Detailed Description - Analog Devices MAX17553C EV Kit A Manual

Evaluates: MAX17553 (MAX17553C)

Detailed Description

The MAX17553C EV kit provides a proven design to evaluate the MAX17553C, a 4V to 60V, 50mA ultra-small, high
efficiency, synchronous step-down DC-DC converter. The EV kit comes with installed components for delivering 12V,
50mA (max) output current from a 14V to 60V input. The EV kit can be used to verify the EN/UV and HYST features of
the MAX17553C. The EV kit is programmed to switch at a fixed frequency of 400kHz. The EV kit can be programmed to
switch at different frequency with an appropriate output inductor (L1) and an output capacitor (C6). The EV kit can also
be used to verify the output overload or short circuit protection as well as the thermal shutdown protection. Refer to the
MAX17553C IC data sheet to change the EV kit configuration to a different specification.
Setting the Input EN/UV Level with HYST
The device offers an adjustable input undervoltage and adjustable hysteresis levels. Set the voltage at which the device
turns on and turns off with a resistor network connected between IN, EN/UV, HYST, and GND pins (see
R1 to be 3.32MΩ (max), then calculate R2 and R3 as follows:
where V and V
IN(ON) IN(OFF)
the MAX17553 IC data sheet for more information.
Figure 2. Setting the Input Undervoltage Level with Hysteresis
Adjusting the Output Voltage
The output voltage of MAX17553C can be programmed from 0.8V to 0.9 x V
feedback divider from output to GND (see
less than or equal to 100kΩ and calculate R
Figure 3. Setting the Output Voltage
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R2 =
R3 =
(V
IN(ON)
are the voltages at which the device is required to turn on and turn off respectively. Refer to
V
IN
R1
R2
Figure 3). Connect the center node of the divider to the FB pin. Choose R
with the following equation:
U
R
U
MAX17553C
V × R1
ENF
(V − V )
IN(OFF) ENF
V × R1 × R2
ENR
× ( R1 + R2 ) )
× R2 − V
ENR
IN
EN/UV
R3
HYST
IN
V
OUT
= R × [ − 1]
B
0.8
V
OUT
R
U
FB/VO
R
B
MAX17553C Evaluation
. Set the output voltage by using a resistive
Kit
Figure 2). Choose
B
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