Fixed 1.2V rail for sensitive loads
The MCP1801T-1202I/OT is a fixed 1.2V LDO from Microchip's MCP1801 series, delivering up to 150 mA continuous output. The 1.2V fixed output means this is not an adjustable variant — confirm your BOM voltage matches before committing the line. The 50 µA quiescent current keeps the self-draw low in always-on domains like sensor bias or RTC keep-alive supplies.
PSRR and noise rejection at 10 kHz
A PSRR of 70 dB at 10 kHz means this LDO attenuates switching ripple from a DC-DC converter by a factor of about 3000 at that frequency. For a 1.2V rail feeding an analog front-end or a PLL supply, that rejection matters — the 10 kHz point is where many mid-frequency buck converters switch. Below 1 kHz the PSRR is typically higher; above 100 kHz it rolls off. If your upstream switcher runs at 2 MHz, the attenuation at that frequency will be lower — plan for a post-filter if the noise budget is tight.
Package, enable, and protection
Housed in a SOT-23-5 (SC-74A) package, the footprint is compact — 0.95 mm pitch, single-layer fan-out is feasible with 0.3 mm traces. The enable pin lets a GPIO or supervisor sequence the rail on/off, useful for power-sequencing schemes or putting the load into a low-power sleep state. Protection is limited to over-current; there is no thermal shutdown or reverse-voltage protection on this part. If the load can short or the input can be reversed, external protection is needed.