LP87745中文資料德州儀器數據手冊PDF規(guī)格書

1 Features

? Device operating temperature : –40°C to +125°C

ambient

? Input voltage: 3.3 V nominal (3 V to 4 V range)

? Three low-noise step-down DC/DC converters:

– Output voltage: 0.9 V to 1.9 V, 0.8 V (BUCK3),

0.82 V (BUCK3)

– Maximum output current: 3 A/ 3 A/ 3 A

– Switching frequency: 4.4 MHz, 8.8 MHz, and

17.6 MHz

? 5 V boost converter

– Maximum output current: 350 mA

? 150 mA LDO

– Output voltage 1.8 V or 3.3 V

? Output short-circuit and overload protection

? Input overvoltage protection (OVP) and

undervoltage lockout (UVLO)

? Overtemperature warning and protection

? Serial peripheral interface (SPI)

2 Applications

? Factory automation & control

? Industrial transport (non-car & non-light truck)

? Low ripple, low noise applications

3 Description

The LP8774x device is designed to meet the power

management requirements of the IWR MMICs in

various industrial radar applications. The device has

three step-down DC/DC converters, a 5-V boost

converter and a 1.8 V or 3.3 V LDO. The LDO is

powered from the boost and intended for xWR I/O

supply. An SPI serial interface and enable signals

control the device.

The step-down DC/DC converters support

programmable switching frequency of 4.4 MHz, 8.8

MHz, or 17.6 MHz. High switching frequency and low

noise across wide frequency range enable LDO-free

power solution with minimal or no passive filtering.

The high switching frequency improves thermals and

transient settling for the MMIC RF rails. The device

forces the switching clock into PWM mode for optimal

RF performance and can also be synchronized to an

external clock. The device supports remote voltage

sensing to compensate IR drop between the regulator

output and the point-of-load (POL) which improves the

accuracy of the output voltage.