MAX1620/MAX1621
Digitally Adjustable LCD Bias Supplies
8 _______________________________________________________________________________________
External Transistor Drive, HighDHI1616
External Transistor Drive, LowDLO1515
Switching-Voltage Sense InputLX1414
Power GroundPGND1313
Analog GroundAGND1212
IC Input Supply, 3.0V to 5.5VV
DD
1111
DAC Output Voltage
Logic-Level Shutdown Input (active-low)
System Management Bus Suspend-Mode Input (active-low)
Power OK Voltage-Sense Input, 1V threshold
Reference Voltage Output. Bypass REF with 0.1µF to AGND.
Logic-Level Input. POL selects output voltage polarity: high = positive boost,
low = negative boost.
Logic-Level Input. A rising edge on UP increases V
OUT
.UP = DN = high resets
the counter to mid-scale.
DOUT
System Management Bus Serial-Clock Input
Battery Voltage-Sense Input
System Management Bus Serial-Data Input and Open-Drain Output
10
Logic-Level Input. A rising edge on DN decreases V
OUT
.UP = DN = high resets
the counter to mid-scale.
10
FUNCTION
SHDN
—4
SUS
4—
POK55
REF66
POL77
UP—2
Feedback Voltage InputFB9
SCL2—
BATT33
SDA1—
9
Open-Drain Output. LCDON controls LCD with external PNP.LCDON
8
DN—1
8
MAX1621MAX1620
NAME
PIN
______________________________________________________________Pin Description
