SC644

0

Pin Descriptions

Pin #

Pin Name

Pin Function



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

BL

Current sink output for backlight LED  — 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

BL6

Current sink output for backlight LED 6 — leave this pin open if unused

9

AGND

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

0

LDO4

Output of LDO4



LDO3

Output of LDO3

2

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)

3

BYP

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

4

LDO2

Output of LDO2

5

LDO

Output of LDO

6

OUT

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

7

C2+

Positive connection to bucket capacitor 2

8

C+

Positive connection to bucket capacitor 

9

C-

Negative connection to bucket capacitor 

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