I'm trying to use a 555 to generate a reset pulse ~1ms on power application. Have the "usual" configuration with timing cap from pin 2/6 to pin 1 (ground), charging resistor pins 2/6 to Vcc pin 8. As this is a once-off pulse, DISCHARGE pin is open (no function required). RESET is at Vcc, CONTROL is open/bypassed to gnd.
Schematic at
There is also a reverse-biased diode across the timing resistor to discharge the cap when Vcc is removed, to assure that the cap starts below 1/3Vcc.
According to the 7555 sheet, on application of Vcc this *should* give a high output until pin 6 reaches 2/3Vcc, then low output. That assumes that the chip gets its ducks in line before pins 2/6 rise past 1/3Vcc, which shouldn't be a challenge.
In my test, the output is low from the outset. No blip.
Apart from using a 555, what am I doing wrong? I could have done this with a bipolar, two resistors and a cap but I wanted a decent fall time :-(.