1.2 V Ultralow Power High PSRR Voltage Reference

The ADR280 is a 1.2 V band gap core reference with excellent line regulation and power supply rejection designed specifically for applications experiencing heavy dynamic supply variations, such as data converter references in GSM, GPRS, and 3G mobile station applications. Devices such as the AD6535 that have an analog baseband IC with on-board baseband, audio codecs, voltage regulators, and battery chargers rely on the ability of the ADR280 to reject input battery voltage variations during RF power amplifier activity.

In addition to mobile stations, the ADR280 is suitable for a variety of general-purpose applications. Most band gap references include internal gain for specific outputs, which simplifies the user’s design, but compromises on the cost, form factor, and flexibility. The ADR280, on the other hand, optimizes the band gap core voltage and allows users to tailor the voltage, current, or transient response by simply adding their preferred op amps.

The ADR280 operates on a wide supply voltage range from 2.4 V to 5.5 V. It is available in compact 3-lead SOT-23 and SC70 packages. The device is specified over the extended industrial temperature range of −40°C to +85°C.

APPLICATIONS

* List GSM, GPRS, 3G mobile stations

* Portable battery-operated electronics

* Low voltage converter references

* Wireless devices

* 1.2 V precision output

* Excellent line regulation: 2 ppm/V typical

* High power supply ripple rejection: –80 dB at 220 Hz

* Ultralow power supply current: 16 μA maximum