Maxim Integrated MAX16836 Evaluation Kit MAX16836EVKIT+ MAX16836EVKIT+ 数据表

产品代码
MAX16836EVKIT+
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页码 4
Evaluates:  MAX16835/MAX16836
MAX16836 Evaluation Kit
2
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Quick Start
Recommended Equipment
Before beginning, the following equipment is needed:
• 0 to 30V or above, 0.5A power supply
Procedure
The MAX16836 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) Connect a DC power supply (0 to 30V or above,
0.5A) to VIN.
2) Verify that a shunt is not installed across jumper
JU1 to enable U1.
3) Verify that a shunt is installed across pins 1-2 of
jumper JU2 to select 350mA output current.
4) Connect a 350mA-rated LED between LED+ and
LED-.
5) Turn on the power supply and increase the input
voltage to above 6.5V. The LED should glow with
full brightness. Measure the LED current, which
should be 350mA 
±3.5%.
6) Increase the supply voltage and measure the LED
current, which should be 350mA 
±3.5%. Note that
the maximum voltage drop between IN and OUT
should be ~7V to limit the maximum power dissipa-
tion to approximately 2.5W.
7) Measure the voltage across V5, which should be 
5V 
±4%.
Detailed Description of Hardware
The MAX16836 EV kit demonstrates a high-output-
current LED driver with accurate current control based
on the MAX16836 current regulator. The MAX16836 EV
kit is capable of supplying regulated output currents of
up to 350mA and runs at supply voltages between
6.5V to 40V. If the supply voltage is above the LED
operating voltage by more than 7V, the maximum out-
put current should be limited to prevent the device
from entering into thermal shutdown due to excessive
power dissipation.
The MAX16836 EV kit features PWM dimming to control
the LED brightness by varying the duty cycle of the
PWM input signal. Users can select between three lev-
els of output LED currents by setting jumper JU2 (see
Table 1 for jumper settings). The MAX16836 EV kit also
includes a connection for the 5V regulated output and
access to the on-board current-sense resistor.
Output Current Setting
The output current can be adjusted by replacing resis-
tors R2 or R3 with values calculated using the following
equation:
where R
SENSE
is the external current-sense resistance
between CS+ and GND, I
LED
is the desired output cur-
rent, and V
SENSE
is 200mV (typ).
PWM Dimming
The PWM dimming controls the LED brightness by
adjusting the duty cycle of the PWM input signal con-
nected to the DIM input. A high at the DIM input turns
on the output current and a low turns off the output cur-
rent. Connect a signal with peak amplitude between 5V
and 40V, frequency between 100Hz and 2kHz, and
vary the duty cycle to adjust the LED brightness. LED
brightness increases when duty cycle increases and
vice versa. Duty cycle can be as low as 10% even at a
PWM frequency of 2kHz.
5V Regulated Output
The 5V regulator can be used to power other compo-
nents from the V5 test point. The 5V output supplies up
to 4mA of current.
Jumper Selection
Two-pin jumper JU1 controls the EN pin of the
MAX16836 and enables or disables the device. Three-
pin jumper JU2 selects between three different output
current settings. Table 1 lists the jumper options.
R
SENSE
=
V
I
SENSE
LED
SHUNT POSITION AND FUNCTION
JUMPER
1-2 (installed)
2-3
Open
JU1
U1 disabled
U1 enabled*
JU2
350mA*
250mA
150mA
Table 1. Jumper JU1 and JU2 Functions
*
Default position.