LT1073

2

Rev B

PIN CONFIGURATION

ABSOLUTE MAXIMUM RATINGS

Supply Voltage, Step-Up Mode .................................15V

Supply Voltage, Step-Down Mode ............................36V

SW1 Pin Voltage .......................................................50V

SW2 Pin Voltage ............................................–0.4 to VIN

Feedback Pin Voltage (LT1073)...................................5V

Switch Current.........................................................1.5A

Maximum Power Dissipation ............................. 500mW

Operating Temperature Range ..................... 0°C to 70°C

Storage Temperature Range .................. –65°C to 150°C

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

(Note 1)

ELECTRICAL CHARACTERISTICS

SYMBOL

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

IQ

Quiescent Current

Switch Off

l

95

130

µA

IQ

Quiescent Current, Step-Up

Mode Configuration

No Load

LT1073-5

LT1073-12

135

250

µA

µA

VIN

Input Voltage

Step-Up Mode

l

1.15

1.0

12.6

12.6

V

V

Step-Down Mode

l

30

V

Comparator Trip Point Voltage

LT1073 (Note 2)

l

202

212

222

mV

VOUT

Output Sense Voltage

LT1073-5 (Note 3)

LT1073-12 (Note 3)

l

l

4.75

11.4

5

12

5.25

12.6

V

V

Comparator Hysteresis

LT1073

l

5

10

mV

Output Hysteresis

LT1073-5

LT1073-12

l

l

125

300

250

600

mV

mV

fOSC

Oscillator Frequency

l

15

19

23

kHz

DC

Duty Cycle

Full Load (VFB = VREF)

l

65

72

80

%

tON

Switch ON Time

l

30

38

50

µs

IFB

Feedback Pin Bias Current

LT1073, VFB = 0V

l

10

50

nA

ISET

Set Pin Bias Current

VSET = VREF

l

60

120

nA

VAO

AO Output Low

IAO = –100µA

l

0.15

0.4

V

Reference Line Regulation

1V ≤ VIN ≤ 1.5V

1.5V ≤ VIN ≤ 12V

l

l

0.35

0.05

1.0

0.1

%V

%V

VCESAT

Switch Saturation Voltage

Set-Up Mode

VIN = 1.5V, ISW = 400mA

l

300

400

600

mV

mV

VIN = 1.5V, ISW = 500mA

l

400

550

750

mV

mV

VIN = 5V, ISW = 1A

l

700

1000

1500

mV

mV

AV

A2 Error Amp Gain

RL = 100kΩ (Note 4)

l

400

1000

V/V

The l denotes the specifications which apply over the full operating

temperature range, otherwise specifications are at TA = 25°C. VIN = 1.5V unless otherwise specified.

1

2

3

4

8

7

6

5

TOP VIEW

ILIM

VIN

SW1

SW2

FB (SENSE)*

SET

A0

GND

N8 PACKAGE

8-LEAD PDIP

S8 PACKAGE

8-LEAD PLASTIC SO

*FIXED VERSIONS

TJMAX = 125°C, θJA = 100°C/W (N8)

TJMAX = 125°C, θJA = 120°C/W (S8)

ORDER PART

NUMBER

LT1073CN8

LT1073CN8-5

LT1073CN8-12

LT1073CS8

LT1073CS8-5

LT1073CS8-12

S8 PART MARKING

1073

10735

107312

Consult factory for parts specified with wider operating temperature ranges.