Key Specs

SpecValueConditionSource
Control FeaturesEnableDigi-Key
Current Quiescent IQ60 µADigi-Key
Input Voltage (Max)5.5VDigi-Key
Mounting TypeSurface MountDigi-Key
Number Of Regulators1Digi-Key
Operating Temperature Range-40°C ~ 85°CDigi-Key
Output ConfigurationPositiveDigi-Key
Output Current (Max)200mADigi-Key
Output TypeFixedDigi-Key
Output Voltage (Max)-Digi-Key
Output Voltage (Min)3.3VDigi-Key
Package CaseSC-74A, SOT-753Digi-Key
Protection FeaturesOver CurrentDigi-Key
Psrr73dB (1kHz)Digi-Key
Voltage Dropout (Max)0.2V @ 150mADigi-Key

When To Use

  1. 3.3V @ 200mA low-voltage logic rail: The fixed 3.3V output with a 200mA max current matches typical microcontroller and sensor power needs, while the low dropout voltage of 0.2V at 150mA ensures minimal headroom and heat dissipation. Using a general-purpose linear regulator without low dropout would cause excessive voltage drop and thermal stress under similar loads.

  2. Battery-powered system with 5.5V max input and long standby: The ultra-low quiescent current of 60µA extends battery life while the enable pin allows power gating. A synchronous buck controller, despite higher efficiency, would waste standby power due to higher IQ and switching losses, risking premature battery depletion.

  3. Industrial control with -40°C to 85°C operation: The specified temperature range covers most industrial environments without derating. A generic LDO regulator without guaranteed operation to -40°C risks latch-up or unpredictable output drift in cold start conditions.

When Not To Use

  1. Output current > 200mA required: The 200mA max output current rating disqualifies this part for higher loads. Use a multi-phase buck controller to distribute current and reduce thermal stress.

  2. Input voltage exceeds 5.5V max: This device’s 5.5V max input limits its application above 5.5V rails. Use a high-current synchronous buck with external FETs designed for higher input voltages and currents.

  3. Output noise critical with low dropout voltage: The fixed output and dropout voltage of 0.2V at 150mA may not meet sensitive analog rail requirements where noise and ripple must be minimal. Use an LDO regulator optimized for low noise and minimal dropout.

Application Notes

Gotchas

  1. [Startup under light load]: Assuming the device will start cleanly with near-zero output load can lead to output voltage undershoot or oscillation. The internal loop requires a minimum load to stabilize regulation.
    What happens: Output voltage dips below 3.3V briefly on startup, causing downstream logic resets or erratic behavior.
    Fix: Add a small bleed resistor or minimum load (~1mA) on the output to ensure stable startup.

  2. [ESR of output capacitor too low]: Using ultra-low ESR ceramic capacitors alone may cause loop instability not evident from the datasheet’s fixed output specs.
    What happens: Output exhibits high-frequency ringing and intermittent dropout under transient loads, visible on scope as oscillations.
    Fix: Add a small ESR tantalum or polymer capacitor in parallel or select a ceramic with recommended ESR range per application notes.

  3. [Input voltage transient spikes]: The 5.5V absolute max input rating excludes transient voltage spikes on the input line, which can occur during hot-plug or inductive load switching.
    What happens: Device latch-up or permanent damage occurs despite steady-state input below 5.5V, with partial or total loss of regulation.
    Fix: Include a transient voltage suppressor or input TVS diode and proper bulk capacitance to clamp voltage spikes safely.

  4. [PCB layout ground loops]: Routing ground return paths with high impedance or loops near switching nodes can induce noise coupling into the enable pin.
    What happens: Device randomly disables/enables under load changes, seen as intermittent output dropout without power cycling.
    Fix: Use star grounding for enable and analog grounds, separate from power return, and keep ground trace length minimal.