Latch uses 555 in memory mode

The familiar Type 555 can be used to switch currents up to 200 mA. Less well-known is its use as a latch with control input. When the input pins 2 (trigger) and 6 (threshold) are linked and connected to half the supply voltage, the output can be switched as follows. When the potential at pins 2 and 6 is raised to full supply voltage level, the output is switched to ground. When pins 2 and 6 are linked to ground potential, the output assumes supply voltage level .