TPSM8291x 3-V to 17-V, 2-A/3-A Low-Noise and Low-Ripple Buck Power Module with

Integrated Ferrite Bead Filter Compensation

1 Features

• Low output noise < 20 µVRMS

(100 Hz to 100 kHz)

• Low output voltage ripple < 10 µVRMS after ferrite

bead

• High PSRR of > 65 dB (up to 100 kHz)

• 2.2-MHz or 1-MHz fixed frequency peak current

mode control

• Synchronizable with external clock (optional)

• Integrated loop compensation supports ferrite

bead for second stage L-C filter with 30-dB

attenuation (optional)

• Spread spectrum modulation (optional)

• 3.0-V to 17-V input voltage range

• 0.8-V to 5.5-V output voltage range

• 57-mΩ/20-mΩ RDSon

• Output voltage accuracy of ±1%

• Precise enable input allows

– User-defined undervoltage lockout

– Exact sequencing

• Adjustable soft start

• Power-good output

• Output discharge (optional)

• –40°C to 125°C junction temperature range

– –55°C to 125°C for -ET versions

• Create a custom design using the TPSM8291x

with the WEBENCH® Power Designer

2 Applications

• Telecom infrastructure

• Test and measurement

• Aerospace and defense (radar, avionics)

• Medical

3 Description

The TPSM8291x devices are a family of high-

efficiency, low-noise and low-ripple current mode

synchronous buck power modules. The devices are

ideal for noise sensitive applications that would

normally use an LDO for post regulation such as

high-speed ADCs, clock and jitter cleaner, serializer,

de-serializer, and radar applications.

The devices operate at a fixed switching frequency of

2.2 MHz or 1 MHz and can be synchronized to an

external clock.

To further reduce the output voltage ripple, the device

integrates loop compensation to operate with an

optional second-stage ferrite bead L-C filter. This

feature allows an output voltage ripple below 10

µVRMS.

Low-frequency noise levels, similar to a low-noise

LDO, are achieved by filtering the internal voltage

reference with an integrated capacitor on the NR/SS

pin. An external capacitor can be added to the module

for additional filtering.

The optional spread spectrum modulation scheme

spreads the DC/DC switching frequency over a wider

span, which lowers the mixing spurs.

Device Information

DEVICE NAME

OUTPUT

CURRENT

PACKAGE

(1)

BODY SIZE

(NOM)

TPSM82912

(2),

TPSM82912-ET

(2)

2 A

RDU (QFN,

28)

4.50 mm × 5.50

mm × 1.80 mm

TPSM82913,

TPSM82913-ET

(2)

3 A

(1)

For all available packages, see the orderable addendum at

the end of the data sheet.

(2)

Product preview.

Frequency (Hz)

1x101

1x102

1x103

1x104

1x105

1x1063x106

0.0005

0.001

0.002

0.005

0.01

0.02

0.05

0.1

0.2

0.5

1

2

5

10

CNRSS = open, 19.6 VRMS

CNRSS = 220 nF, 17 VRMS

CNRSS = 470 nF, 16.6 VRMS

CNRSS = 2.2 F, 16.3 VRMS

Output Noise Versus Frequency

Vout

3.3 V / 3 A

Vin

12 V

VIN

EN/SYNC

S-CONF

CIN

10 µF

3x

22 µF

FB

PG

NR/SS

OUT

4.87 k

15.4 k

22 µF

PGND

10 nH

Typical Application

TPSM82913

SLVSGJ4A – OCTOBER 2022 – REVISED DECEMBER 2022

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. UNLESS OTHERWISE NOTED, this document contains PRODUCTION

DATA.