MAX8795A Evaluation Kit

4

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Output Voltage Selection

Step-Up Switching-Regulator

Output Voltage (VMAIN)

The MAX8795A EV kit’s step-up switching-regulator

output, limited by the built-in 20V n-channel MOSFET, is

set to +14V through feedback resistors R1 and R2. To

+18V), select different external voltage-divider resistors

(R1 or R2). Refer to the

Output-Voltage Selection sec-

tion in the MAX8795A IC data sheet for instructions on

selecting the feedback resistors.

Positive Linear-Regulator

Output Voltage (VPOS)

The MAX8795A EV kit’s positive linear-regulator output

is set to +25V by feedback resistors R3 and R4. To

generate output voltages other than +25V (+1.25V to

nearly the positive charge-pump output voltage), select

different external voltage-divider resistors (R3 or R4).

Refer to the

Output-Voltage Selection section in the

MAX8795A IC data sheet for instructions on selecting

the resistors.

Negative Linear-Regulator

Output Voltage (VNEG)

The MAX8795A EV kit’s negative linear-regulator output

is set to -10V by feedback resistors R7 and R8. To gen-

erate output voltages other than -10V (0 to nearly the

negative charge-pump output), select different external

voltage-divider resistors (R7 or R8). Refer to the

Output-Voltage Selection section in the MAX8795A IC

data sheet for instructions on selecting the resistors.

Op-Amp Output Voltages (OUT1–OUT5)

The MAX8795A EV kit’s op amps (OUT1–OUT5) are

designed to drive the LCD backplane. Using external

voltage-divider resistors, each op amp is configured to

one-half of VMAIN’s output voltage. To generate output

voltages other than +7V, select different external volt-

age-divider resistors (R11–R20).