Low leakage current methods of initializing pin inputs at power up

gpioinputpulldownpullup

Suppose I have an IC that has a standard level triggered input pin. I need this pin's state to be setup immediately at power on at a time when my MCU's GPIOs may not have established levels. What are my options for accomplishing this while still being able to control the pin level at a later time?

My way that of course comes to mind is using a pull up/down resistor however that can have high leakage current. During the times my MCU is online I will have no use for the resistors as the pin state can be set by the MCU so this leakage is highly undesiable. Are there any options i'm not thinking of?

schematic

simulate this circuit – Schematic created using CircuitLab

Best Answer

I once use megaohm pull downs and very low leakage mosfets as a cmos buffer. Also i think actel's igloo does the job with megaohm pull resistors.