I'm having a bit of trouble deciphering how the PWRM pin on the BQ78350 works.
In the datasheet, I see it called out as an open drain connection, but I don't have any info as to what the polarity of it is. Furthermore, the application guide has this statement:
8.5 Power Mode Indication (PWRM)
The PWRM pin can be used to indicate the power mode of the bq78350-R1. The PWRM has the following
conditions:
• PWRM is high:
– bq78350-R1 is in NORMAL mode.
– bq78350-R1 is in SLEEP mode AND GaugeConfiguration[PWRMSleep] = 1.
• PWRM is High-Z:
– bq78350-R1 is in SLEEP mode AND GaugeConfiguration[PWRMSleep] = 0.
– bq78350-R1 prepares to enter SHUTDOWN mode. Once in SHUTDOWN mode, the device has no control over PWRM.
This pin can be used to control other external circuit elements based on the power mode state of the
bq78350-R1.
I assumed an open drain connection indicated that when the pin was high (and thus likely in normal mode) that it would pull it to ground, while it would be high impedance when low. Maybe I'm just missing something but if someone could clear up this pin operation, I would appreciate it!
Thanks!
-Jim
