ZHCSTD7A December 2021 – November 2023 BQ79631-Q1
PRODUCTION DATA
Pins | Components | Value | Description |
---|---|---|---|
V9, V8, TSREF | Resistor string Top | 1.32 MΩ | Resistor divider to divide down HV+ measurement to ADC input range. Component values are recommended ones. Other values can be chosen as long as signal is kept within ADC input range. Too large of value resistors will cause more measurement inaccuracy due to leakage at ADC pins. |
Resistor string Bot | 12.45 kΩ | ||
V8, V7, TSREF | Resistor string Top | 5 kΩ | Resistor divider to divide down HV- measurement to ADC input range. Component values are recommended ones. Other values can be chosen as long as signal is kept within ADC input range. Too large of value resistors will cause more measurement inaccuracy due to leakage at ADC pins. |
Resistor string Bot | 10 kΩ | ||
GPIO2 | Optional MOSFET or Switch (SW1 and SW2) | 1000-V standoff | Switch to block unwanted leakage current. |
CHARGE +/- Measurement is shown in Figure 9-5.
Differential ADC inputs V9-V8 measure the CHARGE+ voltage. The CHARGE+ voltage can be determined from the output of the ADC by using:
Differential ADC inputs V8-V7 measure the CHARGE– voltage. The CHARGE– voltage can be determined from the output of the ADC by using:
Resistors R2 is in parallel with R3, R5 is in parallel with R4 to ensure that VS9 and VS7 are not disconnected from the resistor string in case of failure in any one of these resistors. VS9 and VS7 could exceed abs max if they get disconnected from the resistor string.