1.25V fixed output, 200mA — SOT-753 footprint
The ROHM BU1CTD3WG-TR is a fixed-output linear regulator delivering 1.25V at up to 200mA from a maximum 6V input rail. The SOT-753 (SC-74A) package is a five-pin SSOP with a 0.95mm pitch — hand-solderable with a fine tip and a steady hand, and the small footprint leaves room on a tight board for decoupling caps. Quiescent current sits at 60µA typical, so the regulator's own draw won't drain a battery overnight in always-on or sleep-mode circuits. The enable pin lets a microcontroller or a GPIO pull the output high-Z, cutting Iq further when the load is idle.
70dB PSRR at 1kHz — clean rail for sensitive analog
With 70dB of power-supply rejection at 1kHz, this LDO attenuates switching ripple from a buck converter or SMPS by a factor of about 3000 — enough to keep a 10mVpp input ripple down to roughly 3µVpp at the output. That matters when the regulator feeds an op-amp front-end or an ADC reference that cannot tolerate supply hash. Maximum dropout voltage is 0.9V at the full 200mA load. The dropout is specified at the full load, so at lighter currents the headroom requirement relaxes. Protection includes over-current and over-temperature shutdown — the regulator folds back or turns off before a shorted output or a hot bench damages the die.