DEVICE INFORMATION

PINOUT

DRVH2

VIN

VREG3

EN2

DRVH1

V5SW

RF

EN1

PGOOD2

SKIPSEL2

CSP2

CSN2

PGOOD1

SKIPSEL1

CSP1

CSN1

24

23

22

21

20

19

18

17

1

2

3

4

5

6

7

8

TPS51122

RTVPACKAGE

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TPS51222

www.ti.com............................................................................................................................................................................................... SLUS908 – JANUARY 2009

PIN FUNCTIONS

PIN

I/O

DESCRIPTION

NAME

NO.

COMP1

10

Loop compensation pin for current mode (error amplifier output). Connect R (and C if required) from this pin

I

to VREF2 for proper loop compensation with current mode operation.

COMP2

15

CSN1

8

Current sense comparator inputs (–). See the current sensing scheme section. Used as power supply for the

I

current sense circuit for 5 V or higher output voltage setting. Also, used for output discharge terminal.

CSN2

17

CSP1

7

Current sense comparator inputs (+). An RC network with high quality X5R or X7R ceramic capacitor should

I/O

be used to extract voltage drop across DCR. 0.1-

µF is a good value to start the design. See the current

CSP2

18

sensing scheme section for more details.

DRVH1

1

High-side MOSFET gate driver outputs. Source 1.7

Ω, sink 1.0 Ω, SW-node referenced floating driver. Drive

O

voltage corresponds to VBST to SW voltage.

DRVH2

24

DRVL1

30

O

Low-side MOSFET gate driver outputs. Source 1.3

Ω, sink 0.7 Ω, and GND referenced driver.

DRVL2

27

VREF2 and VREG5 linear regulators enable pin. When turning on, apply greater than 1.2 V and less than 6

EN

12

I

V. Connect to GND to disable.

EN1

4

Channel 1 and channel 2 SMPS Enable Pins. When turning on, apply greater than 0.55 V and less than 6 V.

I

Connect to GND to disable. Adjustable soft-start capacitance to be attached here.

EN2

21

GND

28

–

Ground

IMON1

11

O

Current monitor outputs for channel 1 and channel 2. Adding an RC filter is recommended.

IMON2

14

PGOOD1

5

Powergood window comparator outputs for channel 1 and channel 2. The recommended applied voltage

O

should be less than 6 V, and the recommended pull-up resistance value is from 100 k

Ω to 1 MΩ.

PGOOD2

20

Frequency setting pin. Connect a frequency setting resistor to (signal) GND. Connect to an external clock for

RF

3

I/O

synchronization.

Copyright © 2009, Texas Instruments Incorporated

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