M
High-Voltage, Step-Down DC-DC
Controller in μMAX
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
IN, EXT,
SHDN
to GND...........................................-0.3V to +38V
VH to GND..............................................................-0.3V to +34V
VH, EXT to IN............................................................-7V to +0.3V
CS, OUT to GND ....................................................-0.3V to +20V
FB, 3/5, REF to GND.....................................-0.3V to (VL + 0.3V)
VL to GND...................................................................-0.3V to 6V
Continuous Power Dissipation (T
A
= +70°C)
10-Pin μMAX (derate 5.6mW/°C above 70°C) .............444mW
ELECTRICAL CHARACTERISTICS
(VIN=
SHDN
= 5.5V to 36V, 3/5 = GND, ILOAD = 0,
TA= 0°C to +85°C
, unless otherwise noted. Typical values at VIN=
SHDN
=
36V, TA= +25°C.)
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.
Operating Temperature Range
MAX174_EUB ..................................................-40°C to +85°C
MAX174_AUB................................................-40°C to +125°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s) ................................+300°C
PARAMETER
CONDITIONS
MIN
4.5
TYP
MAX
36
140
12
5.15
3.40
44
1.28
50
-4.3
5.5
4.1
115
150
25
0
UNITS
V
μA
μA
Input Voltage Range
Supply Current into IN
Shutdown Supply Current
SHDN
= V
IN
= 5.5V to 36V
SHDN
= GND
3/5 = VL
3/5 = GND
3/5 = VL, V
OUT
= 5V
Falling edge, hysteresis = 8mV
90
4
5.00
3.30
28
1.25
4.85
3.20
Output Voltage (MAX1744)
V
OUT Input Current (MAX1744)
FB Threshold Voltage (MAX1745)
FB Input Current (MAX1745)
VH Output Voltage with Respect to IN
VL Output Voltage
VL Undervoltage Lockout
μA
V
nA
V
V
V
1.22
-50
-6.0
4.5
2.0
85
80
0
-25
2.4
V
IN
= 5.5V to 36V, I
VH
= 100μA to 20mA
V
IN
= 5.5V to 36V, I
VL
= 100μA to 2mA
-5.3
5.0
3.0
100
110
15
V
CS
= V
OUT
= 2.5V to 18V
V
CS
= V
OUT
= GND
V
CS
= V
OUT
= 2.5V to 18V
V
CS
= V
OUT
= GND
V
IN
= 4.5V to 36V
V
IN
= 4.5V to 36V
SHDN
= GND
3/5 = GND
SHDN
= 36V
CS Threshold Voltage
mV
CS Input Current
μA
SHDN
, 3/5 Logic-High Threshold
SHDN
, 3/5 Logic-Low Threshold
3/5 Input Current
V
V
μA
0.4
±
1
±
1
12
20
2.5
1.5
SHDN
Input Current
μA
EXT Resistance
Minimum EXT Off-Time
Minimum EXT On-Time
Output Line Regulation
Output Load Regulation
Reference Voltage
REF Load Regulation
REF Line Regulation
8
μs
μs
1.5
0.7
2.0
1.0
5
15
1.25
4
30
Figure 1, 5.5V < V
IN
< 36V, I
LOAD
= 1A
Figure 1, V
IN
= 12V, 30mA < I
LOAD
< 2A
I
REF
= 0
0
≤
I
REF
≤
100μA
V
IN
= 4.5V to 36V, I
REF
= 0
mV/V
mV/A
V
mV
μV/V
1.22
1.28
10
60