Hi guys,
I'm trying to make schematics from all SNES cartridges I have and I started by the "easiest": Super Mario World. The board is labeled as SHVC-1A1B-06, with SRAM but no MAD-1.
In this board, SRAM is powered by a diode during stand-by, and its /CS is driven by some weird device labeled as D2145U. I deeply searched in Google but nothing appears, altough I get to figure out that it could be PNP BJT transistor.
Does anybody know what it really is? This is the schematics:
If you analyze the schematic assuming it is a PNP transistor, the circuit makes no sense at all and it can't drive /CS to high when Vcc disappears.
Is there any alternate way to put SRAM to standby mode without using MAD-1?
I'm trying to make schematics from all SNES cartridges I have and I started by the "easiest": Super Mario World. The board is labeled as SHVC-1A1B-06, with SRAM but no MAD-1.
In this board, SRAM is powered by a diode during stand-by, and its /CS is driven by some weird device labeled as D2145U. I deeply searched in Google but nothing appears, altough I get to figure out that it could be PNP BJT transistor.
Does anybody know what it really is? This is the schematics:
If you analyze the schematic assuming it is a PNP transistor, the circuit makes no sense at all and it can't drive /CS to high when Vcc disappears.
Is there any alternate way to put SRAM to standby mode without using MAD-1?