SC643

10

Pin Descriptions

Pin #

Pin Name

Pin Function

1

IN

Battery voltage input

2

PGND

Ground pin for high current charge pump

3

BL3

Current sink output for backlight LED 3 — leave this pin open if unused

4

BL2

Current sink output for backlight LED 2 — leave this pin open if unused

5

BL1

Current sink output for backlight LED 1 — leave this pin open if unused

6

BL4

Current sink output for backlight LED 4 — leave this pin open if unused

7

BL5

Current sink output for backlight LED 5 — leave this pin open if unused

8

ENL4

Enable pin for LDO4 — active high. See LDO4 Control Register Section and Programmable LDO

Outputs Section to determine how to use this pin.

9

AGND

Analog ground pin — connect to ground and separate from PGND current

10

LDO4

Output of LDO4

11

LDO3

Output of LDO3

12

SPIF

SemPulse single wire interface pin — used to enable/disable the device and to configure all regis-

ters (refer to Register Map and SemPulse Interface sections)

13

BYP

Bypass pin for LDO reference — connect a 22nF ceramic capacitor to AGND

14

LDO2

Output of LDO2

15

LDO1

Output of LDO1

16

OUT

Charge pump output — all LED anode pins should be connected to this pin

17

C2+

Positive connection to bucket capacitor 2

18

C1+

Positive connection to bucket capacitor 1

19

C1-

Negative connection to bucket capacitor 1

20

C2-

Negative connection to bucket capacitor 2

T

THERMAL PAD

Thermal pad for heatsinking purposes — connect to ground plane using multiple vias — not con-

nected internally