MAX1577ZEVKIT Maxim Integrated, MAX1577ZEVKIT Datasheet - Page 2

• Manufacturer Part Number: MAX1577ZEVKIT
• Description: Charge Pumps Evaluation Kit for the MAX1577Y MAX1577Z
• Manufacturer: Maxim Integrated

Specifications of MAX1577ZEVKIT

• Function: Step Up, Step Down
• Output Voltage: 3.4 V, 4.6 V, 5.1 V
• Output Current: 1200 mA

•
Follow the steps below to verify board operation:
1)
2)
3)
4)
5)
6)
7)
8)
9)
MAX1577Z Evaluation Kit
Table 1. Jumper Descriptions
2
JUMPER
_______________________________________________________________________________________
JU1
JU2
JU3
JU4
2.7V to 5.5V power supply or battery capable of
delivering 2.5A
Verify that shunts are connected across pins 1-2
of jumpers JU1, JU2, and JU3.
Preset the power supply to 4.2V.
Turn off the power supply. Do not turn on the
power supply until all connections are com-
pleted.
Connect the positive power-supply terminal to the
pad on the EV kit labeled IN.
Connect the power-supply ground terminal to the
pad on the EV kit labeled GND.
Turn on the power supply. The LED will flash once
due to the on-board pulse generator circuit power-
ing up.
Press the button to flash the LED at 1.1A. The pulse
generator limits the flash duration to approximately
125ms.
Move jumper JU2 to short pins 2-3 (selects movie
mode).
Verify that the LED is lit.
EN1 connects to the output of
the on-board pulse generator.
EN2 connects to the output of
the on-board pulse generator.
Connects power to the on-
board pulse generator.
JU4 is shorted on the PC board and connects the white LED to
the output of the MAX1577Z.
SHORT 1-2
Recommended Equipment
Quick Start
EN2 connects to IN for movie
mode.
Procedure
SHORT 2-3
N/A
N/A
The LED current is adjusted by changing the resistor
R1. Calculate the value of R1 with the following equa-
tion, where I
brightness:
For more information on setting the brightness, refer to
the MAX1577Y/MAX1577Z data sheet.
The MAX1577Z has two inputs for selecting 100%,
33%, and 20% output current, or shutdown. Using JU1
and JU2 (see Table 1), these inputs can be connected
to the output of the on-board pulse generator for a
strobed output, while EN2 can be connected to IN for
movie mode, pulled low, or driven from an external
pulse generator. With the default 100% current setting
(R1 = 0.27Ω), the selectable output currents are
described in Table 2.
Table 2. Default Output Currents
OPEN
JU1
1-2
Adjusting the 100% Brightness Level
EN1 is pulled low by a 100kΩ resistor. EN1 can be
driven from an external pulse generator connected
to the EN1 pad on the left side of the EV kit.
EN2 is pulled low by a 100kΩ resistor. EN2 can be
driven from an external pulse generator connected
to the EN2 pad on the left side of the EV kit.
Power to the on-board pulse generator is
disconnected. Leave JU3 open when measuring
the quiescent current of the MAX1577Z.
Cut the trace shorting JU4 to use an external LED,
or when operating in voltage regulation mode.
OPEN
OPEN
OUT
JU2
1-2
2-3
1-2
2-3
is the output current in amps for 100%
R
Detailed Description
1
220mA Movie Mode/1100mA Flash
=
I
0 3 .
OUT
220mA Movie Mode
OPEN
V
1100mA Flash
367mA Flash
220mA Flash
FUNCTION
Shutdown
Control Inputs