CAT1023LI-25-G

PMIC - Supervisors: CAT1023LI-25-G Application Field and Working Principle

PMIC, also known as Power Management IC, is an integrated circuit (IC) that supplies power and manages current of electronic devices. Often used in battery-powered, portable electronic systems and integrated components, PMICs provide the electrical core that enables applications such as computer systems, telecommunications, data processing, medical instrumentation, powerful gaming platforms and other electronics-based products. Supervisors are an important part of the PMIC family. Supervisors provide the device management functions associated with system on off and reset, power on reset, power fail monitor, and system voltage monitor.

The CAT1023LI-25-G is a low-dropout reset supervisor specially designed for use in portable applications such as cellular phones and digital still cameras. With a very low quiescent current and guaranteed reset accuracy, along with an extended operating range, the CAT1023LI-25-G is the ideal choice for power supply monitoring and system reset.

Application Field

The CAT1023LI-25-G is used in a variety of power restricted and mobile designs. It is suitable for cellular phones and digital still cameras, or any portable device powered by a battery or a low-voltage power supply. As an IC designed for near-zero standby current operation, it is also ideal for use in battery-operated applications.

The CAT1023LI-25-G offers low-power operation in a small package size. The package is a tiny SOT-23-5, making it more suitable for space-limited applications. With a wide operating temperature range (−40°C to +85°C) and guaranteed reset accuracy, it provides enhanced and reliable system reset protection.

Working Principle

The CAT1023LI-25-G supervisor is an enable/disable type reset supervisor. It has a built-in enable function that controls the activation of the voltage monitor by the ENB pin. Any system reset function could be implemented by connecting an external reset signal to the RESET pin.

This IC has an on-chip voltage divider that enables the monitoring of voltage levels from any 1.5V to 5.0V power supply. Its operating current is only 1.4µA, and the quiescent current for a 3.2V power supply is 0.1µA, making it ideal for applications that need low power dissipation. A low propagation delay of 5µs makes the CAT1023LI-25-G suitable for high frequency applications.

The reset output of this IC is open-drain. It has an active-low reset logic level. When an assert condition occurs, the output is hold low until it is disabled by the ENB pin. When it is disabled, the reset signal is deasserted.

The reset IC has incorporated adjustable reset time delays. The delay is caused by the internal capacitor discharging. It is possible to extend the delay to 220µs by the external capacitor. The CAT1023LI-25-G has a reset validation window of 240µs, with a reset valid from 30mV up to 250mV. At lower input levels, up to 30mV, the reset is held active for 240µs.

Conclusion

CAT1023LI-25-G is an ideal choice for power supply monitoring and system reset. It has an on-chip voltage divider that is great for monitoring voltage levels from 1.5V to 5.0V power supplies. The low operating current rating and low quiescent current of 1.4µA and 0.1µA respectively, make this IC suitable for low-power applications. Also, the extended operating temperature range and guaranteed reset accuracy provide a reliable system reset protection. The package size of SOT-23-5 further makes it a more suitable choice for space-limited applications.