Other Parts Discussed in Thread: SN74ALVCH16543
I have a PCB design with 72 of these parts on the same board, fed with a single 3.3v power supply. On power-up, I often see the power supply limiting at 4A, which is due to one ore more of these ICs crowbaring the current, and not powering-up correctly. For now, there are no other parts on this PCB.
I used a lab power supply and slowly raised the Vcc manually (vs. using the switching voltage regulator on the board) and managed to power-up properly a few times where Icc was 800mA (for all 72 parts). Most of the time, when I power-up slowly (or fast) the crowbar current starts at about 1.8v, and the current goes up quickly as I raise Vcc higher.
The control inputs are configured as:
OE = 0 (hard tied to GND)
DIR = HIGH (driven from another SN74LVTH16646 buffer IC with his input tied high through a pull-up and configured as a simple buffer, but with same Vcc)
SAB = SBA = HIGH (driven from another SN74LVTH16646 buffer IC with his input tied high through a pull-up and configured as a simple buffer, but with same Vcc)
Abus = 10Kohm pull down resistors to GND
Bbus = open circuit (outputs)
Does this part have any sort of special power-up issue?
Actual P/N is SN74LVTH16646DGGR (TSSOP package)
