High-Voltage Switch Control (CTL)

Jumper JU2 configures the positions of the high-

voltage switch control pin (CTL) of the MAX17075 IC.

The CTL pin can be controlled by an external logic con-

troller connected to the EV kit’s CTL pad. Remove the

shunt from jumper JU2 before connecting an

external controller to the CTL pad. See Table 2 for JU2

shunt positions.

High-Voltage Switch Output (VGON)

Dummy Load

The MAX17075 EV kit features a capacitive dummy

load of 1500pF (C18) at the VGON output pad to simu-

late a TFT panel load to test the switch array. When

testing with an actual LCD panel, disconnect the

dummy load. Jumper JU3 connects and disconnects

the dummy load. Table 3 lists the selectable JU3

jumper options.

Output-Voltage Selection

Step-Up Switching Regulator Output Voltage

(AVDD)

The MAX17075 EV kit’s step-up switching-regulator out-

put (AVDD) is set to +13V by feedback resistors R8 and

R9. To generate output voltages other than +13V (up to

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

Operation at significantly higher output voltages could

reduce the available output current, and require

changes in component values or voltage rating for

capacitors C3 and C4. Refer to the

Design Procedure,

Step-Up Regulator, Output-Voltage Selection section in

the MAX17075 IC data sheet for instructions on select-

ing resistors R8 and R9.

Positive Charge-Pump Output (SRC)

The positive charge-pump output (SRC) is set to +30V

by voltage-divider resistors R15 and R16. To set SRC to

other voltages (up to approximately 3xAVDD, limited to

+36V), select different voltage-divider resistors. Refer to

the

Design Procedure, Charge-Pump Regulators,

Output-Voltage Selection section in the MAX17075 IC

data sheet for instructions on selecting resistors R15

and R16.

Negative Charge-Pump Output (VGOFF)

The negative charge-pump output (VGOFF) is set to

-7V by voltage-divider resistors R6 and R7. To set

VGOFF to other voltages (from 0 to -AVDD approxi-

mately), select different voltage-divider resistors. Refer

to the

Design Procedure, Charge-Pump Regulators,

Output-Voltage Selection section in the MAX17075 IC

data sheet for instructions on selecting resistors R6 and

R7.

Op-Amp Output (OUT)

The op-amp output (OUT) is set to +6.5V by voltage-

divider resistors R3 and R4. To set the outputs to other

voltages (from 0 to AVDD), select different voltage-

divider resistors.

MAX17075 Evaluation Kit

4

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Table 2. JU2 Jumper Selection (CTL)

SHUNT POSITION

CTL PIN CONNECTED TO

HIGH-VOLTAGE SWITCH CONFIGURATION

Installed

VIN

COM pin connected to SRC pin

COM pin disconnected from DRN pin

Not installed*

GND through resistor R5

COM pin connected to DRN pin

COM pin disconnected from SRC pin

None

External logic controller

through the CTL pad

CTL driven by external logic controller

CTL high: COM pin connected to SRC pin

CTL low: COM pin connected to DRN pin

*

Default position.

Table 3. JU3 Jumper Selection (C18)

SHUNT POSITION

VGON

OPERATION

Installed

Connected to C18

Dummy load testing

Not installed*

Not connected to C18

Normal operation, no load

*

Default position.