control logic

Soft

start

Thermal

Shtdwn

UVLO

PG control

power

control

error

amplifier

gate

drive

HS lim

LS lim

PVIN

PVIN

AVIN

PG

PGND

PGND

AGND

comp

comp

+

_

DCS - Control

TM

direct control

&

compensation

comparator

ramp

SW

SW

SW

EN

*

SS/TR

DEF

*

FSW

*

VOS

FB

*

(see Detailed Description section).

TPS62152-Q1

www.ti.com

SLVSC52B – JULY 2013 – REVISED SEPTEMBER 2015

7 Detailed Description

7.1 Overview

The base for the TPS62152-Q1 synchronous switched-mode power converters is the DCS-Control™ topology

(direct control with seamless transition into power-save mode), an advanced regulation topology that combines

the advantages of hysteretic, voltage-mode and current mode control including an ac loop directly associated to

the output voltage. This control loop takes information about output voltage changes and feeds it directly to a fast

comparator stage. The control loop sets the switching frequency, which is constant for steady-state operating

conditions, and provides immediate response to dynamic load changes. A voltage feedback loop obtains

accurate dc load regulation. The internally compensated regulation network achieves fast and stable operation

with small external components and low-ESR capacitors.

The DCS-Control topology supports pulse-width modulation (PWM) mode for medium and heavy load conditions

and a power save-mode at light loads. During PWM, the device operates at the nominal switching frequency in

continuous-conduction mode. This frequency is typically about 2.5 MHz, with a controlled frequency variation

depending on the input voltage. If the load current decreases, the converter enters power-save mode to sustain

high efficiency down to very light loads. In power-save mode, the switching frequency decreases linearly with the

load current. Because DCS-Control topology supports both operation modes within one single building block, the

transition from PWM to power-save mode is seamless, without effects on the output voltage.

Because the TPS62152-Q1 device has a fixed output voltage of 3.3 V, the device provide smallest solution size

and lowest current consumption, requiring only three external components. An internal current limit supports

nominal output currents of up to 1 A.

The TPS62152-Q1 device offers both excellent dc voltage and superior load-transient regulation, combined with

very low output-voltage ripple, minimizing interference with RF circuits.

7.2 Functional Block Diagram

Copyright © 2013–2015, Texas Instruments Incorporated

Submit Documentation Feedback

11

Product Folder Links: TPS62152-Q1