Key Specs

SpecValueConditionSource
Control Features-Digi-Key
Current Quiescent IQ4 µADigi-Key
Input Voltage (Max)6VDigi-Key
Mounting TypeSurface MountDigi-Key
Number Of Regulators1Digi-Key
Operating Temperature Range-40°C ~ 125°CDigi-Key
Output ConfigurationPositiveDigi-Key
Output Current (Max)250mADigi-Key
Output TypeFixedDigi-Key
Output Voltage (Max)-Digi-Key
Output Voltage (Min)3.5VDigi-Key
Package CaseTO-243AADigi-Key
Protection FeaturesOver Current, Over Temperature, Short CircuitDigi-Key
Psrr44dB (100Hz)Digi-Key
Supplier Device PackageSOT-89-3Digi-Key
Voltage Dropout (Max)0.35V @ 250mADigi-Key

When To Use

Use the MCP1700T-3502E/MB in low-power, battery-operated devices requiring a fixed 3.5V output voltage with a maximum output current of 250mA. Its low quiescent current of 4 µA makes it ideal for portable and handheld electronics where power efficiency is critical. Applications such as sensor modules, IoT devices, and small microcontroller power supplies benefit from its low dropout voltage of 0.35V at full load and its wide operating temperature range of -40°C to 125°C.

When Not To Use

Do not use the MCP1700T-3502E/MB in applications requiring output voltages other than 3.5V fixed or output currents exceeding 250mA. For example, high-current motor drivers or high-voltage power supplies are unsuitable due to the limited maximum input voltage of 6V and maximum output current of 250mA. In such cases, use adjustable regulators or higher current LDOs designed for those requirements.

Application Notes

The input pin is the switching node where voltage transitions occur; keep the loop area between the input capacitor (if used) and the regulator input pin as small as possible to minimize noise and improve stability. The output pin is noise-sensitive and should be routed away from high-frequency switching nodes to reduce interference. Although the MCP1700T-3502E/MB has built-in protection features including over temperature, a heatsink or adequate PCB copper area is recommended when operating near the maximum output current of 250mA with a high input voltage close to 6V to maintain junction temperature within safe limits.

Gotchas

  1. Mistake: Supplying an input voltage above the maximum rating of 6V.
    Failure Mode: Device damage or permanent degradation due to overstress.
    Fix: Ensure the input voltage never exceeds 6V by design or with protective circuitry.

  2. Mistake: Operating the regulator at output currents exceeding 250mA.
    Failure Mode: Excessive dropout voltage, thermal shutdown, or regulator failure due to overcurrent conditions.
    Fix: Limit the load current to 250mA maximum or select a regulator with higher current capability.

  3. Mistake: Ignoring thermal dissipation requirements at high load and input voltage.
    Failure Mode: Over temperature protection triggers, causing intermittent shutdown or reduced reliability.
    Fix: Evaluate power dissipation (Vin - Vout) × Iout and ensure proper PCB thermal design; consider thermal vias or copper area to dissipate heat.