOT be connected directly to<br>the GNDpin.|
|10|BAT+|**Battery Positive (Output).**The output pin connects to the<br>battery positive terminal.|



**Figure 2: Ag102 SIL Package Format** 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **5 Functional Description** 

## **5.1 Operation** 

When power is applied, the Ag102 reads the CS input and sets the charge profile for the selected battery capacity (see Section 5.3). 

In many safety critical systems it is essential that the battery is charged quickly with no stress or damage. The Ag102 achieves this using an optimum multi-stage charge cycle, shown in Figure 3. 

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Battery Voltage / Charge Current<br>**----- End of picture text -----**<br>


**Figure 3: Basic Ag102 Charge Profile** 

Battery manufacturers recommend using multi-stage charging to reduce the stress on the battery while giving the shortest possible charge time. 

The Ag102 implements the ideal charging cycle by applying a higher bulk charge voltage for 70% - 80% of the charge cycle and a lower absorption charge voltage for the remaining 20% - 30%.  This is done to prevent the battery from gassing as it approaches full charge. 

Once the battery has reached the optimum level, the Ag102 will continue to top up the battery using an intermittent float charge. 

The charge profile can be further optimised by using thermal compensation (see Section 5.4). 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **5.2 Input** 

The Ag102 has a very wide input range of 9Vdc to 36Vdc, making this module extremely flexible. For stable operation it is recommended to fit a 470μF capacitor across the input pins, as close to these pins as possible. 

The Ag102 can be powered from an AC power supply with the addition of an external bridge rectifier. It is important that the rectified voltage across the input pins is within the 9Vdc to 36Vdc limits, Figure 4 shows examples of both methods. 

For optimum efficiency the input voltage should be set between 12V and 18V. 

**Figure 4: Input Connections – DC or AC Input** 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **5.3 Capacity Select** 

The Ag102 is capable of charging a range of SLA batteries from 1.2Ah up to 7Ah. Setting the CS input couldn’t be easier, all that is required is a resistor between the CS pin and the GND pin, see Figure 5. 

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Ag102<br>CS<br>RCS<br>GND<br>Capacity Select<br>**----- End of picture text -----**<br>


**Figure 5: Capacity Select** 

The CS pin has an internal pull up resistor to a voltage reference which sets the voltage on this pin. This voltage is measured at start-up and the optimum charge profile for the battery is programmed. The value of RCS is shown in Table 2. 

|Battery<br>Capacity (Ah)|RCSResistance<br>(Ohms)*|Min Input<br>Voltage (V)|Voltage at the<br>CS Pin (V)|Bulk Charge Current<br>Limit (A) ±10%|
|---|---|---|---|---|
|1.2|1K ±1%|9|0.5|0.3|
|2|2K7 ±1%|9|1|0.5|
|2.1|4K3 ±1%|9|1.5|0.525|
|2.3|6K8 ±1%|9|2|0.575|
|2.8|10K ±1%|9|2.5|0.7|
|3.2|15K ±1%|12|3|0.8|
|4|24K ±1%|12|3.5|1|
|7|43K ±1%|12|4|1|



**Table 2: Value of RCS** 

> * To prevent damaging the battery it is important that the correct value of RCS is set. If RCS is not fitted, then the Ag102 will default to 1.2Ah capacity. 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **5.4 Thermal Compensation** 

The optimum terminal voltage for the charging process is also dependent on battery temperature.  This is because the electrochemical activity is affected by temperature changes. Therefore, as the temperature rises, the charging voltage should be reduced to prevent overcharge. Likewise as the temperature falls, the charge voltage should be increased to avoid undercharge. In order to attain optimum service life (maximising the life of the battery), the use of temperature compensation is highly recommended. 

The Ag102 make this easy to implement, with only the addition of a low cost Thermistor, connected so the battery temperature can be monitored. The Ag102 measures the THERM pin and will automatically adjust the charge profile to compensate for any changes in battery temperature. 

TH1* shown in Figure 6 is a 47K NTC (Negative Temperature Coefficient) resistor with B25/50 ~4000K. These are inexpensive and readily available in surface mount or bead format. 

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**----- Start of picture text -----**<br>
Ag102<br>THERM<br>BAT+<br>TH1<br>BAT-<br>(Input) GND<br>**----- End of picture text -----**<br>


**Figure 6: Output Adjustment** 

- For correct operation the Thermistor must be in physical contact with the battery. 

When using thermal compensation, if the battery temperature exceeds 50˚C, the Ag102 will shut-down the DC-DC converter and the output status indicator (STAT) will report an over temperature error. 

The Ag102 will default to a 25˚C charge profile if TH1 is not fitted. 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **5.5 Status Output** 

The Ag102 has a status indication output pin ‘STAT’; that can be connected to a μ- controller input (as shown in Figure 7) for full status monitoring. 

## **Figure 7: STAT Output Configurations** 

Note: Figure 7 shows a 47K pull down resistor, this is required to ensure that the open collector output switches correctly (but this is not a critical value), the STAT output can source ~5mA. 

Table 3, shows the different mode conditions of the Ag102: - 

|**Mode**|**Status Mode**|**STAT Output**|
|---|---|---|
|0|Normal Operation|Steady State‘Logic 1’|
|1|Battery Capacity Warning|1 Inverse Pulse|
|2|Defective or Disconnected Battery Error|1 Pulse|
|3|Over Temperature Error|2 Pulses|
|4|Over Current Error|3 Pulses|



## **Table 3: STAT Output Conditions** 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

Figure 8 shows the timing of the STAT output in more detail: - 

**Figure 8: STAT Output Timing** 

## 5.5.1 Mode 0 – Normal Operation 

During a normal charge cycle the ‘STAT’ output will be a steady state ‘Logic 1’ (Mode 0). 

After the Ag102 has entered the float cycle it will periodically check the battery capacity - approximately once an hour. It does this by stopping the top-up pulses for a short duration and checking the battery terminal voltage response. 

If the battery terminal voltage does not drop below the capacity threshold, the Ag102 will resume operation in Mode 0 and the STAT output will remain at a steady state ‘Logic 1’, 

## 5.5.2 Mode 1 – Battery Capacity Warning 

If the terminal voltage drops below the threshold level (during the battery capacity check), then the Ag102 will go into Mode 1. 

In Mode 1 the STAT output will change to indicate a battery capacity low warning by generating an inverse pulse (‘Logic 0’) for ~100ms (then returns to ‘Logic 1’). The interval between these (inverse) pulses can vary, but will usually be < 10 seconds. 

It is important to remember that even if the Ag102 detects a low battery capacity it will continue to charge the battery. Mode 1 is a warning that the battery capacity is getting low and that the battery may need to be changed. 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

If the Ag102 detects an error condition (Modes 2 to 4), then the STAT output will go to ‘Logic 0’ for 1 second then will send ‘Logic 1’ pulse(s) with a ~200ms mark (and a ~200ms space between pulses), which will be repeated with ~1 second gap (Mode 3 does have an exception to this which is described in Section 5.5.4). 

## 5.5.3 Mode 2 – Defective or Disconnected battery 

If the battery is disconnected, has been deep discharged* or is completely defective, the Ag102 will go into Mode 2 and cycle here until a healthy battery is connected. When a healthy battery is reconnected the Ag102 will return to Mode 0 (normal operation) unless the Ag102 detects a problem. 

*Note: Sealed lead acid battery manufacturers do not recommend deep discharge, as this damages the battery (greatly reducing its life). 

The battery datasheet should be consulted to define the discharge curves and the discharge cut-off voltage. 

Application Note AN102-6 gives an example of a deep discharge protection circuit. 

## 5.5.4 Mode 3 – Over Temperature 

If a battery over temperature condition occurs, the Ag102 will shutdown its DC-DC converter to protect the battery and will go into Mode 3. The STAT pin will output five sets of two pulses with the standard 1s delay in between each set of pulses. But after the fifth set of pulses, the Ag102 will restart to check the temperature during an extended ‘Logic 0’ period (> 3seconds). If the battery is still over temperature the Ag102 will shut down and continue to cycle on Mode 3. When the Ag102 detects that the battery temperature has dropped below 50˚C (the maximum operating temperature), the part will return to Mode 0 (normal operation). 

## 5.5.5 Mode 4 – Over Current 

If an output over current condition is detected, the Ag102 will again shutdown its DC-DC converter and will go into Mode 4. This is considered to be a major fault condition and the Ag102 will need to be power cycled to resume normal operation to protect the battery and itself. 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **6 Typical Application** 

Figure 9 shows a very simple method of connecting the Ag102. 

When the input power is applied RL1 activates and the input is connected directly to the output, the Ag102 will power up and charge the battery. C1 should be positioned as close to the input pins as possible and TH1 should be in physical contact with the battery. 

If the power fails then RL1 will deactivate and the battery will be connected to the output. This configuration will momentarily break the output power. If this is not suitable then alternative configurations are available (please contact Silver Telecom Ltd for more details). 

It is also very important that the GND and Bat- pins are not connected together. Other application drawings using a single pole change-over relay or solid state switching (MOSFET) are also available. 

**Figure 9: Typical Application** 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **7 Operating Temperature Range** 

For most applications the Ag102 will be position close to the battery and the maximum operating temperature will be limited by the battery to 50˚C. However if the battery is being charged remotely, then under certain conditions the Ag102 can be run at higher temperatures (please contact Silver Telecom Ltd for more details). 

## **8 Protection** 

The Ag102 offers three primary protection circuits: - 

## **8.1 Battery Reversal Protection** 

If the battery connections are accidently reversed, the Ag102 will not power the DC-DC converter and the output status indicator (STAT) will report a battery disconnected condition. The Ag102 is internally protected from damage by reverse battery connection. 

## **8.2 Over Current & Short Circuit Protection** 

The Ag102 output has over current (and short circuit) protection. This is triggered when the output current exceeds 200mA above the bulk charge current shown in Table 2. If an over current fault is detected, the Ag102 will shut-down the DC-DC converter and the STAT output will report an over current error. 

## **8.3 Over Temperature Protection** 

This is only activated when using thermal compensation. If the battery temperature exceeds 50˚C, the Ag102 will shut-down the DC-DC converter and the STAT output will report an over temperature error. 

## **8.4 Low Battery Terminal Voltage Protection** 

If the battery terminal voltage is <7V, the Ag102 Status output will report Mode 2 and the Ag102 will remain idle. 

This is primarily to protect the user from accidentally connecting a 6V battery to the Ag102. It also protects the Ag102 from being connected to a damaged or a deep discharged battery. 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **9 Electrical Characteristics** 

## **9.1 Absolute Maximum Ratings*** 

||**Parameter**|**Symbol**|**Min**|**Max**|**Units**|
|---|---|---|---|---|---|
|1|DC Supply Voltage|VCC|-0.3|40|V|
|2|Storage Temperature|TS|-40|+100|°C|



*Exceeding the above ratings may cause permanent damage to the product.  Functional operation under these conditions is not implied. Maximum ratings assume free airflow. 

## **9.2 Recommended Operating Conditions** 

||**Parameter**|**Symbol**|**Min**|**Typ**|**Max**|**Units**|
|---|---|---|---|---|---|---|
|1|Input Supply Voltage|VIN|9|12|36|V|
|2|Operating Temperature|TOP|-20|25|50†|Ta /°C|



†See Section Operating Temperature Range 

## **9.3 DC Electrical Characteristics*** 

||**DC Characteristic**|**Sym**|**Min**|**Typ***|**Max**|**Units**|**Test**<br>**Comments**|
|---|---|---|---|---|---|---|---|
|1|Bulk Charge Constant<br>Current|IOUT||See<br>Table2||A||
|2|Absorption Charge<br>Voltage1|VOUT1‡|14.2|14.4|14.6|V||
|3|Absorption Charge<br>Voltage 2 & Float<br>ChargeVoltage|VOUT2‡|13.5|13.65|13.8|V||
|4|Battery Capacity<br>ThresholdVoltage|VTH||12.9||V|After 2 mins|
|5|STAT<br>Output Low Voltage<br>OutputHigh Voltage|VOL<br>VOH|4.5||0.5|V<br>V|With external<br>47K pull-<br>down resistor|
|6|Output Ripple and Noise<br>(at the battery terminal)|VRN||100||mVp-p|7Ah battery|
|7|DC-DC Converter<br>Efficiency|EFFDC||88||%||
|8|Charger Efficiency|EFFBAT||86||%||
|9|Short-Circuit Duration|TSC|||∞|sec||



*Typical figures are at 25°C with a nominal input voltage = 12V and are for design aid only.  Not Guaranteed ‡Measured between the GND and the BAT+ pins 

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**Ag102** Sealed Lead Acid Battery Charger Module 

V1.6 June 2014 Data Sheet 

## **10 Package** 

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**----- Start of picture text -----**<br>
11.0<br>(max) 56.0<br>Ag102<br>1<br>3.0<br>0.6 ± 0.05<br>8.0 (max) 1.8 ± 0.25 2.54 ± 0.05 30.48 ± 0.25 0.6 ± 0.05<br>(Recommended PCB hole diameter = 1.1 ± 0.05)<br>Dimensions (in mm) are nominal unless otherwise stated<br>14.0<br>**----- End of picture text -----**<br>


Information published in this datasheet is believed to be correct and accurate. Silver Telecom assumes no liability for errors which may occur or for liability otherwise arising out of use of this information or infringement of patents which may occur as a result of such use. No license is granted by this document under patents owned by Silver Telecom or licensed from third parties by Silver Telecom. The products, their specification and information appearing in this document are subject to change by Silver Telecom without notice. 

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