The ZXTR2012Z-7 is a fixed 12 V linear regulator, but its 100 V max input means it can sit directly on a 24 V truck battery, a 48 V telecom bus, or an automotive 12 V rail that sees 60 V load-dump transients — no external pre-regulator needed. That wide input range is the main reason you'd pick this over a garden-variety 30 V LDO. With a 47 mA output ceiling, it's not a main-rail regulator. It's sized for the keep-alive supply on a CAN transceiver, the bias rail for a gate driver, or the always-on 12 V feed for a sensor module — loads that draw tens of milliamps but need the transient immunity a high-voltage front end provides.
AEC-Q101 — what the automotive grade buys you
The ZXTR2012Z-7 is qualified to AEC-Q101, the automotive discrete semiconductor stress test. That covers -40°C to 125°C operation, temperature cycling, and ESD robustness — the kind of reliability a powertrain ECU or under-hood module demands. The scorch mark on a failed board is rarely on a part that passed AEC-Q101; it's the unqualified part next to it. Lifecycle status is Active, ROHS3 compliant.
PSRR and quiescent — the fine print
PSRR is 45 dB at 100 Hz — that's modest by modern LDO standards. If your 12 V rail carries heavy 100/120 Hz ripple from a rectified AC source or a switching pre-regulator, the output will show about 1/180th of that ripple. For a sensor bias rail that feeds an ADC, you may want more rejection; for a relay driver or a logic supply, 45 dB is fine. Quiescent current is 400 µA typical, max supply current 900 µA. That's not a micropower part — it won't starve a battery in sleep, but it's not in the 1 µA class. The 400 µA Iq is the price you pay for the 100 V input capability and the automotive temp range.
Package and board fit — SOT-89-3
Supplied in the SOT-89-3 package, also known as TO-243AA. The centre tab is the output (Vout) — it carries the 47 mA load plus the die heat. The tab's copper area on the PCB sets the thermal resistance; for 47 mA at 12 V with a 24 V input, the dissipation is about 0.56 W, which the SOT-89 can handle with a modest pad.