Analog Integrated Circuit Device Data

Freescale Semiconductor

3

34702

PIN CONNECTIONS

PIN CONNECTIONS

Figure 3. Pin Connections

Table 1.

Pin Function Description

A functional description of each pin can be found in the Functional Pin Description section beginning on page 16.

Pin

Pin Name

Formal Name

Definition

1

FREQ

Oscillator Frequency

This switcher frequency selection pin can be adjusted by connecting external

resistor R

tied to V

2

INV

Inverting Input

Buck controller error amplifier inverting input.

3

VOUT

Output Voltage

Output voltage of the buck converter. Input pin of the switching regulator power

sequence control circuit.

4, 5

VIN2

Input Voltage 2

Buck regulator power input. Drain of the high side power MOSFET.

6, 7

SW

Switch

Buck regulator switching node. This pin is connected to the inductor.

8, 9

24, 25

GND

Ground

Analog ground of the IC, thermal heatsinking.

10, 11

PGND

Power Ground

Buck regulator power ground.

12

VBD

Boost Drain

Drain of the internal boost regulator power MOSFET.

13

VBST

Boost Voltage

Internal boost regulator output voltage. The internal boost regulator provides a 20mA

output current to supply the drive circuits for the integrated power MOSFETs and the

external N-channel power MOSFET of the linear regulator. The voltage at the V

BST

pin is 7.75V nominal.

14

BOOT

Bootstrap

Bootstrap capacitor input.

15

SDA

Serial Data

16

SCL

Serial Clock

17

LCMP

Linear Compensation

Linear regulator compensation pin.

18

LFB

Linear Feedback

Linear regulator feedback pin.

19

LDO

Linear Regulator

Input pin of the linear regulator power sequence control circuit.

CLKSYN

1

EN2

EN1

ADDR

GND

GND

V

DD1

V

IN1

LDRV

CS

LFB

LCMP

LDO

RT

CLKSEL

RST

FREQ

V

IN2

SW

SW

GND

GND

PGND

PGND

VBD

VBST

SDA

SCL

BOOT

V

IN2

INV

V

OUT

8

9

10

11

12

13

14

15

16

3

4

5

6

7

2

32

25

24

23

22

21

20

19

18

17

30

29

28

27

26

31