Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,

please contact the National Semiconductor Sales Office/

Distributors for availability and specifications.

Voltages from the indicated pins to GND:

VIN

-0.3V to 40V

SW (Note 7)

-0.5V to 40V

VDD

-0.3V to 7V

VBIAS

-0.3V to 10V

FB

-0.3V to 6V

BOOT

SW-0.3V to SW+7V

PGOOD

-0.3V to 7V

FREQ

-0.3V to 7V

SYNC

-0.3V to 7V

EN

-0.3V to 40V

FPWM

-0.3V to 7V

SS

-0.3V to 7V

Storage Temperature

-65˚C to +150˚C

Power Dissipation (Note 2)

2.6 W

Recommended Lead

Temperature

Vapor Phase (70s)

215˚C

Infrared (15s)

220˚C

ESD Susceptibility (Note 3)

Machine Model

200V

Human Body Model

2KV

Charged Device Model

1kV

Operating Ratings (Note 1)

Operating Junction Temp.

−40˚C to 125˚C

Supply Voltage (Note 4)

3.0V to 38V

apply over the junction temperature (T

mum limits are guaranteed through test, design, or statistical correlation. Typical values represent the most likely parametric

norm at T

Symbol

Parameter

Conditions

Min

Typ

Max

Unit

System

I

SD (Note 6)

Shutdown Current

EN = 0V

9.5

20

µA

Iq

_Sleep_VB (Note

6)

Quiescent Current

Sleep mode, VBIAS = 5V

38

70

µA

Iq

_Sleep_VDD

Quiescent Current

Sleep mode, VBIAS = GND

83

150

µA

Iq

_PWM_VB

Quiescent Current

PWM mode, VBIAS = 5V

150

230

µA

Iq

_PWM_VDD

Quiescent Current

PWM mode, VBIAS = GND

0.65

0.85

mA

I

BIAS_Sleep (Note 6)

Bias Current

Sleep mode, VBIAS = 5V

43

105

µA

I

BIAS_PWM

Bias Current

PWM mode, VBIAS = 5V

0.5

0.70

mA

V

FB

Feedback Voltage

1.2155

1.234

1.2525

V

I

FB

FB Bias Current

nA

∆V

∆V

IN

Vout line regulation

0.001

%/V

∆V

∆I

OUT

Vout load regulation

0.07

%

VDD

VDD output voltage

5mA

5.50

5.95

6.50

V

I

SS_Source

Soft-start source current

0.9

2.3

3.6

µA

V

bias_th

VBIAS switchover threshold

2.50

2.7

3.05

V

Switching

R

DS(ON)

Switch on Resistance

Isw = 1A

0.12

0.2

0.42

Ω

I

sw_off

Switch off state leakage current

Vin = 38V, VSW = 0V

0.002

5.0

µA

f

sw

Switching Frequency

RFREQ = 62k, 124k, 240k

%

V

FREQ

FREQ voltage

1.0

V

f

Switching Frequency range

150

500

kHz

V

SYNC

Sync pin threshold

SYNC rising

1.2

1.6

V

SYNC falling

0.8

1.1

Sync pin hysteresis

114

mV

I

SYNC

SYNC leakage current

6

nA

F

SYNC_UP

Upper frequency synchronization

range

As compared to nominal f

SW

+30

%

F

SYNC_DN

Lower frequency synchronization

range

As compared to nominal f

SW

-20

%

www.national.com

3