AS13985F12-T

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Overview

The AS13985F12-T is a micropower low-dropout linear regulator (LDO) manufactured by ams-OSRAM USA INC. It provides a fixed 1.2V output with a maximum current of 150mA. The device operates within an input voltage range of 2.5V to 5.5V and features ultra-low dropout voltage, typically 45mV at full load. It guarantees stability with ceramic output capacitors ranging from 1µF to 22µF. The quiescent current is 95µA in active mode and drops below 1µA during shutdown. Output noise can be reduced to 30µV RMS using a bypass capacitor.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Feature Summary

• Ultra-low dropout voltage ensures high efficiency under low headroom conditions
• Integrated over-current and over-temperature protection safeguards the circuit
• Low-noise architecture supports direct connection to sensitive analog components
• Automatic sleep mode minimizes power consumption in standby applications

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Applications

• Mobile phones
• Personal Digital Assistants (PDAs)
• MP3 players
• Handheld computers
• Digital cameras

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Procurement Notes

Verify that the component matches the specific 1.2V fixed output variant designated by the F suffix. Confirm the package type corresponds to the 5-bump Wafer Level Package (WLP). Ensure the ordering code includes the -T suffix for tape and reel delivery format. Cross-reference the marking code ASKN on the device surface to validate authenticity against official datasheet specifications.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Selection Notes

Select this LDO when designing battery-powered portable electronics requiring stable 1.2V rails. It is suitable for powering logic circuits or RF sections where low noise and minimal footprint are critical. The WLP package offers space savings compared to traditional SOT23 options. Ensure the application utilizes ceramic capacitors between 1µF and 22µF to maintain loop stability across all operating temperatures.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Part Context

This component belongs to the AS13985 series of micropower LDOs designed for mobile and handheld devices. The series offers multiple fixed output voltages ranging from 1.2V to 5.0V in 25mV steps. All variants share identical electrical characteristics regarding dropout voltage, current capability, and protection features, differing only in their regulated output levels and corresponding package markings.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Replacement Considerations

Compatible substitutes include other parts from the AS13985 family with different output voltages if system requirements change. Verify pin compatibility between the 5-bump WLP and alternative packages like SOT23 if layout modifications are permitted. Ensure any replacement maintains the required 150mA continuous current rating and low ESR capacitor stability.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators FAQ

What is the minimum recommended output capacitance for stability?

The device is guaranteed stable with ceramic output capacitors having a capacitance value between 1µF and 22µF.

How does the BYPASS pin affect performance?

Connecting a 10nF capacitor to the BYPASS pin reduces the output noise voltage to 30µV RMS, allowing direct connection to noise-sensitive circuits without additional filtering.

What happens when the Enable (EN) pin is pulled low?

Pulling the EN pin low activates automatic sleep mode, reducing the quiescent current to less than 1µA and disabling the regulated output.