Rev1.0

Preliminary and all contents are subject to change without prior notice.

9/4/2012

SE1484

3A 27V Synchronous Buck Converter

Recommended Operating Conditions

Parameter

Symbol

Value

Units

Supply Input Voltage

4.5 to +27

V

Operating Junction Temperature

-20 to +125

°C

Electrical Characteristics

Parameter

Symbol

Conditions

Min

Typ

Max

Unit

Feedback Voltage

4.5V

≤ V

0.9

0.925

0.95

V

Feedback Overvoltage Threshold

1.1

V

High-Side Switch-On Resistance*

90

mΩ

Low-Side Switch-On Resistance*

70

mΩ

High-Side Switch Leakage

,

0.1

10

uA

Upper Switch Current Limit*

Min Duty Cycle

3.8

4.5

A

Lower Switch Current Limit*

From Drain to

Source

1.2

A

COMP to Current Limit Trans conductance

5.2

A/V

Error Amplifier Trans conductance

ΔI

900

uA/V

Error Amplifier DC Gain*A

400

V/V

Switching Frequency

300

340

380

KHz

Short Circuit Switching Frequency

100

KHz

Minimum Duty Cycle

7.5

%

Maximum Duty Cycle

92

%

EN Shutdown Threshold Voltage

1.1

1.4

2

V

EN Shutdown Threshold Voltage Hysteresis

180

mV

EN Lockout Threshold Voltage

2.2

2.5

2.7

V

EN Lockout Hysteresis

150

mV

Supply Current in Shutdown

0.3

3.0

uA

IC Supply Current in Operation

1.3

1.5

mA

Input UVLO Threshold Rising

UVLO

3.8

4.0

4.4

V

Input UVLO Threshold Hysteresis

150

mV

Soft-start Current

6

uA

Soft-start Period

15

mS

Thermal Shutdown Temperature*

Hysteresis =25°C

155

℃

Note: * Guaranteed by design, not tested