The HT75xx-1 series is a set of three-terminal low power high voltage implemented in CMOS technology. They can deliver 100mA output current and allow an input voltage as high as 30V. They are available with several fixed output voltages ranging from 2.1V to 12.0V. CMOS technology ensures low voltage drop and low quiescent current. Although designed primarily as fixed voltage regulators, these devices can be used with external components to obtain variable voltages and currents. BRAND HOLTEK DATASHEET

The HT9170D is a Dual Tone Multi Frequency (DTMF) receivers integrated with digital decoder and bandsplit filter functions as well as power-down mode and inhibit mode operations. Such devices use digital counting techniques to detect and decode all the 16 DTMF tone pairs into a 4-bit code output. BRAND:- HOLTEK Datasheet:HT9170D Datasheet

The IL1117C is a series of low dropout voltage regulators which can provide up to 1A of output current. The IL1117C is available in eight fixed voltage, 1.2, 1.25, 1.5, 1.8, 2.5, 2.85, 3.3 and 5.0V. BRAND - IK SEMICON PACKAGE - SOT223 DATASHEET