Fixed 10V rail for industrial analog supplies
The MCP1804T-A002I/DB is a single-output, fixed 10V positive LDO regulator from Microchip Technology, rated for 150 mA continuous output.
At full 150 mA the actual dropout will be higher, so budget headroom accordingly. PSRR is 50 dB at 1 kHz — this attenuates ripple from a switching pre-regulator by a factor of about 316. For a 100 mVpp ripple at 1 kHz, the output sees roughly 0.3 mVpp. At higher frequencies PSRR rolls off, so post-filtering is needed if the upstream switcher runs above 100 kHz. Quiescent current is 105 µA typical, with a maximum supply current of 125 µA. In always-on or battery-backed applications, this self-consumption is low enough to avoid significant drain — a 100 mAh coin cell would last over 800 hours at Iq alone.
Package and board-fit — SOT-223-3
Housed in the TO-261-4 (SOT-223-3) package, the part has an exposed thermal pad on the tab — the datasheet's copper-area recommendation governs the power dissipation. For 150 mA at 10 Vout with a 12 Vin, the dropout is small but the pass element still dissipates (Vin - Vout) × Iout = 0.3 W; a 1-inch² copper pour keeps the junction rise under 30°C in still air.
