Evaluates: MAX8516/MAX8517/MAX8518
MAX8517 Evaluation Kit
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Quick Start
Recommended Equipment
Before beginning, the following equipment is needed:
• One 4V, 1A variable-output power supply
• Dummy load capable of sinking 1A
• Digital multimeter (DMM)
Procedure
The MAX8517 EV kit is fully assembled and tested.
Follow the steps below to verify board operation.
Caution: Do not turn on power supplies until all con-
nections are completed.
1) Preset the power supply to 1.425V and turn off the
power supply.
2) Verify that a shunt is across pins 1-2 of JU1 to
enable the device.
3) Connect the positive lead of the power supply to
the VIN pad on the EV kit, and the negative lead of
the power supply to the GND pad on the EV kit.
4) Connect the positive input of the DMM to the VOUT
pad on the EV kit, and the negative input of the
DMM to the GND pad on the EV kit to measure the
output voltage.
5) Turn on the power supply and verify that the output
voltage is 1.2V ±1.4%.
6) Sweep the input voltage from 1.425V to 3.6V. Verify
that the output voltage is 1.2V ±1.4% over the entire
input range.
7) Set the power supply to 2V.
8) Connect the 1A load between the VOUT and GND
pads on the EV kit.
9) Verify that the output voltage is 1.2V ±1.4%.
Detailed Description of Hardware
Output Voltage Selection
The MAX8516/MAX8517/MAX8518 feature an
adjustable output voltage from 0.5V to 3.4V, using two
external resistors connected as a voltage-divider to FB,
as shown in Figure 1. The output voltage is set by the
following equation:
where V
FB
is 0.5V. Choose R2 < 1kΩ to optimize quies-
cent current, accuracy, and high-frequency power-sup-
ply rejection. To simplify resistor selection:
Shutdown Mode
The MAX8517 EV kit features 3-pin jumper JU1 to con-
trol the enable (EN) input. For normal operation, con-
nect EN to IN by placing a shunt across pins 1-2. To
shut down the device, pull EN to GND by placing a
shunt across pins 2-3. During shutdown, an internal
10kΩ resistor pulls down the output.
Power-OK (POK) (MAX8517 Only)
The MAX8517 EV kit features a power-OK (POK) output
to indicate the status of the output. The 100kΩ pullup
resistor (R4) pulls POK high when the regulator output
is within ±10% of its nominal output voltage. If the out-
put voltage falls or rises outside this range, POK transi-
tions low.
Power-On Reset (POR) (MAX8518 Only)
The EV kit can also evaluate the MAX8518 IC, which
features a power-on-reset output that transitions high
150ms (typ) after the output has risen above 90% of its
final value. If the part is in shutdown mode, falls below
90% of the nominal output voltage, or experiences a
short-circuit/thermal fault, POR immediately transitions
low. This open-drain output requires an external pullup
resistor to IN. Connect POR to IN by installing a 100kΩ
pullup resistor (R3).
