GXSC LDO chip replaces ADM7172 for application in phase-locked loop/voltage controlled oscillator (PLL/VCO)

In high-end electronic systems such as communication, radar, and precision measurement, phase-locked loops (PLL) and voltage controlled oscillators (VCO) are modules that achieve signal synchronization and frequency synthesis. The quality of power supply is one of the factors that affect the performance of PLL/VCO. This article mainly introduces the application of a GXSC low dropout linear regulator LDO chip replacing ADM7172 in phase-locked loops/voltage controlled oscillators. This regulator is designed for high-performance analog and mixed signal circuit power supply and can PIN TO PIN replace ADM7172.

The GXSC CMOS low dropout linear regulator adopts an advanced proprietary architecture with high power suppression and low noise characteristics. Excellent line and load transient response can be achieved through 22uF ceramic output capacitor regulation. This feature can effectively avoid power supply noise coupling into the control loop and oscillation circuit of the VCO, significantly reducing the phase noise of the VCO output signal, ensuring that the PLL can stably lock the frequency, and improving the signal purity of the system.

The working voltage of the device is 2.3V to 6.5V, with an output current of up to 2A. This product is very suitable for high-performance analog and mixed signal circuits that adjust the working voltage range from 6V to 1.2V. And it provides 17 fixed output voltage options. The available voltage options in stock include ADJ adjustable outputs of 1.3V, 1.8V, 2.5V, 3.0V, 3.3V, 4.2V, and 5.0V.

Advantages of the GXSC voltage regulator product:

• Input voltage range: 2.3~6.5V

• Maximum load current: 2A

• Low noise: 5uVrms@100Hz ~100kHz

Fast transient response: 10 μ s @ 1mA to 1A

The PSRR at 100kHz load step is 60dB

Low pressure drop: 230 mV@2A Load, VOUT=3V

Adopting plastic sealed DFN8, compatible with imported product ADM7172