Micrel, Inc.

MIC2251

April 2011

3

M9999-041811-B

Absolute Maximum Ratings

(1)

Ambient Storage Temperature (Ts) ..........–65°C to +150°C

ESD Rating

Operating Ratings

(2)

Junction Thermal Resistance

Electrical Characteristics

(5)

Symbol

Parameter

Condition

Min

Typ

Max

Units

Input Voltage Range

2.5

5.5

V

Under-voltage Lockout

1.8

2

2.4

V

Quiescent Current

70

120

µA

Shutdown Current

0.1

1

µA

1.20

1.24

1.277

V

Feedback Voltage

1.19

1.29

V

Feedback Input Current

10

nA

PFM Operation

Tss

Soft Start time

1

ms

Switch Off-time

1.6

µs

Maximum Duty Cycle

75

87

%

Off-time Dithering

±20

%

Line Regulation

0.3

2

%

Load Regulation

0.1

2

%

Switch Current Limit

Note 7

0.9

1.6

A

Switch ON-resistance

0.7

1

Ω

Switch Leakage Current

0.01

5

µA

Turn ON

1.5

V

Logic Input Thresholds

Turn OFF

0.4

V

Enable Pin Current

0.1

2

µA

130

°C

T

Thermal Shutdown Threshold

Hysteresis

15

°C

Notes:

1. Absolute maximum ratings indicate limits beyond which damage to the component may occur.

2. The device is not guaranteed to function outside its operating rating.

thermal shutdown.

4. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5kΩ in series with 100pF.

5. Specification for packaged product only.

7. Guaranteed by design.