User Manual

MAX746
High-Efficiency, PWM, Step-Down,
N-Channel DC-DC Controller
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
Supply Voltage V+, AV+ to GND..............................-0.3V to 17V
HIGH, EXT to GND....................................................-0.3V to 21V
AGND to GND..........................................................-0.3V to 0.3V
All Other Pins................................................-0.3V to (V+ + 0.3V)
Reference Current (I
REF
)....................................................±2mA
Continuous Power Dissipation (T
A
= +70°C)
Plastic DIP (derate 10.53mW/°C above +70°C) ..........842mW
Narrow SO (derate 8.70mW/°C above +70°C) ............696mW
CERDIP (derate 10.00mW/°C above +70°C)...............800mW
Operating Temperature Ranges:
MAX746C_E........................................................0°C to +70°C
MAX746E_E.....................................................-40°C to +85°C
MAX746MJE ..................................................-55°C to +125°C
Junction Temperatures:
MAX746C_E/E_E..........................................................+150°C
MAX746MJE.................................................................+175°C
Storage Temperature Range.............................-65°C to +160°C
Lead Temperature (soldering, 10sec).............................+300°C
ELECTRICAL CHARACTERISTICS
(V+ = 10V, I
LOAD
= 0A, I
REF
= 0µA, T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
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.
PARAMETER SYMBOL MIN TYP MAX UNITS
Efficiency 94 %
Load Regulation 1.3 2.5 %
Line Regulation
0.1
%/V
OUT Leakage Current 50 80
µA
FB Input Logic Low 40 mV
Output Voltage
Input Voltage 415V
V
OUT
4.85 5.08 5.25 V
Feedback Voltage V
FB
V
Reference Voltage V
REF
1.96 2.00 2.04
Reference Load Regulation 920mV
Soft-Start Source Current 0.5 1.0 1.5
µA
Soft-Start Fault Current (Note 1) 100 500
µA
Supply Current (Note 2) I
SUPP
1.7
mA
0.95
1.4 20
µA
Oscillator Frequency f
OSC
80 100 120
kHz
CONDITIONS
I
REF
= 0µA to 100µA
0V < (V+ - CS) < 0.125V
V+ = 4V to 15V, external feedback mode
V
OUT
= 5V
For dual-mode switchover
SS = 0V
SS = 2V
Operating, V+ = 15V
Operating, V+ = 10V
Shutdown mode
(V+ - CS) = 0V,
external feedback mode
FB Input Leakage Current 1 100 nAFB = 2V
I
REF
= 0µA
MAX746E/M
MAX746E/M 1.95 2.00 2.05
MAX746C
V+
V+ = 6V to 15V, 0V < (V+ - CS) < 0.125V,
FB = 0V (includes line and load regulation)
MAX746C 1.96 2.00 2.04
V+ = 6V to 15V, FB = 0V 0.05
Circuit of Figure 1, I
LOAD
= 0.5A to 2.5A,
V+ = 6V
1.97 2.00 2.03
V
MAX746E/M
MAX746C 1.1 1.4
MAX746E/M
85 100 115MAX746C