LDO regulators aimed at noise sensitive loads

Intersil Corp. has introduced a couple of high performance, single output low-dropout (LDO) voltage regulators that claim to deliver outstanding dropout and transient performance for noise sensitive loads. The ISL80510 and ISL80505 provide 1A and 0.5A of continuous output current and ultra-low dropout of 130mV and 45mV at full load, respectively, detailed the company.

The ISL80510's maximum dropout is nearly 50 per cent lower than the nearest competitor, which enables lower power dissipation in industrial, wired and wireless equipment, added Intersil.

The ISL80510/05 LDOs provide better transient performance with peak-to-peak excursions up to nine times lower than competitive LDOs, the company boasted. This transient performance level and DC accuracy of 1.8 per cent safeguards against voltage undershoots and overshoots to deliver clean point-of-load voltage to CPUs, DSPs and MCUs, which require tight voltage accuracy and low noise. The ISL80510/05's compensation loop provides excellent noise filtering by maintaining a flat power supply rejection ratio (PSRR) response over a range of frequencies.

The ISL80510 operates from input voltages of 2.2V to 6V, and the ISL80505 supports 1.8V to 6V. The output voltage of these LDOs can be adjusted from 0.8V to 5.5V, which enables designers to cover a range of applications such as low power RF amplifiers, communications equipment, industrial process control systems, test instruments, medical equipment and consumer network routers. An adjustable soft-start feature allows designers to control the input inrush current and program the startup time to accommodate any power-up sequencing requirement.

The ISL80510 single-output LDO voltage regulator enables dropout of 130mV at Vout of 2.5V with a 1A load current, while the ISL80505 single-output LDO voltage regulator enables ultra-low dropout of 45mV at Vout of 2.5V with a 500mA load current. Both support stable operation with a small 4.7?F output ceramic capacitor.

According to the company, both devices deliver 卤1.8 per cent Vout accuracy guaranteed over line, load and junction temperature range of -40°C to 125°C. The ISL80510 and ISL80505 LDOs can be combined with the ISL80136 40V/50mA linear regulator, ISL80138 40V/150mA linear regulator, and synchronous step-down DC/DC converters, such as the ISL8117A and ISL8026, to support the bulk power rails in a typical process control industrial application.

The ISL80510 and ISL80505 are available and priced at $0.39 in 1k quantities. Both LDOs are pin-to-pin compatible and supplied in thermally enhanced 8-lead, 3mm x 3mm DFN packages. The ISL80510EVAL1Z evaluation board is available and priced at $20.