MAX1856EVKIT Maxim Integrated, MAX1856EVKIT Datasheet - Page 2

• Manufacturer Part Number: MAX1856EVKIT
• Description: Power Management IC Development Tools Evaluation Kit for the MAX1856
• Manufacturer: Maxim Integrated
• Series: MAX1856r

MAX1856 Evaluation Kit
SLIC Power Supply
Note: Please indicate that you are using the MAX1856 when
contacting these component suppliers.
2
DESIGNATION
AVX
Central Semiconductor
Coiltronics
Dale Electronics Inc.
ICE Components
International Rectifier
IRC
Murata
Sanyo USA
Taiyo Yuden
_______________________________________________________________________________________
R2, R3
R4, R5
None
None
None
None
R10
R11
R12
R13
JU1
N1
U1
SUPPLIER
R1
R6
R7
R8
R9
Component List (continued)
QTY
1
1
0
2
1
1
1
1
1
1
1
0
1
1
1
1
1
1
Component Suppliers
DESCRIPTION
3.8A, 55V, N-channel MOSFET
(SOT223)
International Rectifier IRLL2705
200Ω ±5% resistor (2512)
Not installed
10Ω ±5% resistors (1206)
0.033Ω ±1% resistor (2010)
IRC LRC-LRF2010-01-R033-F or
Dale WSL 2010 0.033Ω 1%
100Ω ±5% resistor (0805)
200kΩ ±1% resistor (0805)
5.11kΩ ±1% resistor (0805)
681kΩ ±1% resistor (0805)
174kΩ ±1% resistor (0805)
100kΩ ±5% resistor (0805)
Not installed
MAX1856EUB (10-pin µMAX)
2-pin header
Shunt (JU1)
MAX1856 PC board
MAX1856 data sheet
MAX1856 EV kit data sheet
803-946-0690
631-435-1110
561-241-7876
650-526-8333
703-257-7740
310-322-3331
650-367-9000
814-237-1431
619-661-6835
408-573-4150
PHONE
803-626-3123
631-435-3388
561-241-9339
650-965-1644
703-257-7547
310-322-3332
650-367-7158
814-238-0490
619-661-1055
408-573-4159
FAX
The MAX1856 EV kit is fully assembled and tested.
Follow these steps to verify board operation. Do not turn
on the power supply until all connections are com-
pleted:
1) Verify that a shunt is across pins 1 and 2 of jumper
2) Connect a voltmeter to the VOUT1 pad.
3) Connect a +8V to +24V DC power supply to the VIN
4) Connect the supply ground to the GND pad.
5) Turn on the power supply and gradually increase
6) Verify that VOUT1 is -72V throughout the +8V to
7) Verify that VOUT2 is -24V throughout the +8V to
Note: Exercise caution when measuring the -72V.
For instructions on reconfiguring VOUT1 to -48V,
see Evaluating -48V Output.
The MAX1856 EV kit is an inverted flyback DC-DC con-
verter configured for two output voltages simultaneous-
ly. The transformer has a 1:2:2:2 turns ratio. The sec-
ondary has three taps to provide three different ratios of
1:2, 1:4, and 1:6. VOUT1 is connected to the 1:6 tap,
providing -72V, which can supply up to 100mA. VOUT2
is connected to the 1:2 tap, providing -24V, which can
supply up to 400mA. VOUT1 may be connected to the
1:4 tap to provide -48V and supply up to 200mA. The
input voltage can range from +8V to +24V. The output
voltage is determined by the following equation:
where (N2 / N1) is the secondary/primary turns ratio of
the transformer, and D is the duty cycle of the pulse-
width-modulating (PWM) switching signal.
For a fixed turns ratio, the duty cycle (D), will vary to
compensate for the variation in V
stant output voltage.
For example, for (N2 / N1) = 6:1, as V
to +24V, D will vary from 60% to 33% to keep V
constant at -72V.
JU1 (SYNC/SHDN).
pad, with the voltage set to 0.
the input voltage through the +8V to +24V range.
+24V input voltage range.
+24V input voltage range.
|
V
OUT
|
= V
IN
Output VOUT1 and VOUT2
Detailed Description
x (N2 / N1) x D/(1 - D)
IN
Quick Start
to maintain a con-
IN
varies from +8V
OUT