5V rail, 1.5A, PSRR 68 dB — the ACV variant
The L7805ACV is a 5 V fixed-output linear regulator from STMicroelectronics, rated for 1.5 A continuous output current in the TO-220-3 through-hole package. Its headline differentiator is the 68 dB PSRR at 120 Hz — 6 dB higher than the standard L7805CV — which matters when the unregulated input carries 100/120 Hz ripple from a rectifier-capacitor front end. That extra rejection keeps the 5 V rail cleaner for analog loads like op-amp supplies or ADC reference buffers without adding a post-filter. The part is a single positive regulator with over-temperature and short-circuit protection built in. Quiescent current is 6 mA typical, so the efficiency floor is set by the dropout voltage: 2 V max at 1 A. That means the input must stay above 7 V to hold regulation at full load — a 35 V absolute maximum input gives plenty of headroom for a 9 V or 12 V unregulated bus.
PSRR delta against the L7805CV and L7805ABV
The L7805ACV shares the same 1.5 A output, 2 V dropout, and 6 mA quiescent current as the L7805CV, but the PSRR is 68 dB vs 62 dB at 120 Hz — a 6 dB improvement that halves the ripple feedthrough. The L7805ABV matches the 68 dB PSRR and extends the temperature range to -40°C to 125°C, making it the choice for outdoor or cold-crank environments. If the BOM already specifies the ACV suffix, the PSRR advantage is the reason; if the operating ambient never drops below 0°C, the ACV saves cost over the ABV.