500 mA, Ultralow Noise, High PSRR, Low Dropout Linear Regulator

The ADP7185 is a complementary metal oxide semiconductor (CMOS), low dropout (LDO) linear regulator that operates from −2.0 V to −5.5 V and provides up to −500 mA of output current. This high output current LDO is ideal for regulation of high performance analog and mixed signal circuits operating from −0.5 V down to −4.5 V. Using an advanced proprietary architecture, the ADP7185 provides high power supple rejection ratio (PSRR) and low noise, and it achieves excellent line and load transient response with a small 4.7 μF ceramic output capacitor.

The ADP7185 is available in 15 fixed output voltage options. The following voltages are available from stock: −0.5 V, −1.0 V, −1.2 V, −1.5 V, −1.8 V, −2.0 V, −2.5 V, −3.0 V, and −3.3 V.

Additional voltages available by special order are −0.8 V, −0.9 V, −1.3 V, −2.8 V, −4.2 V, and −4.5 V. An adjustable version is also available which allows output voltages that range from −0.5 V to −VIN + 0.5 V with an external feedback divider.

The enable logic feature is capable of interfacing with positive or negative logic levels for maximum flexibility.

The ADP7185 regulator output noise is 4 μV rms independent of the output voltage. The ADP7185 is available in an 8-lead, 2 mm × 2 mm LFCSP, making it not only a very compact solution but also providing excellent thermal performance for applications requiring up to −500 mA of output current in a small, low profile footprint.

Applications

* Regulation to noise sensitive applications: analog-to-digital converters (ADCs), digital-to-analog converters (DACs), precision amplifiers

* Communications and infrastructure

* Medical and healthcare

* Industrial and instrumentation

* Input voltage range: −2.0 V to −5.5 V

* Maximum output current: −500 mA

* Fixed output voltage options: −0.5 V to −4.5 V

* Adjustable output from −0.5 V to −VIN + 0.5 V

* Low output noise: 4 μV rms from 100 Hz to 100 kHz

* Noise spectral density: 20 nV/√Hz, 10 kHz to 1 MHz

* PSRR at −500 mA load

* 68 dB at 10 kHz

* 50 dB at 100 kHz

* 40 dB at 1 MHz

* Low dropout voltage: −190 mV typical at −500 mA load

* Initial output voltage (VOUT) accuracy: ±0.5%

* Output voltage accuracy over line, load, and temperature: ±2.2%

* Operating supply current (IGND): −0.6 mA typical at no load

* Low shutdown current: −2 μA typical at VIN = −5.5 V

* Stable with small 4.7 μF ceramic input and output capacitor

* Positive or negative enable logic

* Current-limit and thermal overload protection

* 8-lead, 2 mm × 2 mm LFCSP package