MAX17114 Evaluation Kit

4 ______________________________________________________________________________________

High-Voltage Switch-Control Block

Timing-Control Input Supply (JU3)

The MAX17114’s high-voltage switch-control block is

controlled by GVOFF and XAO. XAO is pulled to VL by

default and jumper JU3 controls GVOFF. When JU3 is

set high, VGHM is connected to VGH. When GVOFF

is set low, VGHM is connected to DRN. When XAO is

triggered, VGHM pulls high to facilitate discharge to the

panel until there’s enough voltage on the VGH pin. See

Table 3 for jumper JU3 configuration.

Step-Down Regulator Output Mode (JU4)

Jumper JU4 controls the output mode of the step-down

regulator (OUT). When a shunt is not installed across

JU4, the FB2 pin is pulled to GND through R18 and the

regulator provides a fixed +3.3V output. When a shunt

is installed across JU4, the FB2 pin is connected to the

center of a resistive voltage-divider between OUT and

GND to set the voltage at OUT. See Table 4 for jumper

JU4 configuration.

Enable Input EN (JU5)

The MAX17114’s enable input can be configured through

jumper JU5. When EN is high, the step-up regulator and

positive charge pump are enabled. When EN is low, the

step-up regulator and positive charge pump are dis-

abled. See Table 5 for jumper JU5 configuration.

Soft-Start Input Capacitance (JU6)

The MAX17114’s soft-start function can be done inter-

nally, when the capacitance on the SS pin is < 200pF, or

externally, when capacitance on the SS pin is > 200pF.

Jumper JU6 controls the soft-start function by giving the

option to connect a 0.1FF capacitor (C27) to the SS pin.

When a shunt is installed across JU6, C27 is connected

and the soft-start time can be calculated at ~25ms.

When there is not a shunt across JU6, the soft-start func-

tion is carried out internally at ~12ms. See Table 6 for

jumper JU6 configuration.

Output-Voltage Selection

The MAX17114 EV kit’s step-up switching-regulator

output (AVDD) is set to +16V by feedback resistors R3

and R4. To generate output voltages other than +16V,

select different external voltage-divider resistors, R3

and R4. Refer to the Step-Up Regulator, Output-Voltage

Selection section in the MAX17114 IC data sheet for

more information.

*Default position.

*Default position.

*Default position.

*Default position.

Table 3. Jumper JU3 Function

Table 5. Jumper JU5 Functions

Table 4. Jumper JU4 Function

Table 6. Jumper JU6 Functions

SHUNT

POSITION

GVOFF PIN

VGHM OUTPUT

1-2

Connected to VL

VGHM connected

to VGH

2-3*

Connected to GND

VGHM connected

to DRN

SHUNT

POSITION

FB2 PIN

STEP-DOWN

OUTPUT MODE

Installed

Connected to center of a

resistive voltage-divider

between R17 and R18

Adjustable mode

Not

installed*

Connected to GND

through R18

Fixed 3.3V mode

SHUNT

POSITION

EN PIN

AVDD, VGON

OUTPUTS

1-2*

Connected to VIN

Enabled

2-3

Connected to GND

Disabled

SHUNT

POSITION

SOFT START

CAPACITANCE

SOFT START

TIME

Installed

External

25ms

Not

Installed

Internal

12ms