Ricoh Electronic Devices Company RP122Z Series LDO Regulators, available now from Mouser, give 90dB ripple rejection and fast transient response speed, with just 9.5µA current consumption without output load. The regulators also produce a low 8µVRMS noise level at the output voltage. These characteristics make these devices excellent for battery-powered devices with noise-sensitive circuits, including smartphones, tablets, and RF modules. The regulators contribute to lower the entire supply current of the device and improve the lifetime of the battery, which also excludes the necessity to switch between operating modes since the LDO adjusts seamlessly to the output current demand.
The LDO regulators combine several protection features. A fold-back current limit circuit reduces the output current to approximately 70mA in case of a short circuit, shielding the LDO and other electronic parts of the application from damage. Thermal protection shuts the LDO down when the junction temperature rises above 165C. An inrush current limit circuit stops any output overshoot and undershoot throughout the start-up period. The inrush period is internally fixed with a maximum of 700µs.
The device has an optional auto-discharge function. This feature quickly discharges the output capacitor once the IC is set to the standby mode. To improve stable operation, a small ceramic capacitor with a low ESR value and a minimum of 1µF can be employed.
The LDO regulator is provided in a compact WLCSP-4-P8 package and is RoHS compliant and halogen-free.