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SC2620

POWER MANAGEMENT

Pin Configuration

Ordering Information

Underside metal must be soldered to ground.

Pin #

Pin Name

Pin Function

1, 8

FB1, FB2

The inverting inputs of the error amplifiers. Each FB pin is tied to a resistive divider between its

output and ground to set the channel output voltage.

2, 7

BOOST1,

BOOST2

Supply pins to the power transistor drivers. Tie to external diode-capacitor charge pumps to

3, 6

SW1, SW2

Emitters of the internal power NPN transistors. Each SW pin is connected to the corresponding

inductor, freewheeling diode and bootstrap capacitor.

4, 5

PVIN1, PVIN2

Collectors of the internal power transistors and the power supplies to the corresponding current

sensing circuits. Pins 4 and 5 are not internally connected. They must be joined on the PCB and

closely bypassed to the power ground plane.

9, 16

COMP1,

COMP2

Outputs of the internal error amplifiers. The voltages at these pins control the peak switch

currents. RC networks at these pins stabilize the control loops. Pulling either pin below 0.7V

stops the corresponding switching regulator.

10, 14

SS1, SS2

A capacitor from either SS pin to ground provides soft-start and overload hiccup functions for

that channel. Pulling either SS pin below 0.8V with an open drain or collector transistor shuts off

the corresponding regulator. To completely shut off the SC2620 to low-current state, pull both SS

pins to ground. Soft-start is recommended for all applications.

11

GND

Analog ground. Connect to the PCB power ground plane at a single point.

12

VIN

Power supply to the analog control section of the SC2620. Connect to the PVIN pins through an

optional RC filter.

13

ROSC

An external resistor between this pin and the analog ground sets the channel switching frequency.

15

PGOOD1

Open collector output of Channel 1 power good comparator. Tie to an external pull-up resistor

from the input or the output of the converter. PGOOD1 output becomes valid as soon as V

above 1 V

10% of its final regulation voltage.

Underside

Metal

The exposed pad at the bottom of the package is electrically connected to the ground pin of the

SC2620. It also serves as a thermal contact to the circuit board. It is to be soldered to the analog

ground plane of the PC board.

Pin Descriptions

Part Number

Package

SOIC-16 EDP

SC2620EVB

Evaluation Board

Notes:

(1) Only available in tape and reel packaging. A reel contains

2500 devices.

(2) Lead free product. This product is fully WEEE and RoHS

compliant.

1

2

3

4

5

6

7

8

FB1

BOOST1

TOP VIEW

(16 Pin SOIC-EDP)

13

12

14

15

16

11

10

9

COMP1

SW1

PGOOD1

PVIN1

SS1

GND

SS2

ROSC

VIN

COMP2

SW2

FB2

BOOST2

PVIN2