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Maxim Integrated

Evaluates: MAX16833/MAX16833B

MAX16833 Evaluation Kit

Detailed Description of Hardware

The MAX16833 EV kit provides a proven design to evalu-

ate the MAX16833 high-voltage HB LED driver with inte-

grated high-side current sense. The EV kit is set up for

boost and buck-boost configurations and operates from

a 5V to 18V DC supply voltage. The EV kit is configured

to deliver up to 1A to a series LED string. The string for-

ward voltage can vary from 3V to 36V.

Analog Dimming Control (ICTRL)

When JU1 is installed, the ICTRL pin is connected to the

voltage-divider of R7 and R8, which sets the voltage at

using the following formula:

LED

200mV

I

R4

=

Alternatively, the analog dimming can be controlled

by removing the shunt of JU1 and applying a voltage

between 0 and 5.5V on the ICTRL pad of the EV kit.

Pulse-Dimming Input (PWMDIM)

Pulse dimming can be achieved by applying a pulsating

voltage source on the PWMDIM pad of the EV kit. When

PWMDIM is pulled low, DIMOUT is pulled high and the

pulse-width modulated (PWM) switching is disabled.

Frequency Dithering (LFRAMP)

When JU3 is in the 2-3 position and JU2 is not installed,

frequency dithering is achieved.

Frequency Synchronization (RT/SYNC)

The devices can be synchronized to an external clock

by applying a synchronizing pulse on the RT/SYNC

input pin. Refer to the MAX16833/MAX16833B IC data

sheet for more information regarding synchronizing to an

external clock. Frequency dithering must be disabled for

external frequency synchronization.

Evaluating the MAX16833B

For evaluating the MAX16833B, replace the MAX16833

on the EV kit with a MAX16833B. The jumper configura-

tions are as follows: JU1 (open shunt position), JU2 (1-2

shunt position), JU3 (1-2 shunt position). See Table 1 for

details.