TPS62740 [TI]

具有 360nA Iq 的 2.2V 至 5.5V 输入、超低功耗 300mA 降压直流/直流转换器;


型号：	TPS62740
厂家：	TEXAS INSTRUMENTS
描述：	具有 360nA Iq 的 2.2V 至 5.5V 输入、超低功耗 300mA 降压直流/直流转换器转换器
文件：	总33页 (文件大小：3023K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

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TPS62740, TPS62742

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

TPS6274x 针对低功耗应用的 360nA I_Q降压转换器

1 特性

3 说明

•

输入电压 (V_IN) 范围：2.2V 至 5.5V

TPS6274x 是业界第一款降压转换器，此转换器特有典

型值为 360nA 的静态电流，并且搭配微型 2.2µH 电感

和 10µF 输出电容一起工作。这款基于 DCS-

典型值360nA 静态电流

10µA 输出电流时的效率高达 90%

Control™ 的全新器件将轻负载效率范围扩展至 10µA

负载电流以下。 TPS62740 支持高达 300mA 的输出

电流，TPS62742 支持高达 400mA 的输出电流。此

器件由可再充电锂离子电池，锂化学电池（例如锂亚硫

酰氯 (Li-SOC12)，锂锰电池 (Li-MnO2) 和两节或三节

碱性电池）供电运行。输入电压范围高达 5.5V，也实

现由 1 个 USB 端口和薄膜太阳能模块供电运行。用

户可使用 4 个 VSEL 引脚在 1.8V 至 3.3V 范围内选择

输出电压（步长 100mV）。 TPS6274x 搭配使用小型

输出电容，特有低输出纹波电压和低噪声。一旦电池

电压接近输出电压（接近 100% 占空比），此器件进

入无纹波 100% 模式运行，以防止输出纹波电压的增

加。然后，此器件停止开关，并且输出被连接至输入

电压。集成转换率受控负载开关特有典型值为 0.6Ω

的导通电阻，并且将选择的输出电压分配至临时使用的

子系统。 TPS6274 采用小型 12 引脚 2mm x 3mm²

WSON 封装，并且支持 31mm²的总体解决方案尺

寸。

高达 300mA/400mA 的输出电流

(TPS62740/TPS62742)

•

射频 (RF) 友好型 DCS-Control^TM

高达 2MHz 的开关频率

低输出纹波电压

1.8V 至 3.3V 之间 16 个可选输出电压（步长

100mV）

•

自动转换至无纹波 100% 模式

转换率受控的负载开关

VOUT / LOAD 上的放电功能

电源正常输出

针对与微型 2.2µH 电感器和 10µF C_OUT的共同运

行进行了优化

总体解决方案尺寸 < 31mm²

小型 2mm x 3mm²晶圆级小外形无引线 (WSON)

封装

•

2 应用范围

•

Bluetooth^®低功耗 (Low Energy)，消费类电子产品

用射频 (RF4CE)，短距离低功耗通信技术 (Zigbee)

器件信息⁽¹⁾

•

工业用仪表计量

能量采集

器件型号

TPS62740

TPS62742

封装

封装尺寸（标称值）

WSON

3.00mm x 2.00mm

(1) 要了解所有可用封装，请见数据表末尾的可订购产品附录。

4 典型应用

V_IN

2.2V - 5.5V

100

2.1V

Main rail

TPS62740

L 2.2mH

New

TPS62740

V_CC

VIN

C_OUT

C_IN

VOUT

10mF

VSEL1

VSEL2

VSEL3

VSEL4

GND

R_{pull up}

TPS62740 extends

light load efficiency range

down to 10mA output current

CTRL

LOAD

Switched

supply rail

Current

DCS-Control^TMtopology

Subsystem

(Sensors)

V_IN= 3.6V

V_OUT= 3.3V

0.001

0.01

0.1

Output Current (mA)

100

1000

PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not necessarily include testing of all parameters.

English Data Sheet: SLVSB02

TPS62740, TPS62742

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

www.ti.com.cn

9.3 Feature Description................................................... 8

9.4 Device Functional Modes........................................ 10

10 Application and Implementation........................ 12

10.1 Application Information.......................................... 12

10.2 Typical Application ............................................... 12

10.3 System Example ................................................... 22

11 Power Supply Recommendations ..................... 23

12 Layout................................................................... 23

12.1 Layout Guidelines ................................................. 23

12.2 Layout Example .................................................... 23

13 器件和文档支持 ..................................................... 24

13.1 器件支持 ............................................................... 24

13.2 文档支持 ............................................................... 24

13.3 相关链接................................................................ 24

13.4 商标....................................................................... 24

13.5 静电放电警告......................................................... 24

13.6 术语表 ................................................................... 24

14 机械封装和可订购信息 .......................................... 24

特性.......................................................................... 1

应用范围................................................................... 1

说明.......................................................................... 1

典型应用................................................................... 1

修订历史记录 ........................................................... 2

Device Comparison Table..................................... 3

Pin Configuration and Functions......................... 3

Specifications......................................................... 4

8.1 Absolute Maximum Ratings ...................................... 4

8.2 Handling Ratings ...................................................... 4

8.3 Recommended Operating Conditions....................... 5

8.4 Thermal Information ................................................. 5

8.5 Electrical Characteristics........................................... 5

8.6 Typical Characteristics.............................................. 7

Detailed Description .............................................. 8

9.1 Overview ................................................................... 8

9.2 Functional Block Diagram ......................................... 8

5 修订历史记录

NOTE: Page numbers for previous revisions may differ from page numbers in the current version.

Changes from Revision A (November 2013) to Revision B

Page

•

已添加 TPS62742 器件........................................................................................................................................................... 1

Added efficiency graph, Figure 11........................................................................................................................................ 15

TPS62740, TPS62742

www.ti.com.cn

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

6 Device Comparison Table

PACKAGE

MARKING

OUTPUT CURRENT

[mA]

T_A

PART NUMBER

TPS62740

TPS62741⁽¹⁾

OUTPUT VOLTAGE SETTING VSEL 1 - 4

1.8V to 3.3V in 100mV steps

1.3V to 2.8V in 100mV steps

1.8V to 3.3V in 100mV steps

300mA

400mA

62740

-/-

–40°C to 85°C

TPS62742

62742

(1) Device option, contact TI for more details

7 Pin Configuration and Functions

WSON PACKAGE

12-Pin

DSS PACKAGE

(TOP VIEW)

VIN

GND

VSEL1

VSEL2

VSEL3

VSEL4

CTRL

VOUT

LOAD

Pin Functions

I/O

DESCRIPTION

NAME

VIN

PWR V_INpower supply pin. Connect this pin close to the VIN terminal of the input capacitor. A ceramic capacitor

of 4.7µF is required.

OUT

This is the switch pin and is connected to the internal MOSFET switches. Connect the inductor to this

terminal.

GND

PWR GND supply pin. Connect this pin close to the GND terminal of the input and output capacitor.

CTRL

This pin controls the output LOAD pin. With CTRL = low, the output LOAD is disabled. This pin must be

terminated.

VOUT

LOAD

Feedback pin for the internal feedback divider network and regulation loop. An internal load switch is

connected between this pin and the LOAD pin. Connect this pin directly to the output capacitor with a short

trace.

OUT

This output is controlled by the CTRL Pin. With CTRL high, an internal load switch connects the LOAD pin

to the VOUT pin. The LOAD pin allows to connect / disconnect other system components to the output of

the DC/DC converter. This pin is pulled to GND with CTRL pin = low. The LOAD pin features a soft

switching. If not used, leave the pin open.

Power good open drain output. This pin is high impedance to indicate "Power Good". Connect a external

pull up resistor to generate a "high" level. If not used, this pin can be left open.

VSEL4

VSEL3

VSEL2

VSEL1

Output voltage selection pins. See Table 1 for V_OUTselection. These pins must be terminated and can be

changed during operation.

High level enables the devices, low level turns the device into shutdown mode. This pin must be

terminated.

EXPOSED

THERMAL PAD

Not electrically connected to the IC, but must be soldered. Connect this pad to GND and use it as a central

GND plane.

TPS62740, TPS62742

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

www.ti.com.cn

Table 1. Output Voltage Setting

Device

VOUT

1.8

1.9

2.0

2.1

2.2

2.3

2.4

2.5

2.6

2.7

2.8

2.9

3.0

3.1

3.2

3.3

VSEL 4

VSEL 3

VSEL 2

VSEL 1

TPS62740 / 42

8 Specifications

8.1 Absolute Maximum Ratings⁽¹⁾

Over operating free-air temperature range (unless otherwise noted)

MIN

–0.3

MAX

UNIT

VIN

(3)

V_IN+0.3V

3.7

Pin voltage⁽²⁾

PG pin

EN, CTRL, VSEL1-4

VOUT, LOAD

I_PG

sink current

°C

Maximum operating junction temperature, T_J

–40

150

(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings

only and functional operation of the device at these or any other conditions beyond those indicated under recommended operating

conditions is not implied. Exposure to absolute–maximum–rated conditions for extended periods may affect device reliability.

(2) All voltage values are with respect to network ground terminal GND.

(3) The MAX value V_IN+0.3V applies for applicative operation (device switching), DC voltage applied to this pin may not exceed 4V

8.2 Handling Ratings

MIN

MAX

150

UNIT

T_stg

Storage temperature range

–65

°C

Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all

pins⁽¹⁾

2000

V_(ESD)

Electrostatic discharge

Charged device model (CDM), per JEDEC specification

JESD22-C101, all pins⁽²⁾

1000

(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. The human body

model is a 100-pF capacitor discharged through a 1.5-kΩ resistor into each pin.

(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

TPS62740, TPS62742

www.ti.com.cn

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

8.3 Recommended Operating Conditions

MIN NOM MAX UNIT

(1)

V_IN

Supply voltage V_IN

2.2

1.5

5.5

300

400

100

V_OUTnom+ 0.7V ≤ V_IN≤ 5.5V

3V ≤ V_IN, V_OUTnom+ 0.7V ≤ V_IN≤ 5.5V TPS62742

_OUTnom≤ V_IN≤ V_OUTnom+0.7V

TPS62740

I_OUT

I _LOAD

Device output current (sum of I_OUTand I _LOAD

)

I_LOADLoad current (current from LOAD pin)

Inductance

2.2

3.3 µH

C_OUTOutput capacitance connected to VOUT pin (not including LOAD pin)

C_LOADCapacitance connected to LOAD pin

µF

T_J

Operating junction temperature range

Ambient temperature range

-40

125

°C

T_A

(1) The minimum required supply voltage for startup is 2.15V (undervoltage lockout threshold V_{TH_UVLO+}) . The device is functional down to

2V supply voltage (falling undervoltage lockout threshold V_{TH_UVLO-}).

8.4 Thermal Information

THERMAL METRIC

DSS / 12 PINS

UNIT

R_θJA

Junction-to-ambient thermal resistance

61.8

70.9

25.7

1.9

R_θJCtop

R_θJB

Junction-to-case (top) thermal resistance

Junction-to-board thermal resistance

°C/W

ψ_JT

Junction-to-top characterization parameter

Junction-to-board characterization parameter

Junction-to-case (bottom) thermal resistance

ψ_JB

25.7

7.2

R_θJCbot

8.5 Electrical Characteristics

V_IN= 3.6V, T_A= –40°C to 85°C typical values are at T_A= 25°C (unless otherwise noted)

PARAMETER

TEST CONDITIONS

MIN

TYP MAX

UNIT

SUPPLY

V_IN

Input voltage

2.2

5.5

range

EN = V_IN, CTRL = GND, I_OUT= 0µA, V_OUT= 1.8V, device not switching,

EN = V_IN, I_OUT= 0mA, CTRL = GND, V_OUT= 1.8V , device switching

EN = V_IN, I_OUT= 0mA., CTRL = V_IN,V_OUT= 1.8V, device not switching

EN = GND, shutdown current into V_IN

360 1800

460

µA

Operating

quiescent current

I_Q

12.5

I_SD

Shutdown current

70 1000

EN = GND, shutdown current into V_IN, T_A= 60°C

Rising V_IN

150

2.075

1.925

450

2.15

V_{TH_UVLO+}

V_{TH_UVLO-}

Undervoltage

lockout threshold

Falling V_IN

INPUTS EN, CTRL, VSEL 1-4

V_{IH TH}

V_{IL TH}

I_IN

High level input

threshold

2.2V ≤ V_IN≤ 5.5V

1.1

Low level input

threshold

0.4

Input bias Current T_A= 25°C

T_A= –40°C to 85°C

POWER SWITCHES

High side

MOSFET on-

resistance

0.6

0.85

0.5

R_DS(ON)

V_IN= 3.6V, I_OUT= 50mA

Ω

Low Side

MOSFET on-

resistance

0.36

TPS62740, TPS62742

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

www.ti.com.cn

Electrical Characteristics (continued)

V_IN= 3.6V, T_A= –40°C to 85°C typical values are at T_A= 25°C (unless otherwise noted)

PARAMETER

TEST CONDITIONS

MIN

TYP MAX

UNIT

High side

MOSFET switch

current limit

2.2V ≤ V_IN≤ 5.5V, TPS62740

480

600

650

720

740

3.0V ≤ V_IN≤ 5.5V, TPS62742

590

I_LIMF

TPS62740

TPS62742

600

650

Low side MOSFET

switch current limit

OUTPUT DISCHARGE SWITCH (VOUT)

MOSFET on-

R_{DSCH_VOUT}

resistance

V_IN= 3.6V, EN = GND, I_OUT= -10mA into VOUT pin

Ω

Bias current into

VOUT pin

T_A= 25°C

T_A= –40°C to 85°C

100

V_IN= 3.6V, EN = V_IN, VOUT = 2V, CTRL =

GND

I_{IN_VOUT}

1010

LOAD OUTPUT (LOAD)

High side

0.6

1.25

Ω

R_LOAD

MOSFET on-

resistance

I_LOAD= 50mA, CTRL = V_IN, VOUT = 2.0V, 2.2 V ≤ V_IN≤ 5.5V

CTRL = GND, 2.2V ≤ V_IN≤ 5.5V, I_LOAD= - 10mA

Low side MOSFET

on-resistance

R_{DSCH_LOAD}

t_{Rise_LOAD}

V_LOADrise time

Starting with CTRL low to high transition, time to ramp V_LOADfrom 0V

to 95% VOUT = 1.8V, 2.2V ≤ V_IN≤ 5.5V, I_LOAD= 1mA

315

800

µs

AUTO 100% MODE TRANSITION

Auto 100% Mode

170

110

250

200

340

280

Rising V_IN,100% Mode is left with V_IN= V_OUT+ V_{TH_100+}, max value at

T_J= 85°C

V_{TH_100+}

leave detection

threshold

(1)

Auto 100% Mode

enter detection

threshold

Falling V_IN, 100% Mode is entered with V_IN= V_OUT+ V_{TH_100-}, max

value at T_J= 85°C

V_{TH_100-}

(1)

POWER GOOD OUTPUT (PG, OPEN DRAIN)

V_{TH_PG+}

V_{PG_Hys}

Power good

threshold voltage

Rising output voltage on VOUT pin, referred to V_VOUT

Hysteresis

97.5%

-3%

Low level output

voltage

2.2V ≤ V_IN≤ 5.5V, EN = GND, current into PG pin I_PG= 4mA

0.3

V_OL

I_{IN_PG}

Bias current into

PG pin

PG pin is high impedance, VOUT = 2V, EN =

V_IN, CTRL = GND, I_OUT= 0mA

T_A= 25°C

T_A= –40°C to 85°C

OUTPUT

t_ONmin

Minimum ON time V_IN= 3.6V, V_OUT= 2.0V, I_OUT= 0 mA

Minimum OFF time V_IN= 2.3V

225

t_OFFmin

t_{Startup_delay}

Regulator start up V_IN= 3.6V, from transition EN = low to high until device starts switching

delay time

t_Softstart

Softstart time with 2.2V ≤ V_IN≤ 5.5V, EN = V_IN

700 1200

µs

reduced switch

current limit

I_{LIM_softstart}

High side

MOSFET switch

current limit

Reduced switch current limit during softstart

TPS62740

TPS62742

150

200

Low side MOSFET

switch current limit

150

Output voltage

range

Output voltages are selected with pins VSEL 1 - 4

1.8

3.3

V_IN= 3.6V, I_OUT= 10mA, V_OUT= 1.8V

V_IN= 3.6V, I_OUT= 100mA, V_OUT= 1.8V

-2.5

–2

2.5

Output voltage

accuracy

V_VOUT

DC output voltage V_OUT= 1.8V, V_IN= 3.6V, CTRL = V_IN

load regulation

0.001

%/mA

%/V

DC output voltage V_OUT= 1.8V, CTRL = V_IN, I_OUT= 10 mA, 2.5V ≤ V_IN≤ 5.5V

line regulation

(1) V_INis compared to the programmed output voltage (V_OUT). When V_IN–V_OUTfalls below V_{TH_100-}the device enters 100% Mode by turning

the high side MOSFET on. The 100% Mode is exited when V_IN–V_OUTexceeds V_{TH_100+}and the device starts switching. The hysteresis

for the 100% Mode detection threshold V_{TH_100+}- V_{TH_100-}will always be positive and will be approximately 50 mV(typ.)

TPS62740, TPS62742

www.ti.com.cn

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

8.6 Typical Characteristics

1000

500

400

300

200

100

900

T_A= −40°C

T_A

25°C

60°C

85°C

T_A

25°C

60°C

85°C

800

700

600

500

400

300

200

100

2.0

2.5

3.0

3.5 4.0

Input Voltage VIN (V)

4.5

5.0

5.5

2.0

2.5

3.0

3.5 4.0

Input Voltage VIN (V)

4.5

5.0

5.5

EN = VIN, V_OUT= 1.8V, CTRL = GND

Device Not Switching

EN = GND

Figure 2. Shutdown Current I_SD

Figure 1. Quiescent Current

1.0

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0.0

T_A= −40°C

T_A

25°C

60°C

85°C

T_A= -40°C

T_A

25°C

60°C

85°C

2.0

2.5

3.0

3.5 4.0

Input Voltage VIN (V)

4.5

5.0

5.5

Figure 4. R_DSONLow Side Mosfet

Figure 3. R_DSONHigh Side Mosfet

1.2

1.1

1.0

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

T_A= −40°C

T_A

25°C

60°C

85°C

0.0

1.8

2.2

2.6

Output Voltage VOUT (V)

3.0

3.4

Figure 5. Load Switch Resistance R_LOAD

TPS62740, TPS62742

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

www.ti.com.cn

9 Detailed Description

9.1 Overview

The TPS6274x is the first step down converter with an ultra low quiescent current consumption (360nA typ.) and

featuring TI's DCS-Control™ topology while maintaining a regulated output voltage. The device extends high

efficiency operation to output currents down to a few micro amperes.

9.2 Functional Block Diagram

CTRL

VOUT

PG Comp

V_FB

UVLO

Ultra Low Power

Reference V_REF= 1.2V

Softstart

V_OUT

Discharge

V_{TH_PG}

VOUT

Load Switch

VSEL 1

VSEL 2

Slew Rate

Control

Internal

V_FBfeedback

divider

CTRL

Auto 100% Mode

Comp

UVLO

Comp

LOAD

100%

Mode

VSEL 3

VSEL 4

network*

VIN

Discharge

UVLO

V_{TH_100}

V_{TH_UVLO}

Power Stage

PMOS

Current

Limit Comparator

VIN

Timer

Min. On

UVLO

DCS

Control

VIN

Limit

High Side

VOUT

Min. OFF

VOUT

Control

Logic

Direct Control

& Compensation

Gate Driver

Anti

Shoot-Through

V_FB

V_REF

NMOS

Limit

Low Side

Error

amplifier

Main

Comparator

GND

Current

Limit Comparator

* typical 50MW

9.3 Feature Description

9.3.1 DCS-Control™

TI's DCS-Control™ (Direct Control with Seamless Transition into Power Save Mode) is an advanced regulation

topology, which combines the advantages of hysteretic and voltage mode control. Characteristics of DCS-

Control™ are excellent AC load regulation and transient response, low output ripple voltage and a seamless

transition between PFM and PWM mode operation. DCS-Control™ includes an AC loop which senses the output

voltage (VOUT pin) and directly feeds the information to a fast comparator stage. This comparator sets the

switching frequency, which is constant for steady state operating conditions, and provides immediate response to

dynamic load changes. In order to achieve accurate DC load regulation, a voltage feedback loop is used. The

internally compensated regulation network achieves fast and stable operation with small external components

and low ESR capacitors.

TPS62740, TPS62742

www.ti.com.cn

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

Feature Description (continued)

The DCS-Control™ topology supports PWM (Pulse Width Modulation) mode for medium and high load

conditions and a Power Save Mode at light loads. During PWM mode, it operates in continuous conduction. The

switching frequency is up to 2MHz with a controlled frequency variation depending on the input voltage. If the

load current decreases, the converter seamlessly enters Power Save Mode to maintain high efficiency down to

very light loads. In Power Save Mode the switching frequency varies nearly linearly with the load current. Since

DCS-Control™ 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. The TPS6274x offers both excellent DC

voltage and superior load transient regulation, combined with very low output voltage ripple, minimizing

interference with RF circuits. At high load currents, the converter operates in quasi fixed frequency PWM mode

operation and at light loads, in PFM (Pulse Frequency Modulation) mode to maintain highest efficiency over the

full load current range. In PFM Mode, the device generates a single switching pulse to ramp up the inductor

current and recharge the output capacitor, followed by a sleep period where most of the internal circuits are

shutdown to achieve a lowest quiescent current. During this time, the load current is supported by the output

capacitor. The duration of the sleep period depends on the load current and the inductor peak current.

During the sleep periods, the current consumption of TPS6274x is reduced to 360nA. This low quiescent current

consumption is achieved by an ultra low power voltage reference, an integrated high impedance (typ. 50MΩ)

feedback divider network and an optimized DCS-Control™ block.

9.3.2 CTRL / Output Load

With the CTRL pin set to high, the LOAD pin is connected to the VOUT pin via an load switch and can power up

an additional, temporarily used sub-system. The load switch is slew rate controlled to support soft switching and

not to impact the regulated output VOUT. If CTRL pin is pulled to GND, the LOAD pin is disconnected from the

VOUT pin and internally connected to GND by an internal discharge switch. When CTRL pin is set to high, the

Quiescent current of the DCS control block is increased to typ. 12.5µA. This ensures excellent transient response

on both outputs VOUT and LOAD in case of a sudden load step at the LOAD output. The CTRL pin can be

controlled by a micro controller.

9.3.3 Enable / Shutdown

The DC/DC converter is activated when the EN pin is set to high. For proper operation, the pin must be

terminated and must not be left floating. With the EN pin set to low, the device enters shutdown mode with less

than typ. 70nA current consumption.

9.3.4 Power Good Output (PG)

The Power Good comparator features an open drain output. The PG comparator is active with EN pin set to high

and V_INis above the threshold V_{TH_UVLO+}. It is driven to high impedance once V_OUTtrips the threshold V_{TH_PG+}for

rising V_OUT. The output is pulled to low level once V_OUTfalls below the PG hysteresis, V_{PG_hys}. The output is also

pulled to low level in case the input voltage V_INfalls below the undervoltage lockout threshold V_{TH_UVLO-}or the

device is disabled with EN = low. The power good output (PG) can be used as an indicator for the system to

signal that the converter has started up and the output voltage is in regulation.

9.3.5 Output Voltage Selection (VSEL1 – 4)

The TPS6274x doesn't require an external resistor divider network to program the output voltage. The device

integrates a high impedance (typ. 50MΩ) feedback resistor divider network which is programmed by the pins

VSEL 1-4. TPS6274x supports an output voltage range of 1.8V to 3.3V in 100mV steps. The output voltage can

be changed during operation and supports a simple dynamic output voltage scaling, shown in Figure 47. The

output voltage is programmed according to table Table 1.

9.3.6 Softstart

When the device is enabled, the internal reference is powered up and after the startup delay time t_{Startup_delay}has

expired, the device enters softstart, starts switching and ramps up the output voltage. During softstart the device

operates with a reduced current limit, I_{LIM_softstart}, of typ. 1/4 of the nominal current limit. This reduced current limit

is active during the softstart time t_Softstart. The current limit is increased to its nominal value, I_LIMF, once the

softstart time has expired.

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Feature Description (continued)

9.3.7 Undervoltage Lockout UVLO

The device includes an under-voltage lockout (UVLO) comparator which prevents the device from misoperation

at too low input voltages. The UVLO comparator becomes active once the device is enabled with EN set to high.

Once the input voltage trips the UVLO threshold V_{TH_UVLO+}(typically 2.075V) for rising V_IN, the UVLO comparator

releases the device for start up and operation. With a falling input voltage, the device operates down to the

UVLO threshold level V_{TH_UVLO-}(typically 1.925V). Once this threshold is tripped, the device stops switching, the

load switch at pin LOAD is disabled and both rails, VOUT and LOAD are discharged. The converter starts

operation again once the input voltage trips the rising UVLO threshold level V_{TH_UVLO+}

9.4 Device Functional Modes

9.4.1 VOUT And LOAD Output Discharge

Both the VOUT pin and the LOAD pin feature a discharge circuit to connect each rail to GND, once they are

disabled. This feature prevents residual charge voltages on capacitors connected to these pins, which may

impact proper power up of the main- and sub-system. With CTRL pin pulled to low, the discharge circuit at the

LOAD pin becomes active. With the EN pin pulled to low, the discharge circuits at both pins VOUT and Load are

active. The discharge circuits of both rails VOUT and LOAD are associated with the UVLO comparator as well.

Both discharge circuits become active once the UVLO comparator triggers and the input voltage V_INhas dropped

below the UVLO comparator threshold V_{TH_UVLO-}(typ. 1.925V).

9.4.2 Automatic Transition Into 100% Mode

Once the input voltage comes close to the output voltage, the DC/DC converter stops switching and enters 100%

duty cycle operation. It connects the output VOUT via the inductor and the internal high side MOSFET switch to

the input VIN, once the input voltage V_INfalls below the 100% mode enter threshold, V_{TH_100-}. The DC/DC

regulator is turned off, not switching and therefore it generates no output ripple voltage. Because the output is

connected to the input, the output voltage tracks the input voltage minus the voltage drop across the internal high

side switch and the inductor caused by the output current. Once the input voltage increases and trips the 100%

mode leave threshold, V_{TH_100+}, the DC/DC regulator turns on and starts switching again. See Figure 6,

Figure 49, Figure 50, Figure 51.

V_IN

V_IN,

V_OUT

100%

Mode

100%

Mode

V_{TH_100+}

V_{TH_100-}

Step Down Operation

V_OUT

tracks V_IN

V_OUT

tracks V_IN

V_{TH_PG+}

V_UVLO+

V_{PG_Hys}

V_UVLO-

V_OUT

discharge

t_softstart

High

Low

Figure 6. Automatic 100% Mode Transition

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ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

Device Functional Modes (continued)

9.4.3 Internal Current Limit

The TPS6274x integrates a current limit on the high side, as well the low side MOSFETs to protect the device

against overload or short circuit conditions. The peak current in the switches is monitored cycle by cycle. If the

high side MOSFET current limit is reached, the high side MOSFET is turned off and the low side MOSFET is

turned on until the current decreases below the low side MOSFET current limit.

9.4.4 Dynamic Voltage Scaling with VSEL Interface

During operation, the output voltage of the device can be changed, see Figure 47. The device will not actively

ramp down the output voltage from a higher to a lower level.

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10 Application and Implementation

10.1 Application Information

The TPS6274x devices are a step down converter family featuring typ. 360nA quiescent current and operating

with a tiny 2.2µH inductor and 10µF output capacitor. This new DCS-Control^TMbased devices extend the light

load efficiency range below 10µA load currents. TPS62740 supports output currents up to 300mA, TPS62742 up

to 400mA. The devices operate from rechargeable Li-Ion batteries, Li-primary battery chemistries such as Li-

SOCl2, Li-MnO2 and two or three cell alkaline batteries.

10.2 Typical Application

V_IN

2.2V - 5.5V

2.1V

Main rail

TPS62740

L 2.2mH

V_CC

VIN

C_OUT

C_IN

VOUT

10mF

VSEL1

VSEL2

VSEL3

VSEL4

GND

R_{pull up}

CTRL

LOAD

Switched

supply rail

Subsystem

(Sensors)

Figure 7. TPS62740 Typical Application Circuit

V_IN

4V - 5.5V

3.3V

400mA

TPS62742

L 2.2mH

V_CC

VIN

C_OUT

10mF

C_IN

VOUT

10mF

VSEL1

VSEL2

VSEL3

VSEL4

GND

R_{pull up}

CTRL

LOAD

Switched

supply rail

Subsystem

Figure 8. TPS62742 Typical Application Circuit

10.2.1 Design Requirements

The TPS6274x is a highly integrated DC/DC converter. The output voltage is set via a VSEL pin interface without

any additional external components. For proper operation only a input- and output capacitor and an inductor is

required. The integrated load switch doesn't require a capacitor on its LOAD pin. Table 2 shows the components

used for the application characteristic curves.

Table 2. Components for Application Characteristic Curves

Reference

TPS62740/42

CIN, COUT, CLOAD

Description

Value

Manufacturer

Texas Instruments

Murata

360nA Iq step down converter

Ceramic capacitor GRM188R60J106M

Inductor LPS3314

10µF

2.2µH

Coilcraft

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10.2.2 Detailed Design Procedure

Table 3 shows the recommended output filter components. The TPS6274x is optimized for operation with a

2.2µH inductor and with 10µF output capacitor.

Table 3. Recommended LC Output Filter Combinations

Output Capacitor Value [µF]⁽²⁾

Inductor Value [µH]⁽¹⁾

4.7µF

10µF

22µF

(3)

2.2

√

(1) Inductor tolerance and current de-rating is anticipated. The effective inductance can vary by 20% and -

30%.

(2) Capacitance tolerance and bias voltage de-rating is anticipated. The effective capacitance can vary by

20% and -50%.

(3) This LC combination is the standard value and recommended for most applications.

10.2.2.1 Inductor Selection

The inductor value affects its peak-to-peak ripple current, the PWM-to-PFM transition point, the output voltage

ripple and the efficiency. The selected inductor has to be rated for its DC resistance and saturation current. The

inductor ripple current (ΔI_L) decreases with higher inductance and increases with higher V_INor V_OUTand can be

estimated according to Equation 1.

Equation 2 calculates the maximum inductor current under static load conditions. The saturation current of the

inductor should be rated higher than the maximum inductor current, as calculated with Equation 2. This is

recommended because during a heavy load transient the inductor current rises above the calculated value. A

more conservative way is to select the inductor saturation current above the high-side MOSFET switch current

limit, I_LIMF

Vout

Vin

DI_L= Vout ´

L ´ ¦

(1)

(2)

= I

Lmax

outmax

With:

f = Switching Frequency

L = Inductor Value

ΔI_L= Peak to Peak inductor ripple current

I_Lmax= Maximum Inductor current

In DC/DC converter applications, the efficiency is essentially affected by the inductor AC resistance (i.e. quality

factor) and by the inductor DCR value. Increasing the inductor value produces lower RMS currents, but degrades

transient response. For a given physical inductor size, increased inductance usually results in an inductor with

lower saturation current.

The total losses of the coil consist of both the losses in the DC resistance (R_DC) and the following frequency-

dependent components:

•

The losses in the core material (magnetic hysteresis loss, especially at high switching frequencies)

Additional losses in the conductor from the skin effect (current displacement at high frequencies)

Magnetic field losses of the neighboring windings (proximity effect)

Radiation losses

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The following inductor series from different suppliers have been used:

Table 4. List Of Inductors⁽¹⁾

INDUCTANCE [µH]

DIMENSIONS [mm³]

3.3 x 3.3 x 1.4

2.5 x 3.0 x 1.5

2.0 × 1.2 × 1.0

2.5 x 2.0 x 1.2

2.0 x 1.2 x 1.0

INDUCTOR TYPE

LPS3314

SUPPLIER

Coilcraft

TDK

2.2

VLF302515MT

MIPSZ2012 2R2

MIPSA2520 2R2

MDT2012CH2R2

FDK

TOKO

(1) See Third-party Products Disclaimer

10.2.2.2 DC/DC Output Capacitor Selection

The DCS-Control™ scheme of the TPS6274x allows the use of tiny ceramic capacitors. Ceramic capacitors with

low ESR values have the lowest output voltage ripple and are recommended. The output capacitor requires

either an X7R or X5R dielectric. Y5V and Z5U dielectric capacitors, aside from their wide variation in capacitance

over temperature, become resistive at high frequencies. At light load currents, the converter operates in Power

Save Mode and the output voltage ripple is dependent on the output capacitor value and the PFM peak inductor

current. A larger output capacitors can be used, but it should be considered that larger output capacitors lead to

an increased leakage current in the capacitor and may reduce overall conversion efficiency. Furthermore, larger

output capacitors impact the start up behavior of the DC/DC converter.

10.2.2.3 Input Capacitor Selection

Because the buck converter has a pulsating input current, a low ESR input capacitor is required for best input

voltage filtering to ensure proper function of the device and to minimize input voltage spikes. For most

applications a 10µF is sufficient. The input capacitor can be increased without any limit for better input voltage

filtering.

Table 5 shows a list of tested input/output capacitors.

Table 5. List Of Capacitors⁽¹⁾

CAPACITANCE [μF]

SIZE

CAPACITOR TYPE

SUPPLIER

0603

GRM188R60J106ME84

Murata

(1) See Third-party Products Disclaimer

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ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

10.2.3 Application Curves

95.0

90.0

85.0

80.0

75.0

70.0

65.0

60.0

55.0

50.0

45.0

40.0

V_IN= 2.7V

V_IN= 3.3V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

V_IN= 2.7V

V_IN= 3.3V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

0.001

0.01

0.1

100

1000

0.001

0.01

0.1

100

1000

Output Current (mA)

C_OUT= 10 µF (0603)

CTRL = GND

C_OUT= 10 µF (0603)

CTRL = GND

L = 2.2 µH (LPS3314 2R2)

L = 2.2 μH (LPS3314 2R2)

Figure 9. Efficiency V_OUT= 1.8V

Figure 10. Efficiency V_OUT= 2.1V

100

V_IN= 3.0V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

V_IN= 3.3V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

0.001

0.01

0.1

100

0.001

0.01

0.1

100

1000

Output Current I_OUT(mA)

Output Current (mA)

C001

C_OUT= 10 µF (0603)

CTRL = GND

C_OUT= 10 µF,

CTRL = GND.

L = 2.2 µH (VLF302515)

L = 2.2 µH (LPS3314 2R2)

Figure 12. Efficiency V_OUT= 2.5V

Figure 11. Efficiency VOUT = 3.3V TPS62742

100

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

I_OUT= 1mA

I_OUT= 2mA

I_OUT= 5mA

I_OUT= 10mA

I_OUT= 100mA

I_OUT= 50mA

I_OUT= 200mA

2.5

3.5 4

Input Voltage V_IN(V)

4.5

5.5

0.001

0.01

0.1

100

1000

Output Current (mA)

C_OUT= 10 µF (0603)

CTRL = GND

C_OUT= 10 µF (0603)

CTRL = GND

L = 2.2 µH (LPS3314 2R2)

Figure 14. Efficiency V_OUT= 1.8V

Figure 13. Efficiency V_OUT= 3.3V

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100

I_OUT= 1mA

I_OUT= 2mA

I_OUT= 5mA

I_OUT= 1mA

I_OUT= 2mA

I_OUT= 5mA

I_OUT= 10mA

I_OUT= 100mA

I_OUT= 1mA

I_OUT= 10mA

I_OUT= 100mA

I_OUT= 1mA

I_OUT= 10mA

I_OUT= 50mA

I_OUT= 200mA

I_OUT= 10mA

I_OUT= 50mA

I_OUT= 200mA

2.5

3.5

Input Voltage V_IN(V)

4.5

5.5

2.5

3.5

Input Voltage V_IN(V)

4.5

5.5

C_OUT= 10 µF (0603)

CTRL = GND

C_OUT= 10 µF (0603)

CTRL = GND

L = 2.2 µH (LPS3314 2R2)

Figure 15. Efficiency V_OUT= 2.1V

Figure 16. Efficiency V_OUT= 2.5V

100

1.854

1.836

1.818

1.8

I_OUT= 1mA

I_OUT= 2mA

I_OUT= 5mA

1.782

1.764

1.746

I_OUT= 10mA

I_OUT= 100mA

I_OUT= 1mA

I_OUT= 10mA

I_OUT= 50mA

I_OUT= 200mA

V_IN= 2.7V

V_IN= 3.3V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

3.5

4.5

Input Voltage V_IN(V)

5.5

0.001

0.01

0.1

Output Current I_OUT(mA)

100

1000

C_OUT= 10 µF (0603)

CTRL = GND

C_OUT= 10 µF (0603)

CTRL = GND

L = 2.2 µH (LPS3314 2R2)

Figure 17. Efficiency V_OUT= 3.3V

Figure 18. Output Voltage V_OUT= 1.8V

2.163

2.142

2.121

2.1

2.575

2.55

2.525

2.5

2.079

2.058

2.037

2.475

2.45

V_IN= 2.7V

V_IN= 3.3V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

V_IN= 3.3V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

2.425

0.001

0.01

0.1

Output Current I_OUT(mA)

100

1000

0.01

0.1

Output Current I_OUT(mA)

100

1000

C_OUT= 10 µF (0603)

CTRL = GND

C_OUT= 10 µF (0603)

CTRL = GND

L = 2.2 µH (LPS3314 2R2)

Figure 19. Output Voltage V_OUT= 2.1V

Figure 20. Output Voltage V_OUT= 2.5V

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3.399

2000

1500

1000

500

3.366

3.333

3.3

3.267

3.234

3.201

V_IN= 2.5V

V_IN= 3.0V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

VIN = 3.6V

VIN = 4.2V

VIN = 5.0V

0.001

0.01

0.1

Output Current I_OUT(mA)

100

1000

100

150

200

250

300

Output Current (mA)

C_OUT= 10 µF (0603)

CTRL = GND

L = 2.2 µH (LPS3314 2R2)

C_OUT= 10 µF

L = 2.2 µH

Figure 21. Output Voltage V_OUT= 3.3V

Figure 22. Typical Switching Frequency V_OUT= 1.8V

2000

V_IN= 2.7V

V_IN= 3.0V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

1500

1000

500

V_IN= 2.7V

V_IN= 3.0V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

100

150

200

250

300

100

150

200

250

300

Output Current (mA)

C_OUT= 10 µF (0603)

CTRL = GND

L = 2.2 µH

C_OUT= 10 µF

L = 2.2 µH

Figure 23. Typical Output Ripple Voltage V_OUT= 1.8V

Figure 24. Typical Switching Frequency V_OUT= 2.1V

2500

V_IN= 2.7V

V_IN= 3.0V

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

2000

1500

1000

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

500

100

150

200

250

300

100

150

200

250

300

Output Current (mA)

C_OUT= 10 µF (0603)

CTRL = GND

L = 2.2 µH

C_OUT= 10 µF

L = 2.2 µH

Figure 25. Typical Output Ripple Voltage V_OUT= 2.1V

Figure 26. Typical Switching Frequency V_OUT= 3.0V

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2.50

2.45

2.40

2.35

2.30

2.25

2.20

2.15

2.10

2.05

2.00

V_IN= 3.6V

V_IN= 4.2V

V_IN= 5.0V

I_OUT= 10mA, rising V_IN

I_OUT= 10mA, falling V_IN

I_OUT= 50mA, rising V_IN

I_OUT= 50mA, falling V_IN

I_OUT= 100mA, rising V_IN

I_OUT= 100mA, falling V_IN

100

150

200

250

300

2.20

2.25

2.30

2.35

2.40

2.45

2.50

Output Current (mA)

Input Voltage V_IN(V)

C_OUT= 10 µF (0603)

CTRL = GND

L = 2.2 µH

L = 2.2 µH (LPS3314)

Figure 27. Typical Output Ripple Voltage V_OUT= 3.0V

Figure 28. 100% Mode Transition V_OUT2.1V

2.90

3.60

3.55

3.50

3.45

3.40

3.35

3.30

3.25

3.20

3.15

3.10

3.05

3.00

I_OUT= 10mA, rising V_IN

I_OUT= 10mA, falling V_IN

I_OUT= 50mA, rising V_IN

I_OUT= 50mA, falling V_IN

I_OUT= 100mA, rising V_IN

I_OUT= 100mA, falling V_IN

2.85

2.80

2.75

2.70

2.65

2.60

2.55

2.50

2.45

2.40

I_OUT= 10mA, rising V_IN

I_OUT= 10mA, falling V_IN

I_OUT= 50mA, rising V_IN

I_OUT= 50mA, falling V_IN

I_OUT= 100mA, rising V_IN

I_OUT= 100mA, falling V_IN

2.40 2.45 2.50 2.55 2.60 2.65 2.70 2.75 2.80 2.85 2.90

3.20

3.30

3.40

3.50

3.60

3.70

Input Voltage V_IN(V)

L = 2.2 µH (LPS3314)

Figure 29. 100% Mode Transition V_OUT2.5V

L = 2.2 µH (LPS3314)

Figure 30. 100% Mode Transition V_OUT3.3V

V_IN= 3.6 V

I_OUT= 10 µA

C_OUT= 10 µF

L = 2.2 µH

V_IN= 3.6 V

I_OUT= 1 mA

L = 2.2 µH

CTRL = GND

C_OUT= 10 µF

CTRL = GND

Figure 31. Typical Operation I_Load= 10µA V_OUT= 1.8V

Figure 32. Typical Operation I_Load= 1ma, V_OUT= 1.8V

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V_IN= 3.6 V

C_OUT= 10 µF

I_OUT= 25 mA

L = 2.2 µH

V_IN= 3.6 V

I_OUT= 150 mA

C_OUT= 10 µF

L = 2.2 µH

CTRL = GND

Figure 33. Typical Operation I_Load= 25mA, V_OUT= 1.8V

Figure 34. Typical Operation I_Load= 150ma, V_OUT= 1.8V

V_IN= 3.6 V I_OUT= 50 µA to 10 mA

C_OUT= 10 µF

L = 2.2 µH

V_IN= 3.6 V

I_OUT= 0.5 mA to 150 mA

C_OUT= 10 µF

L = 2.2 µH

CTRL = GND

CTRL = V_IN

Figure 35. Load Transient Response V_OUT= 1.8V

Figure 36. Load Transient Response V_OUT= 2.1V

V_IN= 3.6 V, V_OUT= 2.1 V

L = 2.2 µH

C_OUT= 10 µF

V_IN= 3.6 V, V_OUT= 2.1 V

L = 2.2 µH,

C_OUT= 10 µF

Loadstep at V_OUT0 mA to 100 mA,

1 µs rise/ fall time, 70 µs / 7 ms

Loadstep at V_OUT0 mA to 100 mA,

1 µs rise/fall time; 70 µs / 7 ms

Figure 37. Load Transient Response CTRL = GND

Figure 38. Load Transient Response CTRL = VIN

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V_IN= 3.6 V / 4.2 V

V_OUT= 2.1 V

C_OUT= 10 µF

L = 2.2 µH

V_IN= 3.6 V / 4.2 V

V_OUT= 2.1 V

C_OUT= 10 µF

L = 2.2 µH

CTRL = GND

Figure 39. Line Transient Response I_OUT=10mA

Figure 40. Line Transient Response I_OUT= 100mA

V_IN= 3.6 V

I_OUT= 50 µA to 300 mA

C_OUT= 10 µF

L = 2.2 µH

CTRL = GND

V_IN= 3.6 V,

V_OUT= V_LOAD= 2.1 V

C_LOAD= 10 µF

CTRL = V_IN

L = 2.2 µH

I_OUT= 0 mA

C_OUT= 10 µF

I_LOAD= 0 to 50 mA to 0 mA

Figure 41. AC Load Sweep V_OUT= 2.1V

Figure 42. Load Step At Load Output

V_LOADslew rate

controlled

V_LOADDischarge

V_IN= 3.6 V

I_OUT= 0 mA

V_OUT= 2.1 V

I_LOAD= 0 mA

V_IN= 3.6 V

R_OUT= 100 Ω

V_OUT= 2.1 V

C_OUT= 10 µF

CTRL = GND

L = 2.2 µH

C_OUT= 10 µF C_LOAD= 10 µF

L = 2.2 µH

Figure 43. Load Output On / Off

Figure 44. Device Enable And Start Up

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V_IN= 3.6 V

R_OUT= 100 Ω

V_OUT= 2.1 V

C_OUT= 10 µF

CTRL = GND

L = 2.2 µH

V_IN= 3.6 V

V_OUT= V_LOAD= 2.1 V CTRL = V_IN

C_OUT= C_LOAD= 10 µF L = 2.2 µH

R_OUT= 100 Ω,

I_LOAD= 0 mA

Figure 45. V_OUTRamp Up After Enable

Figure 46. V_OUTRamp Up With Activated Load Switch

V_IN= 3.6 V

Ramp up / Down

C_OUT= 10 µF

L = 2.2 µH

CTRL = GND

C_OUT= 10 µF

I_OUT= 5 mA

CTRL = GND

L = 2.2 µH

VSEL 3+4 toggled

VSEL 1+2 = GND

V_IN= ramp up/down 0 V to 5 V, 150 ms,

Output resistance 50 Ω

Figure 47. Dynamic Output Voltage Scaling

V_OUT= 1.8V/3.0V

Figure 48. Input Voltage Ramp Up/Down

V_OUT= 1.8V

100% mode operation,

high side MOSFET turned on

100% mode operation,

high side MOSFET turned on

C_OUT= 10 µF

L = 2.2 µH

CTRL = GND

C_OUT= 10 µF

L = 2.2 µH

CTRL = GND

V_IN= ramp up/down 0 V to 5 V, 150 ms,

Output resistance 50 Ω

V_IN= ramp up/down 0 V to 5 V, 150 ms,

Output resistance 50 Ω

Figure 49. Input Voltage Ramp Up/Down V_OUT= 2.6V

Figure 50. Input Voltage Ramp Up/Down V_OUT= 3.3V

TPS62740, TPS62742

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

www.ti.com.cn

High side mosfet turned on

100% Mode

Leave / Enter

V_OUT= 3.0 V

C_OUT= 10 µF

L = 2.2 µH, CTRL = GND

V_IN= ramp up /down 2.8 V to 3.7 V,

Output resistance 50 Ω

Figure 51. Enter/Leave 100% Mode Operation

10.3 System Example

TPS62740

V_BAT

VSEL1

VSEL2

VSEL3

VIN

Voltage

Selection

V_{OUT Main}

R_{Pull Up}

C_IN

VSEL4

Power Good

Control Sub-System

Master

MCU

CTRL

V_{OUT Main}

Main

Supply

GND

VOUT

LOAD

Switched Supply

Radio

Sub-

System

Sensor

Figure 52. Example Of Implementation In A Master MCU Based System

TPS62740, TPS62742

www.ti.com.cn

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

11 Power Supply Recommendations

The power supply to the TPS6274x needs to have a current rating according to the supply voltage, output

voltage and output current of the TPS6274x.

12 Layout

12.1 Layout Guidelines

As for all switching power supplies, the layout is an important step in the design. Care must be taken in board

layout to get the specified performance. If the layout is not carefully done, the regulator could show poor line

and/or load regulation, stability issues as well as EMI problems and interference with RF circuits. It is critical to

provide a low inductance, impedance ground path. Therefore, use wide and short traces for the main current

paths. The input capacitor should be placed as close as possible to the IC pins VIN and GND. The output

capacitor should be placed close between VOUT and GND pins. The VOUT line should be connected to the

output capacitor and routed away from noisy components and traces (e.g. SW line) or other noise sources. The

exposed thermal pad of the package and the GND pin should be connected. See Figure 53 for the

recommended PCB layout.

12.2 Layout Example

VSEL

EN 1-4 PG

TPS62740

GND

LOAD

VIN

VOUT

CIN

(0603)

COUT

(0603)

L(0805)

4.3 mm

Solution size: 31mm²

Height: 1mm max.

Figure 53. Recommended PCB Layout

TPS62740, TPS62742

ZHCS342B –NOVEMBER 2013–REVISED JULY 2014

www.ti.com.cn

13 器件和文档支持

13.1 器件支持

13.1.1 第三方产品免责声明

TI 发布的与第三方产品或服务有关的信息，不能构成与此类产品或服务或保修的适用性有关的认可，不能构成此类

产品或服务单独或与任何 TI 产品或服务一起的表示或认可。

13.2 文档支持

13.2.1 相关文档ꢀ

另请参见《TPS62740EVM-186 评估模块用户指南》，SLVU949；和应用笔记《精确测量超低 IQ 器件的效

率》，SLYT558，以便在 PFM 模式操作下精确测量效率。

13.3 相关链接

以下表格列出了快速访问链接。范围包括技术文档、支持与社区资源、工具和软件，并且可以快速访问样片或购买

链接。

表 6. 相关链接

器件

产品文件夹

请单击此处

样片与购买

请单击此处

技术文档

请单击此处

工具与软件

请单击此处

支持与社区

请单击此处

TPS62740

TPS62742

13.4 商标

DCS-Control is a trademark of Texas Instruments.

is a registered trademark of ~Bluetooth SIG, Inc.

13.5 静电放电警告

这些装置包含有限的内置 ESD 保护。存储或装卸时，应将导线一起截短或将装置放置于导电泡棉中，以防止 MOS 门极遭受静电损

伤。

13.6 术语表

SLYZ022 — TI 术语表。

这份术语表列出并解释术语、首字母缩略词和定义。

14 机械封装和可订购信息

以下页中包括机械封装和可订购信息。这些信息是针对指定器件可提供的最新数据。这些数据会在无通知且不对

本文档进行修订的情况下发生改变。欲获得该数据表的浏览器版本，请查阅左侧的导航栏。

PACKAGE OPTION ADDENDUM

www.ti.com

11-Aug-2022

PACKAGING INFORMATION

Orderable Device

Status Package Type Package Pins Package

Eco Plan

Lead finish/

Ball material

MSL Peak Temp

Op Temp (°C)

Device Marking

Samples

Drawing

Qty

(1)

(2)

(3)

(4/5)

(6)

TPS62740DSSR

TPS62740DSST

TPS62742DSSR

TPS62742DSST

ACTIVE

WSON

DSS

3000 RoHS & Green

250 RoHS & Green

3000 RoHS & Green

250 RoHS & Green

NIPDAU

Level-1-260C-UNLIM

-40 to 85

62740

62742

Samples

NIPDAU

⁽¹⁾The marketing status values are defined as follows:

ACTIVE: Product device recommended for new designs.

LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.

NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.

PREVIEW: Device has been announced but is not in production. Samples may or may not be available.

OBSOLETE: TI has discontinued the production of the device.

⁽²⁾RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance

do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may

reference these types of products as "Pb-Free".

RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.

Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based

flame retardants must also meet the <=1000ppm threshold requirement.

⁽³⁾MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.

⁽⁴⁾There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.

⁽⁵⁾Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation

of the previous line and the two combined represent the entire Device Marking for that device.

(6)

Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two

lines if the finish value exceeds the maximum column width.

Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information

provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and

Addendum-Page 1

PACKAGE OPTION ADDENDUM

www.ti.com

11-Aug-2022

continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.

TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.

In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.

Addendum-Page 2

PACKAGE MATERIALS INFORMATION

www.ti.com

9-Aug-2022

TAPE AND REEL INFORMATION

REEL DIMENSIONS

TAPE DIMENSIONS

Reel

Diameter

Cavity

A0 Dimension designed to accommodate the component width

B0 Dimension designed to accommodate the component length

K0 Dimension designed to accommodate the component thickness

Overall width of the carrier tape

P1 Pitch between successive cavity centers

Reel Width (W1)

QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE

Sprocket Holes

Q1 Q2

Q3 Q4

Q1 Q2

Q3 Q4

User Direction of Feed

Pocket Quadrants

*All dimensions are nominal

Device

Package Package Pins

Type Drawing

SPQ

Reel

Pin1

Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant

(mm) W1 (mm)

TPS62740DSSR

TPS62740DSST

TPS62742DSSR

TPS62742DSST

WSON

DSS

3000

250

180.0

8.4

2.25

3.25

1.05

4.0

8.0

3000

250

Pack Materials-Page 1

PACKAGE MATERIALS INFORMATION

www.ti.com

9-Aug-2022

TAPE AND REEL BOX DIMENSIONS

Width (mm)

*All dimensions are nominal

Device

Package Type Package Drawing Pins

SPQ

Length (mm) Width (mm) Height (mm)

TPS62740DSSR

TPS62740DSST

TPS62742DSSR

TPS62742DSST

WSON

DSS

3000

250

182.0

20.0

3000

250

Pack Materials-Page 2

PACKAGE OUTLINE

DSS0012A

WSON - 0.8 mm max height

SCALE 5.000

PLASTIC SMALL OUTLINE - NO LEAD

2.1

1.9

0.35

0.25

PIN 1 INDEX AREA

3.1

2.9

0.3

0.2

DETAIL

OPTIONAL TERMINAL

TYPICAL

0.8 MAX

SEATING PLANE

0.08 C

0.9±0.1

4X (0.2)

(0.7)

(0.2) TYP

EXPOSED

THERMAL PAD

0.05

0.00

SEE TERMINAL

DETAIL

2.5

2±0.1

10X 0.5

0.35

0.25

0.3

0.2

12X

PIN 1 ID

(OPTIONAL)

0.1

C A

0.05

4222684/A 02/2016

NOTES:

1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing

per ASME Y14.5M.

2. This drawing is subject to change without notice.

3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.

www.ti.com

EXAMPLE BOARD LAYOUT

DSS0012A

WSON - 0.8 mm max height

PLASTIC SMALL OUTLINE - NO LEAD

(0.9)

12X (0.5)

12X (0.25)

SYMM

10X (0.5)

(2)

(0.75)

(R0.05) TYP

(

0.2) VIA TYP

NOTE 5

SYMM

(1.9)

LAND PATTERN EXAMPLE

SCALE:20X

0.07 MIN

ALL AROUND

0.07 MAX

ALL AROUND

SOLDER MASK

OPENING

METAL UNDER

SOLDER MASK

METAL

SOLDER MASK

OPENING

NON SOLDER MASK

DEFINED

(PREFERRED)

SOLDER MASK

DEFINED

SOLDER MASK DETAILS

4222684/A 02/2016

NOTES: (continued)

4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature

number SLUA271 (www.ti.com/lit/slua271).

5. Vias are optional depending on application, refer to device data sheet. If some or all are implemented, recommended via locations are shown.

It is recommended that vias located under solder paste be filled, plugged or tented.

www.ti.com

EXAMPLE STENCIL DESIGN

DSS0012A

WSON - 0.8 mm max height

PLASTIC SMALL OUTLINE - NO LEAD

SYMM

12X (0.5)

12X (0.25)

METAL

TYP

SYMM

10X (0.5)

(0.9)

(R0.05) TYP

(0.9)

(1.9)

SOLDER PASTE EXAMPLE

BASED ON 0.125 mm THICK STENCIL

EXPOSED PAD 13:

90% PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE

SCALE:20X

4222684/A 02/2016

NOTES: (continued)

6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate

design recommendations.

www.ti.com

重要声明和免责声明

TI“按原样”提供技术和可靠性数据（包括数据表）、设计资源（包括参考设计）、应用或其他设计建议、网络工具、安全信息和其他资源，

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证并测试您的应用，(3) 确保您的应用满足相应标准以及任何其他功能安全、信息安全、监管或其他要求。

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TI 反对并拒绝您可能提出的任何其他或不同的条款。IMPORTANT NOTICE

邮寄地址：Texas Instruments, Post Office Box 655303, Dallas, Texas 75265

TPS62740 [TI]

相关型号：

TPS62740DSSR

TPS62740DSST

TPS62742

TPS62742DSSR

TPS62742DSST

TPS62743

TPS627431YFPR

TPS627431YFPT

TPS62743YFPR

TPS62743YFPT

TPS62745

TPS627451