3-wire Realtime Clock S-35192A

The S-35192A is a low-current-consumption 3-wire CMOS real-time clock IC that features a wide operating voltage range (1.3 V to 5.5 V) and can be driven on a variety of supply voltages, from a main supply to a backup supply. The time keeping current consumption of 0.45 µA and time keeping operation voltage of 1.1 V enable greatly increased battery duration. In a system that operates on a backup battery, the free register incorporated in the real-time clock can be used for the user backup memory function. The user register can hold data on a supply voltage as low as 1.2 V (min.), so the data stored in the register before the main power supply was cut can be called any time after the voltage is restored. This product also includes a clock adjustment function that enables wide-ranging correction of deviation in the frequency of the crystal oscillator at a minimum resolution of 1 ppm. Also, by combining this function with a temperature sensor, the clock adjustment value can be set in accordance with changes in the temperature, which makes it possible to realize a clock function that retains a high degree of accuracy regardless of temperature variation.


Low current consumption
0.45 µA typ. (Vdd =3.0 V, Ta =25°C)
Constant 32 kHz clock pulse output (Nch open-drain output)
Wide operating voltage range
1.3 to 5.5 V
Time keeping operation voltage
1.1 V
Built-in clock adjustment function
Built-in free user register
3-wire (micro wire) CPU interface
Built-in alarm function
Built-in flag generator at power down or power on
Auto calendar up to the year 2099, automatic leap year calculation function
Built-in constant voltage circuit
Built-in 32 kHz crystal oscillator circuit (Cd built in, Cg external)
Lead-free products


  • Digital still cameras
  • Digital video cameras
  • Electronic power meters
  • DVD recorders
  • TVs, VCRs
  • PHS
  • Mobile phones
  • Car navigation

Standard Circuit

Standard Circuit