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Electrical characteristics – Rainbow Electronics MAX1745 User Manual

Page 4

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MAX1744/MAX1745

High-Voltage, Step-Down DC-DC
Controller in µMAX

4

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ELECTRICAL CHARACTERISTICS

(VIN = SHDN = 5.5V to 36V, 3/5 = GND, ILOAD = 0, TA = -40°C to +125°C, unless otherwise noted.) (Note 1)

PARAMETER

CONDITIONS

MIN

MAX

UNITS

Input Voltage Range

4.5

36

V

Supply Current into IN

SHDN = V

IN

= 5.5V to 36V

140

µA

Shutdown Supply Current

SHDN = GND

15

µA

3/5 = VL

4.85

5.15

Output Voltage (MAX1744)

3/5 = GND

3.20

3.40

V

OUT Input Current (MAX1744)

3/5 = VL, V

OUT

= 5V

44

µA

FB Threshold Voltage (MAX1745)

Falling edge, hysteresis = 8mV

1.22

1.28

V

FB Input Current (MAX1745)

-50

50

nA

VH Output Voltage with Respect to IN

V

IN

= 5.5V to 36V, I

VH

= 100µA to 20mA

-6.0V

-4.3V

V

VL Output Voltage

V

IN

= 5.5V to 36V, I

VL

= 100µA to 2mA

4.5

5.5

V

VL Undervoltage Lockout

1.6

4.1

V

V

CS

= V

OUT

= 2.5V to 18V

85

115

CS Threshold Voltage

V

CS

= V

OUT

= GND

80

150

mV

V

CS

= V

OUT

= 2.5V to 18V

0

25

CS Input Current

V

CS

= V

OUT

= GND

-25

0

µA

SHDN, 3/5 Logic-High Threshold

V

IN

= 4.5V to 36V

2.4

V

SHDN, 3/5 Logic-Low Threshold

V

IN

= 4.5V to 36V

0.4

V

3/5 Input Current

SHDN = GND

±1

µA

3/5 = GND

±1

SHDN Input Current

SHDN = 36V

12

µA

EXT Resistance

20

Minimum EXT Off-Time

1.5

2.5

µs

Minimum EXT On-Time

0.7

1.5

µs

Reference Voltage

I

REF

= 0

1.22

1.28

V

REF Load Regulation

0

≤ I

REF

≤ 100µA

10

mV

REF Line Regulation

V

IN

= 4.5V to 36V, I

REF

= 0

80

µV/V

Note 1: Specifications to -40°C are guaranteed by design, not production tested.