App note: Connecting LDOs in parallel

App note from ROHM semiconductor on combining LDOs for higher load capacity. Link here (PDF) When you want to increase the output current capacity of an LDO, or when the power dissipation of a single LDO is insufficient, you might think of connecting LDOs in parallel if you need to disperse the dissipation using two […]

App note: Capacitor selection guidelines on LDOs

They are different kind of capacitors, selection for one capacitor varies depending on application. A good read app note from Analog Devices. Link here (PDF) Capacitors are underrated. They do not have transistor counts in the billions nor do they use the latest submicron fabrication technology. In the minds of many engineers, a capacitor is […]

App note: Low drop out, phase margin, and stability

Old app note from Fairchild Semiconductor about external component effects on LDOs. Link here (PDF!) Low drop-out (LDO) regulators are one of the basic building blocks of most power supplies used in today’s electronics. Their ease of use, low cost, and small size makes them ideal in portable and handheld applications. They are available in […]

App note: How to successfully apply low dropout regulators

Application note regarding proper usage of LDO from Analog Devices. Link here (PDF) A low dropout (LDO) regulator is capable of maintaining its specified output voltage over a wide range of load currents and input voltages, down to a very small difference between input and output voltages. This difference, known as the dropout voltage or […]

App note: Green LED replaces LDO regulator

App note(PDF) from MAXIM using a green LED as LDO for low power application Insystems in which a microcontroller must communicate with peripheral devices that operate at different supply voltages, a level translator may be necessary. This design idea explains how for lowpower loads, a single green LED can replace a 1.8V LDO regulator in […]

App note: An introduction to LDO early warning function

Supervisory reset delay prevents premature power fail resets, App note from ON Semiconductor. In today’s world of high speed, high power processors, new demands have been placed on the power source regulator. One example is the need to inform the processor in advance of an impending drop in supply voltage below a critical value. A […]

App note: Design considerations for 5V to 3.3V pass regulators

Great app note from Micrel on thermal management for voltage regulators. This note discusses the LDO option, including choosing between simple three terminal regulators and full-featured five terminal regulators, and provides formulas, calculations, and a selection of commercial heat sinks for powering 3.3V logic circuitry requiring up to 5 amps from a standard +5V supply. […]

TS3300 switching regulator coupled with an LDO in same package

Steve Taranovich has posted this review of the TS3300 switching regulator coupled with an LDO in same package:    Touchstone, with its first analog power management product, has enhanced such a function with the capability to use supply voltages down to 0.6V while still being able to deliver a 75 mA output current. The device […]

App Note: Thermal considerations for low-dropout regulators

Here’s an app note from Microchip aimed at shedding some light into power dissipation and heat-sinking of low-dropout regulators. Basically all power that is dissipated from LDOs is turned into heat. This article describes what to look for in datasheets to calculate if, and what kind of cooling your devices need. LDOs specify maximum output […]

App note: Noise sources in low dropout (LDO) regulators

Looking for a clean power supply for a sensitive analog circuit? Analog Devices describes the sources of noise in LDO voltage regulators, and provides some examples to limit and combat the noise. In general, LDO noise comprises two components: intrinsic, or internally generated noise, and extrinsic, or externally generated noise. Thermal and 1/f noise are […]