ZSSC1750 Datasheet, PDF (55/116 Pages) Integrated Device Technology – Data Acquisition System Basis Chip

ZSSC1750 / ZSSC1751 Datasheet
To go to the LP or ULP State and perform measurements of discrete current, voltage, and internal temperature,
the following tasks must be done:
• Enable at least one of the following interrupts:
 Set irqEna[0] to 1 to enable the watchdog interrupt to wake up the system.
 Set irqEna[1] to 1 to enable the sleep timer to wake up the system.
 Set irqEna[4] to 1 to enable LIN wake-up detector and to enable the system to wake up due to a LIN
wakeup frame (for ZSSC1750).
 Enable any ADC interrupt (see section 3.6.1.1).
• Configure the sleep timer compare value (register sleepTCmp) if needed.
• Set up the ADC trigger timer compare value (register sleepTAdcCmp) as needed.
• Configure the pwrCfgLp register as follows:
 Set pdState to 0 or 1 to configure the LP State or to 2 to configure the ULP State.
 Set pdMeas to 2 to configure the system to perform discrete current, voltage, and internal temperature
measurements.
 Set lpEnaLp, ulpEnaLp and pwrRefbufOcLp as needed.
• Set discCvtCnt as needed. This register defines the number of current-only measurement loops before
performing measurements of all three parameters.
• Write A9_HEX to register gotoPd and then drive the CSN line high.
When an enabled interrupt occurs, the system wakes up and the settings from register pwrCfgFp are restored.
When all blocks have stabilized, the external microcontroller clock is re-enabled and if coming out of the ULP
State, the microcontroller reset is released.
Important: If any measurement is active while an enabled interrupt occurs (e.g., the sleep timer expires) the
measurement is interrupted and the system returns to the FP State.
Note: If register discCvtCnt is set to 0, voltage and temperature are measured in each loop (default setting).
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April 20, 2016