Panasonic EB-GD93, Service Manual

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TEST AND MEASUREMENT
Issue 1 Section 6 MCUK001002C8
Revision 0 – 54 – Service Manual
Figure 6.33: Charging calibration 4
Current Charging ADC Calibration
It is important to monitor the current when charging the Li-ion battery, both to protect against over-current and to determine
when charging is complete. The telephone uses the VCC3 and MADC (ICHG) connections of OMEGA to measure charging
current as an amplified voltage across a sense resistor.
NOTE:
This calibration procedure MUST be carried out once Charging Voltage calibration has been completed.
1. Press F4 and select VIEW ADC LINES. Read ADIN5 (CRG CURRENT) and record this value.
Figure 6.34: ADC Calibration
2. If this value is outside the range 101 - 251, then there is a fault and further investigation is required. Otherwise, calculate
the difference between the recorded value and the theoretical value of 161. Record this value for use later.
3. Press F6 and select TRIM OTHER. Select COMP OFFSET and enter the value recorded in step 2.
4. Press F9. Wait for the prompt “Saving EV Trim data” to disappear, turn OFF the power supplies and disconnect the
telephone.