MAX1844EVKIT Maxim Integrated, MAX1844EVKIT Datasheet - Page 2

• Manufacturer Part Number: MAX1844EVKIT
• Description: Power Management IC Development Tools
• Manufacturer: Maxim Integrated
• Series: MAX1844r

• 7V to 24V power supply, battery, or notebook AC
• DC bias power supply, 5V at 100mA
• Dummy load capable of sinking 4A
• Digital multimeter (DMM)
• 100MHz dual-trace oscilloscope
1) Ensure that the circuit is connected correctly to the
2) Verify that the shunts are across JU1, JU2, JU9 pins
3) Turn on battery power prior to +5V bias power; oth-
4) Observe the 1.8V output with the DMM and/or oscil-
The EV kit output is preset to +1.8V. If a 2.5V output is
desired, cut the trace shorting JU7 and install a short
across R2.
MAX1844 Evaluation Kit
2
Note: Please indicate that you are using the MAX1844 when
contacting these component suppliers.
Central Semiconductor
Dale
Fairchild
IR
IRC
Nihon
Sanyo
Sumida
Taiyo Yuden
TDK
adapter
supplies and dummy load prior to applying any
power.
1 and 2, and JU10 pins 2 and 3.
erwise, the output UVLO timer will time out and the
FAULT latch will be set, disabling the regulator until
+5V power is cycled or shutdown is toggled.
loscope. Look at the LX switching-node and MOS-
FET gate-drive signals while varying the load current.
_______________________________________________________________________________________
SUPPLIER
Evaluating Other Output Voltages
Component Suppliers
Detailed Description
516-435-1110
402-564-3131
408-721-2181
310-322-3331
361-992-7900
847-843-7500
619-661-6835
708-956-0666
408-573-4150
847-390-4373
Equipment Needed
PHONE
Quick Start
516-435-1824
402-563-6296
408-721-1635
310-252-7175
361-992-3377
847-843-2798
619-661-1055
708-956-0702
408-573-4159
847-390-4428
FAX
The output voltage can also be adjusted between 1.0V
and 5.5V by selecting R1 and R2 values. Cut the PC
board trace shorting JU7, then select feedback resistor
R2 in the 5kΩ to 50kΩ range. R1 is then given by:
where V
mizing components for output voltage selection.
Table 1. Jumper JU1 Functions
(Shutdown Mode)
Table 2. Jumper JU2 Functions
(Low-Noise Mode)
Table 3. Jumper JU3 Functions
(Fixed/Adjustable Current-Limit Selection)
LOCATION
LOCATION
LOCATION
SHUNT
SHUNT
SHUNT
OFF
OFF
OFF
ON
ON
ON
FB
= 1.0V. See MAX1844 data sheet for opti-
R1 = R2 ((V
(remove R3/R9 divider)
through voltage-divider
R3/R9. Refer to the
Current-Limit Circuit
section in the MAX1844
data sheet for
information on selecting
R3/R9.
Connected to VCC,
Connected to REF
Connected to VCC
Connected to GND
Connected to VCC
Connected to GND
SHDN/PIN
SKIP/PIN
ILIM PIN
OUT
Jumper Settings
/ V
FB
Low-noise mode,
forced fixed-frequency
PWM operation.
Normal operation,
allows automatic
PWM/PFM switchover
for pulse skipping at
light load, resulting in
highest efficiency.
MAX1844 enabled
Shutdown mode,
V
) - 1)
OUT
OPERATIONAL
Adjustable from
25mV to 200mV.
Programmed for
65mV by R3 and
R9.
CURRENT-LIMIT
THRESHOLD
= 0
MAX1844
OUTPUT
MODE
100mV