Diodes Incorporated Announces AP7372 Low-Noise LDO with 90dB PSRR for Precision Systems

The AP7372 is a low-dropout (LDO) regulator from Diodes Incorporated, designed for applications that need low noise and high power supply ripple rejection (PSRR) like data converters, VCOs, and PLLs. It reaches up to 90dB PSRR across a wide range of frequencies and delivers output noise as low as 8μVrms, making it a good fit for sensitive systems in test and measurement, communications, industrial automation, and medical devices. 

Up to 200mA output current is supported with a dropout voltage of 120mV. Five variants of the regulator are available with fixed outputs of 1.8V, 2.5V, 3.3V, and 5.0V, and one adjustable version supporting down to 1.2V. The wide 2.7V to 20V input range means it works with typical 5V and 12V supplies, plus it'll run on battery power, including single Li-Ion cells. Adjustable soft-start time, set with an external capacitor, lets you optimize power-rail ramp-up to mitigate inrush currents. A current limiter protects against short-circuit and overcurrent, while thermal protection is built in. A 2.2μF ceramic output capacitor ensures stability.

It’s designed to be compact and requires just input and soft-start capacitors. The LDO is housed in a 1.2mm × 1.0mm U-WLB1012-6 (Type A1) ball-grid array package. An enable pin supports power sequencing and system-level power control. Shutdown current is around 3μA, and quiescent current is 66μA, keeping overall power consumption low. The AP7372 is priced at $0.30 each in quantities of 1,000.

Key Features of AP7372 LDO

• Up to 90dB PSRR across wide frequency range

• Extremely low 8μVrms output noise

• 200mA output current capability

• 120mV dropout voltage

• 2.7V to 20V input voltage range

• Five fixed outputs: 1.8V, 2.5V, 3.3V, 5.0V

• Adjustable output down to 1.2V

• Resistor-divider pin for fine output adjustments

• Adjustable soft-start with external capacitor

• Current limiter for short-circuit and overcurrent protection

• Built-in thermal protection

• Only needs 2.2μF ceramic output capacitor for stability

• Tiny 1.2mm x 1.0mm U-WLB1012-6 package

• Enable pin for power sequencing and control

• 3μA shutdown current

• 66μA quiescent current

• Low bill of materials design

Applications of AP7372 LDO

• Data converters (ADCs, DACs)

• Voltage-controlled oscillators (VCOs)

• Phase-locked loops (PLLs)

• Test and measurement equipment

• Communication systems

• Industrial automation

• Medical equipment

• Precision analog circuits

• Battery-powered devices

• 5V and 12V bus-powered systems