Name: LT1076HVIT
SKU: LT1076HVIT
Price: 15.71291 USD
Availability: InStock

LT1074/LT1076

, LTC and LT are registered trademarks of Linear Technology Corporation.

APPLICATIO S

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

Step-Down Switching

Regulator

The LT

1074 is a 5A (LT1076 is rated at 2A) monolithic

bipolar switching regulator which requires only a few

external parts for normal operation. The power switch, all

oscillator and control circuitry, and all current limit com-

ponents, are included on the chip. The topology is a classic

■

Buck Converter with Output Voltage Range of 2.5V

to 50V

■

Tapped-Inductor Buck Converter with 10A Output

at 5V

■

Positive-to-Negative Converter

■

Negative Boost Converter

■

Multiple Output Buck Converter

■

5A Onboard Switch (LT1074)

■

100kHz Switching Frequency

■

Greatly Improved Dynamic Behavior

■

Available in Low Cost 5 and 7-Lead Packages

■

Only 8.5mA Quiescent Current

■

Programmable Current Limit

■

Operates Up to 60V Input

■

Micropower Shutdown Mode

positive “buck” configuration but several design innova-

tions allow this device to be used as a positive-to-negative

converter, a negative boost converter, and as a flyback

converter. The switch output is specified to swing 40V

below ground, allowing the LT1074 to drive a tapped-

inductor in the buck mode with output currents up to 10A.

The LT1074 uses a true analog multiplier in the feedback

loop. This makes the device respond nearly instanta-

neously to input voltage fluctuations and makes loop gain

independent of input voltage. As a result, dynamic behav-

ior of the regulator is significantly improved over previous

designs.

On-chip pulse by pulse current limiting makes the LT1074

nearly bust-proof for output overloads or shorts. The input

voltage range as a buck converter is 8V to 60V, but a self-

boot feature allows input voltages as low as 5V in the

inverting and boost configurations.

The LT1074 is available in low cost TO-220 or TO-3

packages with frequency pre-set at 100kHz and current

limit at 6.5A (LT1076 = 2.6A). A 7-pin TO-220 package is

also available which allows current limit to be adjusted

down to zero. In addition, full micropower shutdown can

be programmed. See Application Note 44 for design

details.

A fixed 5V output, 2A version is also available. See LT1076-5.

Buck Converter Efficiency

Basic Positive Buck Converter

GND

LT1074

500

µF

2.8k

2.21k

MBR745*

10V TO 40V

†

200µF

2.7k

0.01

µF

L1**

µH (LT1074)

100

µH (LT1076)

USE MBR340 FOR LT1076

COILTRONICS #50-2-52 (LT1074)

#100-1-52 (LT1076)

PULSE ENGINEERING, INC.

#PE-92114 (LT1074)

#PE-92102 (LT1076)

HURRICANE #HL-AK147QQ (LT1074)

#HL-AG210LL (LT1076)

RIPPLE CURRENT RATING ≥ I

OUT

†

LT1074•TA01

25V

OUTPUT LOAD CURRENT (A)

EFFICIENCY (%)

1234

LT1074•TPC27

100

L = 50µH TYPE 52 CORE

DIODE = MBR735

V = 5V, V = 15V

OUT IN

V = 12V, V = 20V

OUT IN

LT1074

LT1074/LT1076

ABSOLUTE AXI U RATI GS

PACKAGE/ORDER I FOR ATIO

UUW

(Note 1)

*Assumes package is soldered to 0.5 IN

of 1 oz. copper over internal ground plane or over back side plane.

LT1076CQ

LT1076IQ

LT1076CR

LT1076IR

LT1076HVCR

LT1076HVIR

LT1074CT7

LT1074HVCT7

LT1074IT7

LT1074HVIT7

LT1076CT7

LT1076HVCT7

LT1074CT

LT1074HVCT

LT1074IT

LT1074HVIT

LT1076CT

LT1076HVCT

LT1076IT

LT1076HVIT

LT1074CK

LT1074HVCK

LT1074MK

LT1074HVMK

LT1076CK

LT1076HVCK

LT1076MK

LT1076HVMK

Input Voltage

LT1074/ LT1076 .................................................. 45V

LT1074HV/LT1076HV ......................................... 64V

Switch Voltage with Respect to Input Voltage

LT1074/ LT1076 .................................................. 64V

LT1074HV/LT1076HV ......................................... 75V

Switch Voltage with Respect to Ground Pin (V

Negative)

LT1074/LT1076 (Note 7) ..................................... 35V

LT1074HV/LT1076HV (Note 7) ........................... 45V

Feedback Pin Voltage..................................... –2V, +10V

Shutdown Pin Voltage (Not to Exceed V

).............. 40V

LIM

Pin Voltage (Forced) ............................................ 5.5V

Maximum Operating Ambient Temperature Range

Commercial .................................................0°C to 70°C

Industrial ................................................ –40°C to 85°C

Military ................................................. –55°C to 125°C

Maximum Operating Junction Temperature Range

Commercial ...............................................0°C to 125°C

Industrial .............................................. –40°C to 125°C

Military ................................................. –55°C to 150°C

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

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

ORDER PART

NUMBER

ORDER PART

NUMBER

LT1076: θ

= 4°C, θ

= 30°C/W

LT1076: θ

= 4°C, θ

= 30°C/W

LT1074: θ

= 2.5°C, θ

= 50°C/W

LT1076: θ

= 4°C, θ

= 50°C/W

LT1074: θ

= 2.5°C, θ

= 35°C/W

LT1076: θ

= 4°C, θ

= 35°C/W

LT1074: θ

= 2.5°C, θ

= 50°C/W

LT1076: θ

= 4°C, θ

= 50°C/W

Q PACKAGE

5-LEAD PLASTIC DD

FRONT VIEW

GND

FB/SENSE

R PACKAGE

7-LEAD PLASTIC DD

FRONT VIEW

SHDN

FB/SENSE

GND

LIM

CASE

IS GND

K PACKAGE

4-LEAD TO-3 METAL CAN

BOTTOM VIEW

T PACKAGE

5-LEAD PLASTIC TO-220

LEADS ARE FORMED STANDARD FOR

STRAIGHT LEADS, ORDER FLOW 06

GND

FRONT VIEW

T7 PACKAGE

7-LEAD PLASTIC TO-220

SHDN

GND

LIM

FRONT VIEW

TAB IS

GND

TAB IS

GND

TAB IS

GND

TAB IS

GND

LT1074/LT1076

The ● denotes the specifications which apply over the full operating

temperature range, otherwise specifications are at T

= 25°C. T

= 25°C, V

= 25V, unless otherwise noted.

PARAMETER CONDITIONS MIN TYP MAX UNITS

Switch “On” Voltage (Note 2) LT1074 I

= 1A, T

≥ 0°C 1.85 V

= 1A, T

< 0°C 2.1 V

= 5A, T

≥ 0°C 2.3 V

= 5A, T

< 0°C 2.5 V

LT1076 I

= 0.5A ● 1.2 V

= 2A ● 1.7 V

Switch “Off” Leakage LT1074 V

≤ 25V, V

= 0 5 300 µA

= V

MAX,

= 0 (Note 8) 10 500 µA

LT1076 V

= 25V, V

= 0 150 µA

= V

MAX,

= 0 (Note 8) 250 µA

Supply Current (Note 3) V

= 2.5V, V

≤ 40V ● 8.5 11 mA

40V < V

< 60V ● 912 mA

SHUT

= 0.1V (Device Shutdown) (Note 9) ● 140 300 µA

Minimum Supply Voltage Normal Mode ● 7.3 8 V

Startup Mode (Note 4)

● 3.5 4.8 V

Switch Current Limit (Note 5) LT1074 I

LIM

Open ● 5.5 6.5 8.5 A

LIM

= 10k (Note 6) 4.5 A

LIM

= 7k (Note 6) 3 A

LT1076 I

LIM

Open ● 2 2.6 3.2 A

LIM

= 10k (Note 6) 1.8 A

LIM

= 7k (Note 6) 1.2 A

Maximum Duty Cycle ● 85 90 %

Switching Frequency 90 100 110 kHz

≤ 125°C ● 85 120 kHz

> 125°C ● 85 125 kHz

= 0V through 2kΩ (Note 5) 20 kHz

Switching Frequency Line Regulation 8V ≤ V

≤ V

MAX

(Note 8) ● 0.03 0.1 %/V

Error Amplifier Voltage Gain (Note 7) 1V ≤ V

≤ 4V 2000 V/V

Error Amplifier Transconductance 3700 5000 8000 µmho

Error Amplifier Source and Sink Current Source (V

= 2V) 100 140 225 µA

Sink (V

= 2.5V) 0.7 1 1.6 mA

Feedback Pin Bias Current V

= V

REF

● 0.5 2 µA

Reference Voltage V

= 2V ● 2.155 2.21 2.265 V

Reference Voltage Tolerance V

REF

(Nominal) = 2.21V ±0.5 ±1.5 %

All Conditions of Input Voltage, Output

● ±1 ±2.5 %

Voltage, Temperature and Load Current

Reference Voltage Line Regulation 8V ≤ V

≤ V

MAX

(Note 8) ● 0.005 0.02 %/V

Voltage at 0% Duty Cycle 1.5 V

Over Temperature

● –4 mV/°C

Multiplier Reference Voltage 24 V

Shutdown Pin Current V

= 5V ● 51020 µA

≤ V

THRESHOLD

(≅2.5V) ● 50 µA

Shutdown Thresholds Switch Duty Cycle = 0 ● 2.2 2.45 2.7 V

Fully Shut Down

● 0.1 0.3 0.5 V

Thermal Resistance Junction to Case LT1074 2.5 °C/W

LT1076 4.0 °C/W

ELECTRICAL CHARACTERISTICS

Part #	LT1076HVIT
Description	IC REG MULT CONFIG INV ADJ TO220
Category	RECTIFIER
Availability	In Stock
Qty	2

LT1076HVIT

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