Fixed 0.8 V rail for low-voltage digital cores
The STMicroelectronics LDK130M08R is a fixed-output LDO regulator delivering 300 mA at 0.8 V from a 5.5 V maximum input rail. With a maximum dropout voltage of 0.4 V at full load, the input-to-output headroom needs to stay above 400 mV across the load range. A 5 V rail feeding this part has plenty of margin; a 1.2 V rail feeding it would not — the dropout spec sets the minimum input voltage at 1.2 V for a clean 0.8 V output.
55 dB PSRR — quiets the rail for analog and RF
The LDK130M08R holds 55 dB of power-supply rejection from 120 Hz through 10 kHz. That covers the fundamental and first few harmonics of a 100 kHz switching regulator — the LDO attenuates the ripple by a factor of ~560 before it reaches the load. For a noise-sensitive analog front-end or a radio transceiver sharing a board with a buck converter, this PSRR profile keeps the supply clean enough to avoid desense or ADC code spread. The 60 µA quiescent current means the regulator's own draw is negligible in battery-backed always-on domains — a microcontroller in sleep mode sees the LDO's consumption as a fraction of the total sleep budget.
The LDK130M08R carries AEC-Q100 qualification, the automotive IC stress test standard. Built-in over-current and over-temperature protection means the regulator shuts down before the die exceeds its safe operating area — a short on the output rail or a stalled fan load triggers the protection without cascading to the upstream supply.
SOT-23-5 footprint and enable-pin control
The part comes in a SOT-23-5 package (SC-74A body), a five-pin footprint with 0.95 mm pitch. The small outline suits space-constrained automotive ECU boards where every square millimeter counts. The enable pin allows the system microcontroller to power down the regulator during standby — pulling EN low drops the output and reduces the supply current to the microamp range. Surface-mount assembly with standard reflow profiles — no special handling beyond the usual MSL precautions for a small-outline package.
Active production — sourced to order
The part carries full material declaration and REACH compliance documentation from STMicroelectronics.
