_______________General Description
The MAX742 DC-DC converter is a controller for dual-out-
put power supplies in the 3W to 60W range. Relying on
simple two-terminal inductors rather than transformers, the
MAX742 regulates both outputs independently to within
±4% over all conditions of line voltage, temperature, and
load current.
The MAX742 has high efficiency (up to 92%) over a wide
range of output loading. Two independent PWM current-
mode feedback loops provide tight regulation and opera-
tion free from subharmonic noise. The MAX742 can
operate at 100kHz or 200kHz, so it can be used with small
and lightweight external components. Also ripple and
noise are easy to filter. The MAX742 provides a regulated
output for inputs ranging from 4.2V to 10V (and higher with
additional components).
External power MOSFETs driven directly from the MAX742
are protected by cycle-by-cycle overcurrent sensing. The
MAX742 also features undervoltage lockout, thermal shut-
down, and programmable soft-start.
If 3W of load power or less is needed, refer to the MAX743
data sheet for a device with internal power MOSFETs.
________________________Applications
DC-DC Converter Module Replacement
Distributed Power Systems
Computer Peripherals
____________________________Features
Specs Guaranteed for In-Circuit Performance
Load Currents to ±2A
4.2V to 10V Input-Voltage Range
Switches From ±15V to ±12V Under Logic Control
±4% Output Tolerance Max Over Temp, Line,
and Load
90% Typ Efficiency
Low-Noise, Current-Mode Feedback
Cycle-by-Cycle Current Limiting
Undervoltage Lockout and Soft-Start
100kHz or 200kHz Operation
MAX742
Switch-Mode Regulator with
+5V to ±12V or ±15V Dual Output
________________________________________________________________
Maxim Integrated Products
1
MAX742
P
R
+5V
INPUT
S
-SENSE
-DRIVE
PWM
N
R
S
+SENSE
+DRIVE
-VO
+VO
PWM
OSC
+2.0V
VREF
CC+
CC-
__________Simplified Block Diagram
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
CSH+
CSL+
GND
EXT+
AV
AGND
CC+
FB+
TOP VIEW
PUMP
PDRV
EXT-
V+
SS
VREF
12/15
100/200
12
11
9
10
CSH-
CSL-
FB-
CC-
DIP/SO
MAX742
__________________Pin Configuration
19-3105; Rev 2; 8/96
PART
MAX742CPP
MAX742CWP
MAX742C/D 0°C to +70°C
0°C to +70°C
0°C to +70°C
TEMP. RANGE PIN-PACKAGE
20 Plastic DIP
20 Wide SO
Dice*
EVALUATION KIT MANUAL
FOLLOWS DATA SHEET
MAX742EWP
MAX742MJP -55°C to +125°C
-40°C to +85°C 20 Wide SO
20 CERDIP
MAX742EPP -40°C to +85°C 20 Plastic DIP
______________Ordering Information
* Contact factory for dice specifications
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800
MAX742
Switch-Mode Regulator with
+5V to ±12V or ±15V Dual Output
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 2, +4.5V < V+ < +5.5V.)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
V+, AV+ to AGND, GND.........................................-0.3V to +12V
PDRV to V+.............................................................+0.3V to -14V
FB+, FB- to GND..................................................................±25V
Input Voltage to GND
(CC+, CC-, CSH+, CSL+, CSH-, CSL-,
SS, 100/200
, 12/15)..................................-0.3V to (V+ + 0.3V)
Output Voltage to GND
(EXT+, PUMP) ..........................................-0.3V to (V+ + 0.3V)
EXT- to PDRV................................................-0.3V to (V+ + 0.3V)
Continuous Power Dissipation (any package)
up to +70°C.....................................................................500mW
derate above +70°C by ..........................................100mW/°C
Operating Temperature Ranges
MAX742C_ _ .......................................................0°C to +70°C
MAX742E_ _ ....................................................-40°C to +85°C
MAX742MJP ..................................................-55°C to +125°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10sec).............................+300°C
0mA < I
L
< 100mA,
12/15 = 0V
CONDITIONS
14.40 15.60
V
14.55 15.45
Output Voltage, ±15V Mode
(Notes 1, 2)
UNITSMIN TYP MAXSYMBOLPARAMETER
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
0mA < I
L
< 125mA,
12/15 = V+
11.52 12.48
V
11.64 12.36
Output Voltage, ±12V Mode
(Notes 1, 2)
No EXT- or PUMP load,
FB+ = FB- = open circuit
I
LOAD
= 0mA to 100mA
V+ = 4.5V to 5.5V, PDRV from PUMP
CSL+ = 0V, FB+ = open circuit
EXT+ or EXT-
100/200 = V+
100/200 = 0V
CSH- = V+, FB- = open circuit
CONDITIONS
mV150 225 300
Negative Current-Limit Threshold
(CSH- to CSL-)
mA
3
No-Load Supply Current
mV30 100
%/%0.01 0.05Line Regulation
Load Regulation (Note 2)
mV150 225 300
Positive Current-Limit Threshold
(CSH+ to CSL+)
%85 90Duty-Cycle Limit (Note 3)
kHzf
OSC
/2PUMP Frequency
kHz
75 100 125
V3.8 4.2UVLOUndervoltage Lockout
V0.2Undervoltage Lockout Hysteresis
V2.0Reference Output Voltage
170 200 230
f
OSC
Oscillator Frequency
UNITSMIN TYP MAXSYMBOLPARAMETER
V+ = 5V
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 2, V+ = 5V, 100/200 = 12/15 = 0V; T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
10V+ = 10V
MAX742
Switch-Mode Regulator with
+5V to ±12V or ±15V Dual Output
_______________________________________________________________________________________ 3
Note 1: Devices are 100% tested to these limits under 0mA to 100mA and to 125mA conditions using automatic test equipment.
The ability to drive loads up to 1A is guaranteed by the current-limit threshold, output swing, and the output current
source/sink tests. See Figures 2 and 3.
Note 2: Actual load capability of the circuit of Figure 2 is ±200mA in ±15V mode and ±250mA in ±12V mode. Load regulation is
tested at lower limits due to test equipment limitations.
Note 3: Guaranteed by design.
Note 4: Measured at Point A, circuit of Figure 2, with PDRV disconnected.
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 2, V+ = 5V, 100/200 = 12/15 = 0V; T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
EXT+, EXT-, I
L
= -1mA, V+ = 4.5V, PDRV= -3V
EXT+, EXT-, I
L
= 1mA, V+ = 4.5V, PDRV= -3V
V+ = 3.8V, SS = 2V
CC+, CC-
V+ = 4.5V, PDRV = -3V,
T
A
= +25°C
V+ = 4.5V, I
L
= -5mA, T
A
= +25°C
SS = 0V
CONDITIONS
mA-2 -0.5Soft-Start Sink Current
µA37Soft-Start Source Current
V-2.8V
OL
V4.3V
OH
Output Voltage High
Output Voltage Low
°C190Thermal-Shutdown Threshold
k10Compensation Pin Impedance
mA
100 200
Output Sink Current
200 350
V-3PUMP Output Voltage (Note 4)
UNITSMIN TYP MAXSYMBOLPARAMETER
EXT+ = 4.5V
EXT- = 4.5V
EXT+ = 0V
V+ = 4.5V, PDRV = -3V,
T
A
= +25°C
EXT- = -3V
mA
-200 -100
Output Source Current
-350 -200
EXT+, C
LOAD
= 2nF
ns
70
Output Rise/Fall Time
100EXT-, C
LOAD
= 4nF, PDRV = -3V

MAX742CWP+

Mfr. #:
Manufacturer:
Maxim Integrated
Description:
Switching Voltage Regulators Switch-Mode Regulator
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet