Current fold-back is included, to 60mA for low-current mode and 110mA for high-current mode, to alleviates thermal shut-down cycling during short-circuit fault conditions, and to helps protect the IC from damage.
Thermal considerations are important because the chip comes in a small package – a 1.2 x 1.6mm X-DFN1612-8 (Type B) with an exposed thermal pad.
Operation is across 1.7 to 5.5V (6V abs max) and -40 to +85°C.
Output voltage is fixed, and there are variants at: 0.9, 1.0, 1.2, 1.5, 1.8, 2.5, 2.8, 3.0 and 3.3V.
Drop-out voltage varies between variants. The highest 1A max dropout voltage amongst these is 0.3V, but they are typically lower – the lowest typical drop-out is 60mV at 500mA. For the 3.3V version, max drop-out is 190mV.
1kHz 200mVp-p PSRR (power supply rejection ratio) is 80dB (Vout>1.8V, 30mA Vin=Vout+1V) or 75dB for <1.8V parts.
“The AP7368 is an ultra-low dropout linear regulator with high PSRR and is optimised for applications that require low-noise voltage rails while occupying only a small space,” according to the company.
No-load quiescent current is 110μAtyp (170µAmax), dropping to 500nA (3µAmax) when the enable pad is pulled to 0V – which also turns on an active output discharge circuit.