Hello all,
The datasheet for BQ76PL536A recommends using 100K pull-up resistors on the SDI_H and SCLK_H pins on the base IC:
The pins of the base IC (only) in a stack should have the SCLK_H and SDI_H pins terminated with pullups to
minimize current draw of the part if the host ever enters a state where the pins are not driven, i.e., held in the
high-impedance state by the host. In non-base devices, the _H pins are forced to be all outputs driven low when
the HSEL pin is high. In non-base devices, all _H pins should remain unconnected.
The CS_H has a pullup resistor of approximately 100 kΩ. SDO_H is a 3-state output and is terminated with a
weak pullup.
The reference circuit in the same datasheet does not have these pull-ups.
The EVM schematic for the BQ76PL536 provided by Roger Hwang (ICs are labeled BQ76PL536B (rev. B?) has 10K pull-down resistors on SDI_H, SCLK_H, and CONV_H.
Which is correct, pull-ups or pull-downs? Does it matter? Do I also need a pull-up/pull-down on CONV_H? Do I need one on CS_H?
Thanks,
Matthew B.
