Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,

please contact the National Semiconductor Sales Office/

Distributors for availability and specifications.

V

IN

-0.3V to 6V

Storage Temperature Range

−65˚C to 150˚C

Junction Temperature

150˚C

Lead Temperature

(soldering, 10sec)

260˚C

ESD Rating

2.5kV

Operating Ratings

V

2.8V to 5.5V

Junction Temperature Range (T

−40˚C to

+125˚C

type apply over the full Junction Temperature Range (−40˚C to +125˚C). Minimum and Maximum limits are guaranteed

through test, design or statistical correlation. Typical values represent the most likely parametric norm at T

provided for reference purposes only. Unless otherwise specified V

Symbol

Parameter

Conditions

Min

Typ

Max

Unit

VFB

Feedback pin voltage

V

0.782

0.80

0.818

V

V

0.772

0.79

0.808

∆V

∆V

IN

Line Regulation

V

-5

mV/V

I

Q

Operating Quiescent current

V

400

600

µA

T

ON

Switch On-Time

LM1770S - (500ns)

0.4

0.5

0.6

µs

LM1770T - (1000ns)

0.8

1.0

1.2

LM1770U - (2000ns)

1.6

2.0

2.4

T

OFF_MIN

Minimum Off-Time

LM1770S - (500ns)

150

250

ns

LM1770T - (1000ns)

135

225

LM1770U - (2000ns)

120

220

T

D

Gate Drive Dead-Time

70

ns

I

FB

Feedback pin bias current

V

50

nA

V

UVLO

Under-voltage lock out

V

2.6

2.8

V

V

UVLO_HYS

Under-voltage lock out hysteresis

30

mV

V

SC_TH

Feedback pin Short Circuit Latch

Threshold

0.5

0.55

0.65

V

R

DS(ON) 1

HG FET driver pull-up On resistance

I

5

Ω

R

DS(ON) 2

HG FET driver pull-down On resistance I

9

Ω

R

DS(ON) 3

LG FET driver pull-up On resistance

I

9

Ω

R

DS(ON) 4

LG FET driver pull-down On resistance I

5

Ω

Note 1: Absolute Maximum Ratings indicate limits beyond which damage may occur to the device. Operating Ratings indicate conditions for which the device is

intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications, see Electrical Characteristics.

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