Datasheet

MAX17113 Evaluation Kit
Evaluates: MAX17113
4 ______________________________________________________________________________________
Step-Up Regulator Output-Voltage
Selection (AVDD)
The output voltage (VIN to 18V) of the main step-up
regulator is set by connecting a resistive voltage-divider
from the output (AVDD) to AGND with the center tap con-
nected to FB1. Calculate R3 with the following equation:
AVDD
FB1
V
R3 R4 1
V
 
= × −
 
 
where V
FB1
, the step-up regulator’s feedback set point,
is 1.25V.
Positive Charge-Pump Output
Output-Voltage Selection (VGON)
The positive charge-pump output (VGON) is set to +35V
by voltage-divider resistors R16 and R17. To set VGON
to other voltages (up to approximately 3 x AVDD, 44V
max), select different divider resistors. For voltages
below 2 x AVDD, change the shunt position of JU7 to
1-2. Refer to the Design Procedure, Charge-Pump
Regulators, Output-Voltage Selection section in the
MAX17113 IC data sheet for instructions on selecting
resistors R16 and R17.
Negative Charge-Pump Output
Output-Voltage Selection (VGOFF)
The negative charge-pump output (VGOFF) is set to -6V
by voltage-divider resistors R1 and R2. To set VGOFF
to other voltages (0V to -VIN), select different divider
resistors. For VGOFF less than -16V, select C15 with a
higher voltage rating. Refer to the Design Procedure,
Charge-Pump Regulators, Output-Voltage Selection sec-
tion in the MAX17113 IC data sheet for instructions on
selecting resistors R1 and R2.
Jumper Selection
Several jumper settings in the following tables illustrate
features of the MAX17113 EV kit.
Frequency Select Input (FSEL)
The MAX17113 EV kit features jumper JU1 to control
the switching regulator’s operating frequency. Connect
FSEL to AGND for 450kHz operation. Connect FSEL to
VL for 600kHz operation. See Table 2 for jumper JU1
functions.
High-Voltage Switch Mode (MODE)
The MAX17113 EV kit features an option to select the
operating mode (delay or no delay) for the high-voltage
switches. On the rising edge of the CTL pin, GON con-
nects to SRC. On CTL’s falling edge, GON may connect
immediately to DRN (no delay), or to DRN after a delay
set by C9. Refer to the High-Voltage Switch Control sec-
tion in the MAX17113 IC data sheet for a more detailed
description of the two modes of operation. Jumper JU2
selects the high-voltage switch operating mode for the
MAX17113. Table 3 lists the selectable JU2 jumper
options.
*Default position.
*Default position.
X = Don’t care.
*Default position.
Table 2. Jumper JU1 Functions
Table 4. Jumper JU3 and JU4 Functions
Table 3. Jumper JU2 Functions
SHUNT
POSITION
FSEL PIN
OPERATION OF
FREQUENCY (kHz)
Installed Connected to VL 600
Not
installed*
Connected to AGND
(through internal 1MI
pulldown resistor)
450
SHUNT POSITION
STEP-DOWN AND NEGATIVE
CHARGE-PUMP REGULATOR
STEP-UP AND POSITIVE
CHARGE-PUMP REGULATOR
JU3 JU4
Installed* Installed* Enabled Enabled
Installed Not installed Enabled Disabled
Not installed X Disabled Disabled
SHUNT
POSITION
MODE PIN
HIGH-VOLTAGE
SWITCH MODE
1-2 Connected to C9 Delay set by C9
2-3* Connected to VL No delay
Not installed Unconnected Not allowed