Linear Technology LT1910ES8 Datasheet

FEATURES

Final Electrical Specifications

LT1910

Protected High Side

MOSFET Driver

August 2002

U

DESCRIPTION

■

8V to 48V Power Supply Range

■

Protected from –15V to 60V Supply Transients

■

Short-Circuit Protected

■

Automatic Restart Timer

■

Open-Collector Fault Flag

■

Fully Enhances N-Channel MOSFET Switches

■

Programmable Current Limit, Delay Time and
Autorestart Period

■

Voltage Limited Gate Drive

■

Defaults to OFF State with Open Input

■

Available in SO-8 Package

U

APPLICATIO S

■

Industrial Control

■

Avionics Systems

■

Automotive Switches

■

Stepper Motor and DC Motor Control

■

Electronic Circuit Breaker

The LT®1910 is a high side gate driver allowing the use of
low cost N-channel power MOSFETs for high side switch­ing applications. It contains a completely self-contained
charge pump to fully enhance an N-channel MOSFET
switch with no external components.

When the internal drain comparator senses that the switch
current has exceeded the preset level, the switch is turned
off and a fault flag is asserted. The switch remains off for
a period of time set by an external timing capacitor and
then automatically attempts to restart. If the fault still
exists, this cycle repeats until the fault is removed, thus
protecting the MOSFET. The fault flag becomes inactive
once the switch restarts successfully.

The LT1910 has been specifically designed for harsh
operating environments such as industrial, avionics and
automotive applications where poor supply regulation
and/or transients may be present. The device will not
sustain damage from supply transients of –15V to 60V.

The LT1910 is available in the SO-8 package.

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

TYPICAL APPLICATIO

Fault Protected High Side Switch

5.1k

FAULT OUTPUT

OFF ON

U

Switch Drop vs Load Current

24V5V

LT1910

+

FAULT
IN
TIMER

0.1µF

V

SENSE

GATE

GND

+

10µF
50V

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen­tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

0.01Ω

IRFZ34

LOAD

1910 TA01

0.50

0.45

0.40

0.35

0.30

0.25

0.20

TOTAL DROP (V)

0.15

0.10

0.05
0

0

1

3

2

LOAD CURRENT (A)

4

5

1910 TA02

1910i

1

LT1910

WW

W

ABSOLUTE MAXIMUM RATINGS

U

U

W

PACKAGE/ORDER INFORMATION

U

(Note 1)

Supply Voltage (Pin 8)............................... –15V to 60V

Input Voltage (Pin 4) .................... (GND – 0.3V) to 15V

GATE Voltage (Pin 5) .............................................. 75V

SENSE Voltage (Pin 6)....................................... V+ ±5V

FAULT Voltage (Pin 3) ............................................ 36V

Current (Pins 1, 2, 4, 5, 6, 8) ............................... 40mA

Operating Temperature Range (Note 2) ...–40°C to 85°C

Junction Temperature Range................ –40°C to 125°C

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

GND
TIMER
FAULT

IN

T

JMAX

TOP VIEW

1

2

3

4

S8 PACKAGE

8-LEAD PLASTIC SO

= 125°C, θJA = 150°C/W

+

8

V
NC

7

SENSE

6

GATE

5

ORDER PART

NUMBER

LT1910ES8

S8 PART MARKING

1910

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

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

ELECTRICAL CHARACTERISTICS

range, otherwise specifications are at TA = 25°C. V+ = 12V to 48V unless otherwise noted.

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

I

S

∆I

S(ON)

V

INH

V

INL

I

IN

C

IN

V

T(TH)

V

T(CL)

I

T

V

SENSE

I

SENSE

V

– V+Gate Voltage Above Supply V+ = 8V 4 4.5 6 V

GATE

V

F(TH)

V

FOL

t

ON

t

OFF

t

OFF(CL)

Supply Current (OFF State) V+ = 48V, VIN = 0.8V 1.2 1.9 2.5 mA
Delta Supply Current (ON State) VIN = 2V, Measure Increase in I
Input High Voltage ● 2V
Input Low Voltage ● 0.8 V
Input Current VIN = 2V ● 15 30 50 µA

Input Capacitance (Note 3) 5pF
Timer Threshold Voltage VIN = 2V, Adjust V
Timer Clamp Voltage VIN = 0.8V 3.2 3.5 3.8 V
Timer Charge Current VIN = VT = 2V 9 14 20 µA
Drain Sense Threshold Voltage 50 65 80 mV

Temperature Coefficient (Note 3) 0.33 %/°C
Drain Sense Input Current V+ = 48V, V

FAULT Output High Threshold Voltage VIN = 2V, IF = 1mA, Adjust V
FAULT Output Low Threshold Voltage 3.0 3.3 3.6 V

FAULT Output Low Voltage IF = 1mA ● 0.07 0.4 V
Turn-On Time V+ = 24V, V
Turn-Off Time V+ = 24V, V
Current Limit Turn-Off Time V+ = 24V, (V+ – V

The ● denotes specifications that apply over the full operating temperature

S

= 5V ● 55 110 185 µA

V

IN

T

= 65mV 0.5 1.5 µA

SENSE

+

= 12V ● 7 8.5 10 V

V

+

= 24V ● 10 12 14 V

V
V+ = 48V ● 10 12 14 V

T

GATE
GATE

= 32V, C
= 2V, C

SENSE

= 1nF 100 220 400 µs

GATE

= 1nF 25 100 µs

GATE

)→0.1V, C

= 1nF 20 50 µs

GATE

● 2.6 2.9 3.2 V

3.1 3.4 3.7 V

0.8 1.2 mA

Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.

Note 2: The LT1910E 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: Guaranteed but not tested.

2

1910i

UW

TYPICAL PERFOR A CE CHARACTERISTICS

Supply Current vs Supply Voltage Supply Current vs Temperature Input Voltage vs Temperature

3.6

3.4

3.2

3.0

2.8

2.6

2.4

2.2

2.0

SUPPLY CURRENT (mA)

1.8

1.6

1.4

1.2
10

0

SUPPLY VOLTAGE (V)

20

ON STATE

OFF STATE

30

5.0
V+ = 48V

4.5

4.0

3.5

3.0

2.5

2.0

1.5

SUPPLY CURRENT (mA)

1.0

0.5

0

–25

40

50

1910 G01

–50

ON STATE

OFF STATE

25 50

0

TEMPERATURE (°C)

75

100

1910 G02

2.0

1.8

1.6

1.4

1.2

INPUT VOLTAGE (V)

1.0

0.8
–50

–25

V

V

02550

TEMPERATURE (°C)

LT1910

INH

INL

75 100

1910 G03

Input Current vs Temperature

200
180
160
140
120
100

80
60

INPUT CURRENT (µA)

40
20

0

–50

–25

VIN = 5V

VIN = 2V

25 50

0

TEMPERATURE (°C)

Timer Charge Current
vs Temperature

20

VIN = VT = 2V

18

16

14

12

TIMER CHARGE CURRENT (µA)

10

8

–50

02550

–25

TEMPERATURE (°C)

75

100

1910 G04

75 100

1910 G07

Timer Threshold Voltage
vs Temperature

3.2
VIN = 2V

3.1

3.0

2.9

2.8

2.7

TIMER THRESHOLD VOLTAGE (V)

2.6

–50

02550

–25

TEMPERATURE (°C)

Drain Sense Threshold Voltage
vs Temperature

90

V+ = 24V

85
80
75
70
65
60
55
50
45

DRAIN SENSE THRESHOLD VOLTAGE (mV)

40

–50

–25

25 50

0

TEMPERATURE (°C)

75 100

1910 G05

75

100

1910 G08

Timer Clamp Voltage
vs Temperature

3.8
VIN ≤ 0.8V

3.7

3.6

3.5

3.4

TIMER CLAMP VOLTAGE (V)

3.3

3.2

–50

02550

–25

TEMPERATURE (°C)

MOSFET Gate Voltage Above V
(V

– V+) vs Supply Voltage

GATE

16

) (V)

+

14

– V

GATE

12

(V

+

10

8

6

4

2

0

MOSFET GATE VOLTAGE ABOVE V

0

TA = 25°C

10 20 30 503551525 45

SUPPLY VOLTAGE (V)

75 100

1910 G06

+

TA = 85°C

TA = –40°C

40

LTC1266 • F04

1910i

3

LT1910

UW

TYPICAL PERFOR A CE CHARACTERISTICS

MOSFET Gate Drive Current
vs V

100

MOSFET GATE DRIVE CURRENT (µA)

GATE

10

1

0.1
024

+

– V

V+ = 8V V+ = 12V V+ ≥ 24V

6 8 10 12 14 16

V

– V+ (V)

GATE

1910 G10

Fault Threshold Voltage
vs Temperature

3.7
VIN = 2V

= 1mA

I

F

3.6

3.5

FAULT HIGH THRESHOLD

3.4

3.3

FAULT LOW THRESHOLD

3.2

FAULT THRESHOLD VOLTAGE (V)

3.1

–50

02550

–25

TEMPERATURE (°C)

Turn-On Time vs Temperature Turn-Off Time vs Temperature

400

V+ = 24V

= 32V

V

GATE

350

300

250

200

TURN-ON TIME (µs)

150

100

–50

C

GATE

= 1nF

02550

–25

TEMPERATURE (°C)

75 100

1910 G13

100

V+ = 24V

90
80
70
60
50
40
30

TURN-OFF TIME (µs)

20
10

0

–50

V
C

GATE
GATE

= 2V
= 1nF

CURRENT LIMIT

–25

0

TEMPERATURE (°C)

NORMAL

25 50

75 100

1910 G11

75

100

1910 G014

Fault Output Low Voltage
vs Temperature

0.20
IF = 1mA

0.18

0.16

0.14

0.12

0.10

0.08

0.06

0.04

FAULT OUTPUT LOW VOLTAGE (V)

0.02

0

–50

–25

25 50

0

TEMPERATURE (°C)

Automatic Restart Period
vs Temperature

1000

V+ = 24V

CT = 3.3µF

CT = 1µF

100

CT = 0.33µF

AUTOMATIC RESTART PERIOD (ms)

10

–50

–30

CT = 0.1µF

–10 10 30 50

TEMPERATURE (°C)

75

100

1910 G012

90

70

1910 G15

4

1910i