MIC4574

Micrel

4-94

April 1998•

Electrical Characteristics

V

Parameter

Condition

Min

Typ

Max

Units

MIC4574 [Adjustable]

Feedback Voltage

1.217

1.230

1.243

V

Feedback Voltage

8V

≤ V

1.193

1.230

1.267

V

1.180

1.280

V

Efficiency

I

77

%

Feedback Bias Current

50

100

nA

500

nA

MIC4574-3.3

Output Voltage

3.234

3.3

3.366

V

Output Voltage

6V

≤ V

3.168

3.3

3.432

V

3.135

3.465

V

Efficiency

72

%

MIC4574-5.0

Output Voltage

4.900

5.0

5.100

V

Output Voltage

8V

≤ V

4.800

5.0

5.200

V

4.750

5.250

V

Efficiency

77

%

MIC4574 / -3.3 / -5.0

Oscillator Frequency

180

200

220

kHz

Saturation Voltage

I

1

1.3

V

1.5

V

Maximum Duty Cycle (On)

FB connected to 0V

90

95

%

Current Limit

Peak Current, t

0.7

1.0

1.6

A

0.65

1.8

A

Output Leakage Current

V

Output = 0V

0

2

mA

Output = –1V

7.5

30

mA

Quiescent Current

510

mA

Standby Quiescent Current

SHDN = 5V (regulator off)

50

200

µA

SHDN Input Logic Level

V

2.2

1.4

V

2.4

V

V

1.2

1.0

V

0.8

V

SHDN Input Current

SHDN = 5V (regulator off)

4

30

µA

SHDN = 0V (regulator on)

–10

0.01

10

µA

General Note: Devices are ESD protected, however, handling precautions are recommended.

Note 1:

The MIC4574 is not guaranteed to survive a short circuit to ground for input voltage above 24V.

Absolute Maximum Ratings

Supply Voltage (V

Shutdown (V

Output Switch (V

Junction Temperature (T

Storage Temperature ............................... –65

°C to +150°C

Operating Ratings

Supply Voltage (V

Package Thermal Resistance

θ

θ