SW

BST

FB

CS

CSG

RT

VIN

PGD

SGND

SS

Exposed Pad on Bottom

Connect to Ground

1

2

3

4

5

10

9

8

7

6

LM34922

SNVS813A – JUNE 2012 – REVISED MARCH 2013

www.ti.com

Connection Diagram

Figure 1. Top View

10-Lead HVSSOP-PowerPAD

PIN DESCRIPTIONS

Pin No.

Name

Description

Application Information

1

VIN

Input supply voltage

Operating input range is 6V to 28V. Transient capability is 30V. A low ESR

capacitor must be placed as close as possible to the VIN and SGND pins.

2

RT

On-time Control

An external resistor from VIN to this pin sets the buck switch on-time, and the

switching frequency.

3

PGD

Power Good

Logic output indicates when the voltage at the FB pin has increased to above

95% of the internal reference voltage. Hysteresis is provided. An external

pull-up resistor to a voltage less than 7V is required.

4

SS

Soft-Start

An internal current source charges an external capacitor to provide the soft-

start function.

5

SGND

Signal Ground

Ground for all internal circuitry other than the current limit sense circuit.

6

FB

Feedback

Internally connected to the regulation comparator. The regulation level is

2.51V.

7

CSG

Current Sense Ground

Ground connection for the current limit sensing circuit. Connect to ground

and to the current sense resistor.

8

CS

Current sense

Connect to the current sense resistor and the anode of the free-wheeling

diode.

9

SW

Switching Node

Internally connected to the buck switch source. Connect to the external

inductor, cathode of the free-wheeling diode, and bootstrap capacitor.

10

BST

Bootstrap capacitor connection of the

Connect a 0.1µF capacitor from SW to this pin. The capacitor is charged

buck switch gate driver.

during the buck switch off-time via an internal diode.

These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam

during storage or handling to prevent electrostatic damage to the MOS gates.

2

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