LP8774x Three Buck Converters and 5-V Boost for IWR Radar Sensors

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.

Package Information

PART

NUMBER(1)

PACKAGE

PACKAGE

SIZE(2)

BODY SIZE

(NOM)

LP8774x

RXV (VQFN-

HR, 28)

4.50 mm ×

5.00 mm

4.50 mm ×

5.00 mm

(1)

For all available packages, see the orderable addendum at

the end of the data sheet.

(2)

The package size (length × width) is a nominal value and

includes pins, where applicable.

SW_B1

PVIN_B1

PVIN_B2

VCCA

VIN

FB_B1

VOUT1

LOAD

CS_SPI/WD_DIS

SCK_SPI

nINT

SYNCCLKIN

GNDs

ENABLE

SW_B2

FB_B2

VOUT2

VMON1/GPO1

nERR/GPO2

SW_BST

VOUT_BST

VOUT4

LOAD

LOAD

SW_B3

FB_B3

VOUT3

LOAD

PVIN_B3

SDO_SPI

SDI_SPI

nRSTOUT

VOUT_VLDO

SPI interface

VIO_LDO

VOUT5

Simplified Application

LP87745

SNVSCH5 – NOVEMBER 2023

An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.