This part is a kind of semiconductor called G9091.

Function of this product has 300mA Low-Dropout Linear Regulators.

Manufacturers : Global Mixed-mode Technology

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Global Mixed-mode Technology Inc. G9091 300mA Low-Dropout Linear Regulators Features „ „ „ „ „ „ General Description The G9091 is a low supply current, low dropout linear regulator that comes in a space saving SOT-23-5, TSOT-23-5, SC-70-4(SC-82), SC-70-5, TDFN2X2-6 and TDFN2X2-8 package. The supply current at no-load is 100µA. In the shutdown mode, the maximum supply current is less than 1µA. The over-current protection limit is set at 430mA typical. An overtemperature protection circuit is built-in in the G9091 to prevent thermal overload. These power saving features make the G9091 ideal for use in the battery-powered applications such as notebook computers, cellular phones, and PDA’s. These devices feature a shutdown function and are offered in active low with auto discharge [ ... ]

G9091 PDF Datasheet Download