TS555: single CMOS timer with very low power consumption

ST offers pin-to-pin fully standard-compatible low-power timers, in single and dual independent channel versions.

These devices are highly stable monolithic circuits, generating accurate time delays (monostable mode) or programmable oscillations ( stable mode) with accurate frequency and duty-cycle.
The industry-standard frequency generators are circuits designed in bipolar technology, low frequency and with high power consumption. ST low-power products are designed in CMOS technology, low power and low consumption and can reach high frequency operation up to 2.7 MHz.


Product types:

TS555 and TS556 devices require a voltage supply range within +2V to +16V allowing to work with multiple different voltage rails (3.3V, 5.0V, 12V, etc.). The excellent temperature stability (75ppm/°C) allows small timing shift with ambient temperature variation up to 125°C. ST CMOS low power timers are available in standard plastic SMD packages SO8 and SO14 for single and dual channels, respectively.

Simplified single channel timer block diagram

Simplified single channel timer block diagram


  • High frequency operation up to 2.7 MHz
  • Reduced power consumption
  • Reduced supply current spikes during output transitions
  • Flexible application design from 2V up to 16V power supply
  • Extended temperature range up to 125°C for extreme ambient conditions