Voltage Regulator Has Low Quiescent Current

Diodes Incorporated has introduced the AP7381. Operating from a wide input voltage spanning 3.3 V to 40 V, this positive voltage regulator offers ultra-low quiescent current and high accuracy, making it well-suited for use in a variety of applications ranging from USB and portable devices to energy meters and home automation.

MFG_AP7381_SOT89The AP7381 is offered with fixed output voltages of 3.3 V or 5 V to power standard logic device supplies and I/O levels and can operate from an input voltage between 3.3 V and 40 V, which covers most common system power rails. The device provides excellent line and load regulation and features a low dropout voltage of typically 1,000 mV for a 3.3 V output device operating at an output current of 100 mA. An internal voltage reference ensures output accuracy at room temperature is maintained within ±2%.

A low quiescent current of just 2.5 µA minimizes standby power in low-power systems and extends the life of battery-operated products. The AP7381 has a built-in current limit and an over-temperature protection (OTP) function and also features over-current protection, provided by an internal current limit circuit. The AP7381 is available in a SOT89 package (on tape and reel) and in a TO92 package (ammo packed).

Diodes Incorporated | www.diodes.com

New LDO Regulators Deliver clean output voltage to MCUs

Intersil Corp. recently launched the SL80510 and ISL80505, which are two new single-output, low-dropout (LDO) voltage regulators that provide impressive dropout and transient performance for noise-sensitive loads. They deliver 1 A and 0.5 A of continuous output current and ultra-low dropout of 130 mV and 45 mV at full load, respectively. The ISL80510’s maximum dropout is approximately 50% lower than the nearest competitor, which enables lower power dissipation in industrial, wireless, and wired equipment.

The LDOs also provide better transient performance with peak-to-peak excursions up to nine times lower than otherLDOs. This transient performance level and DC accuracy of 1.8% 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 wide range of frequencies.ISL80510_Intersil

The ISL80510 operates from input voltages of 2.2 to 6 V. The ISL80505 supports 1.8 to 6 V. Since LDOs’ output voltage can be adjusted from 0.8 to 5.5 V, you can cover a broad range of applications, such as low-power RF amplifiers, communications equipment, and consumer network routers. An adjustable soft-start feature enables you to control the input inrush current and program the start-up time to accommodate any power-up sequencing requirement.

Specifications and features of ISL80510 and ISL80505:

  • ISL80510 provides dropout of 130 mV at Vout of 2.5 V with a 1-A load current
  • ISL80505 provides ultra-low dropout of 45 mV at Vout of 2.5 V with a 500-mA load current
  • Stable operation with a small 4.7-μF output ceramic capacitor
  • Delivers ±1.8% Vout accuracy guaranteed over line, load, and junction temperature range of –40°C to 125°C
  • Programmable output soft-start supports sequencing and helps power supply designer control inrush current
  • Current limit protection and thermal shutdown function safeguards against excessive load current or operating temperature
  • Both LDOs are pin-to-pin compatible and supplied in thermally enhanced 8-lead, 3 mm × 3 mm DFN packages

The ISL80510 and ISL80505 cost $0.39 1,000-unit quantities. The ISL80510EVAL1Z evaluation board costs $20.

Source: Intersil Corp.