2

LT1239

ing circuitry. A low-battery detector with a 5V threshold

powers down the second regulator and the error amplifier

to limit the discharge voltage of the backup cells. This

prevents deep discharge damage to the lithium cells. Both

regulators have independent shutdown and current moni-

tor functions.

LT1239CS

ORDER PART

NUMBER

Consult factory for Industrial and Military grade parts.

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Regulator 1 (Notes 7, 8)

3.700

3.750

3.800

V

q

3.650

3.750

3.825

V

Line Regulation

q

210

mV

Load Regulation

– 12

– 25

mV

q

– 20

– 50

mV

– 20

mV

– 30

mV

Dropout Voltage (Note 9)

0.15

0.20

V

0.25

0.40

V

0.30

V

Ground Pin Current (Notes 10, 11)

q

20

30

µA

q

0.80

1.2

mA

1.35

mA

Adjust Pin Bias Current (Note 12)

40

120

nA

ELECTRICAL CHARACTERISTICS

(Note 1)

Input 1 Voltage ......................................................

±30V

Input 2 Voltage ............................................. 30V, – 0.6V

Output 1 Voltage ........................................... 30V, – 0.6V

Output 2 Voltage ............................................. 6V, – 0.6V

Adjust Pin Current ................................................ 10mA

SHDN1, SHDN2 (Note 2)

Input Voltage .............................................. 6V, – 0.6V

Input Current ...................................................... 5mA

5V Input Voltage ............................................. 6V, – 0.6V

Operating Temperature Range ......................... 0 to 70

°C

Junction Temperature Range ............................. (Note 6)

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

°C to 150°C

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

°C

TOP VIEW

S PACKAGE

16-LEAD PLASTIC SO

1

2

3

4

5

6

7

8

16

15

14

13

12

11

10

9

ADJ

GND

SHDN1

GND

GND

SHDN2

E/A (IN)

E/A (OUT)

OUT 1

INPUT 1

OUT 2

INPUT 2

NC