1.5 V fixed rail with 70 dB PSRR — what that buys you
The MIC5253-1.5YC5-TR is a 100 mA fixed-output LDO from Microchip's Teeny™ series, delivering 1.5 V from a maximum 5.5 V input with a dropout voltage of 0.3 V at full load. The headline spec is its power-supply rejection ratio: 70 dB at 1 kHz, tapering to 65 dB at 10 kHz. That means it attenuates switching-regulator ripple and digital noise on the input rail by a factor of roughly 3000 at 1 kHz — enough to keep a sensitive analog front-end or RF bias supply clean without a post-filter LC stage. This is a low-dropout part, not a zero-dropout one — budget the margin.
Package, temperature grade, and protection
Surface-mount assembly with standard reflow profiles; no exposed pad to solder. Built-in over-current, over-temperature, and under-voltage lockout (UVLO) protection means the regulator handles output shorts, thermal runaway, and brownout conditions without external supervisory circuitry. The enable pin lets a microcontroller or GPIO shut down the output, dropping quiescent current to near zero when the load is idle.
Quiescent current and supply budget
Quiescent current is 100 µA typical, with a maximum supply current of 150 µA. This is not an ultra-low-Iq LDO — a dedicated always-on battery rail would drain faster than with a 1 µA part — but for a rail that powers an active load drawing tens of milliamps, the 100 µA overhead is a rounding error in the system power budget. The trade-off is the PSRR figure: lower-Iq LDOs typically trade off rejection at higher frequencies.
It is ROHS3 compliant. Sourced to order against BOM quantities; availability and current pricing confirmed at RFQ through independent distribution channels.