Low-Cost Voltage-Mode PWM

Step-Down Controllers

2

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ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

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.

(All Voltages Referenced to GND, Unless Otherwise Noted)

VIN to GND (MAX1966)............................................-0.3V to +6V

VIN to GND (MAX1967)..........................................-0.3V to +30V

FB to GND ................................................................-0.3V to +6V

BST to LX..................................................................-0.3V to +6V

DH to LX........................................................-0.3V to BST + 0.3V

VL Short to GND (MAX1967) ....................................................5s

RMS Input Current (any pin).............................................±50mA

8-Pin SO (derate 5.88mW/°C above +70°C)................471mW

10-Pin µMAX (derate 5.6mW/°C above +70°C) ...........444mW

Operating Temperature Range ...........................-40°C to +85°C

Junction Temperature ......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

MAX1967 VIN Operating Range

4.9

28

V

MAX1967 Operating Range with

VIN = VL

2.7

5.5

V

MAX1966 VIN Operating Range

2.7

5.5

V

MAX1967 VL Undervoltage

Lockout (UVLO) Trip Level

Rising and falling edge, hysteresis = 2%

2.35

2.53

2.66

V

MAX1966 VIN UVLO

Trip Level

Rising and falling edge, hysteresis = 2%

2.35

2.53

2.66

V

Operating Supply Current

FB = 0.88V, no switching

0.7

3

mA

VL Output Voltage (MAX1967 Only)

FB = 0.88V

4.67

5

5.3

V

Thermal Shutdown (Note 1)

Rising temperature, typical hysteresis = 10°C

160

°C

OSCILLATOR

0°C to +85°C

82

102

124

Frequency

-40°C to +85°C

79

102

127

kHz

Minimum Duty Cycle

10

%

Maximum Duty Cycle

90

95

%

SOFT-START

Digital Ramp Period

Internal 6-bit DAC for converter to ramp from

0 to full output voltage

1024 /

s

Soft-Start Levels

64

V

ERROR AMPLIFIER

2.7V < VCC < 5.5V, 0°C to +85°C

0.787

0.800

0.815

FB Regulation Voltage

(MAX1967)

2.7V < VCC < 5.5V, -40°C to +85°C

0.782

0.800

0.815

V

2.7V < VIN < 5.5V, 0°C to +85°C

0.787

0.800

0.815

FB Regulation Voltage

(MAX1966)

2.7V < VIN < 5.5V, -40°C to +85°C

0.782

0.800

0.815

V

FB to COMP/EN Gain

4000

V/V