2

LT1944

ABSOLUTE

AXI U

RATI GS

PACKAGE/ORDER I FOR ATIO

(Note 1)

SW1, SW2 Voltage .................................................. 36V

Current into FB1, FB2 Pins ..................................... 1mA

Junction Temperature ........................................... 125

°C

Operating Temperature Range (Note 2) .. – 40

°C to 85°C

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

°C to 150°C

Lead Temperature (Soldering, 10 sec).................. 300

°C

ORDER PART

NUMBER

LT1944EMS

MS10 PART

MARKING

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Minimum Input Voltage

1.2

V

Quiescent Current, Each Switcher

Not Switching

20

30

µA

1

µA

FB Comparator Trip Point

q

1.205

1.23

1.255

V

FB Comparator Hysteresis

8mV

FB Voltage Line Regulation

0.05

0.1

%/V

FB Pin Bias Current (Note 3)

q

30

80

nA

Switch Off Time

400

ns

1.5

µs

250

350

mV

Switch Current Limit

250

350

400

mA

SHDN Pin Current

2

3

µA

8

12

µA

SHDN Input Voltage High

0.9

V

SHDN Input Voltage Low

0.25

V

Switch Leakage Current

0.01

5

µA

Note 1: Absolute Maximum Ratings are those values beyond which the life

of a device may be impaired.

Note 2: The LT1944 is guaranteed to meet performance specifications

from 0

°C to 70°C. Specifications over the –40°C to 85°C operating

temperature range are assured by design, characterization and correlation

with statistical process controls.

Note 3: Bias current flows into the FB pin.

LTTR

1

2

3

4

5

FB1

SHDN1

GND

SHDN2

FB2

10

9

8

7

6

SW1

PGND

PGND

SW2

TOP VIEW

MS10 PACKAGE

10-LEAD PLASTIC MSOP

Consult LTC Marketing for parts specified with wider operating temperature ranges.