Coilcraft, Inc. 847-639-6400 www.coilcraft.com
Diodes, Inc. 805-446-4800 www.diodes.com
Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com
Note: Indicate that you are using the MAX15031 when contacting these component suppliers.
Quick Start
Required Equipment
Before beginning, the following equipment is needed:
• MAX15031 EV kit
• 2.9V to 5.5V, 1A DC power supply
• 0 to 5mA adjustable load rated for at least 76V
• Digital multimeter (DMM)
WARNING: Voltages exceeding 42V may exist on
the VOUT, APD, MOUT, and PGND PCB pads.
Procedure
The MAX15031 EV kit is fully assembled and tested.
Follow the steps below to verify board operation.
Caution: Do not turn on the power supply until all
connections are completed.
1) Verify that a shunt is installed on jumper JU1 (70V
output).
2) Verify that a shunt is installed on pins 1-2 of jumper
JU2 (enabled).
3) Connect the adjustable load to the APD and the
SGND pads.
4) Connect the power supply to the VIN pad and the
power-supply ground to the PGND pad.
5) Connect the DMM across the APD and SGND PCB
pads.
6) Turn on the power supply and set it to 3.3V.
7) Verify that the DMM reads approximately 70V.
Detailed Description of Hardware
The MAX15031 evaluation kit (EV kit) demonstrates the
MAX15031 in a small, 16-pin TQFN package with
internal power switch, current monitor, and adjustable
current-limiting circuit features. The circuit’s PWM
step-up DC-DC converter is designed for APD bias-
ing, switches at 400kHz, and is configured to deliver
approximately 70V and 0 to 4mA of current to the APD
output. The output voltage can be reconfigured from
VIN + 1V to 76V by replacing resistor R1 or adjusting
the CNTRL voltage. The EV kit demonstrates the
MAX15031’s APD fast current-limit, undervoltage lock-
out (UVLO), and thermal shutdown features.
The converter circuit’s PCB footprint is 8mm x 18mm.
The EV kit operates from a DC supply voltage of 2.9V to
5.5V and provides up to 4mA at the APD output.
The EV kit’s APD load simulator circuit is used for cur-
rent monitoring and step-response measurements. The
circuit is comprised of MOSFET N1, resistors R7, R8,
R9, and test points TP1, TP2, and TP3 (SGND). Test
point TP4 provides access to the MAX15031 BIAS
signal. Voltages exceeding 42V may exist on TP4.
Additionally, bulk capacitor C9 is provided in case long
connecting cables are used to power the EV kit during
lab evaluation. Capacitor C9 is not required in a typical
design.
SHDN
and Enable
The MAX15031 EV kit features a jumper to enable and
disable U1. Jumper JU2 will disable the EV kit when the
shunt is installed on pins 2-3. Installing the shunt on
pins 1-2 enables the EV kit. Refer to the
Shutdown
(SHDN)
section in the MAX15031 IC data sheet for
information. See Table 1 for jumper JU2 settings.
Table 1. SHDN and Enable (Jumper JU2)