Ag102 Evaluation Board User Manual
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4.4 Simulated Thermal Offset
During Float charge SW1 can be used to demonstrate how the voltage changes to
compensate for the change in battery temperature if an appropriate thermistor is fitted.
With both switch positions open, the Ag102 will default to a 25ºC ambient charge
voltage.
When switch No. 1 is closed R1 (220K) this will simulate a battery temperature lower
than 25ºC and the output voltage will be increase.
When switch No. 2 is closed (18K) this will simulate a battery temperature higher than
25ºC and the output voltage will decrease (this response will be slow when the Ag102 is
float charging).
When both switches are closed this will simulate a battery temperature higher than
50ºC, the output will switch OFF and the over temperature error LED (5) will illuminate.
Opening one or both switches will return the Ag102 to its normal charge mode.
4.5 Status Output
The Ag102 status output pin is connected to a PIC10F200 µ-controller as detailed in the
application note “AN102-3”. The EVALAg1x2 board used a 3-8 decoder IC (74HC138)
to drive LEDs (2 to 9) displaying the status of the Ag102 (see Figure 3).
1. When the battery is charging LED9 (Normal Charge) will be illuminated.
2. When the Ag102 detects a low battery capacity, it will continue to charge the
battery and LED3 (Battery Capacity Warning) will be illuminated.
3. When the battery is disconnected the Ag102, LED4 will be illuminated.
4. When the Ag102 detects the (simulated) thermistor has exceeded 50ºC, it will
stop charging the battery and LED5 (Over Temperature) will be illuminated.
When the Ag102 detects that the battery temperature has dropped back below
50ºC, it will resume charging the battery (as shown in No.1 above)
