Datasheet NJM3545T Specification

UNIVERSAL SINK DRIVER

■ GENERAL DESCRIPTION ■ PACKAGE OUTLINE

NJM3545 is a bipolar universal high-current highly protected

low side driver with transparent input and 2000mA continuous

-current sink capability. A high-level input activates the output.
The driver is equipped with extensive electrical protection;

such as over current protection and thermal protection,

which makes the device virtually indestructible.

Furthermore it can detect open circuit and short circuit to ground.

A special feature is the Error indicating output function pin

which signals to the host system if the protection or the load
check functions is activated.

The NJM3545 and NJM3548 are complementary drivers and

have similar data.

■ FEATURES

• 2000mA continuous-output current

NJM3545TA2

NJM3545

• Short circuit to VCC protection

• Error signal to host system

• Open circuit detection

• Short circuit to ground detection

• Thermal protection

• Built-in protection diodes

• Package TO-220 (5-pin)

■ BLOCK DIAGRAM

NJM3545

Input

Error

To logic

Voltage reference

QRS

Open circuit
detection

Supply

Thermal
protection

Short-circuit to
V protection

cc

Short-circuit to
GND detection

Output

Figure 1. Block Diagram

GND

■ PIN CONFIGURATION

NJM3545

NJM3545TA2

5
4
3
2
1

Input
Error
GND
Output
Supply

Figure 2. Pin description

■ PIN DESCRIPTION

TO-220 Symbol Description

1 Supply Supply voltage. Nominally 5 V to 40 V.
2 Output Output pin. Current flows from supply through the load into the pin. Nominal current is 8 mA to 2 A.
3 GND Ground supply.

diode are bonded to a separate pin.

4 Error Error indicating pin. Sinks current to ground if the protection and/or detection circuitry is activated.

Note: the current must be externally limited to 8 mA.

5 Input TTL compatible input. A LOW input signal turns the output transistor off and a HIGH input turns it on.

Output
voltage

V

cc

3.5 V

2.1 V

Open circuit

0.6 V

0.2 V

(min 0.5 mA, max 8 mA)

Undefined area

I

OMIN

Short circuit to GND error

NJM3545

Active output

Overload or short
circuit to V Error

cc

Undefined area

Normal operation

Undefined area

Undefined area

Short circuit protection

I

OS

(min 2 A, max 4.5 A)

Output
current

Figure 3. Error state vs. output voltage and output current, active
output (2.0 ≤ VIN ≤ VCC), 5 V < VCC < 40 V, - 40°C <TJ < +100°C

Output
voltage

NJM3545

Inactive output

100% V

cc

Normal operation

70% V

cc

Undefined area

50% V

cc

Short circuit to GND Error

0% V

cc

Figure 4. Error state vs. output voltage,
inactive output (0 V ≤ VIN ≤ 0.8 V), 5 V ≤
VCC ≤ 40 V, - 40°C < TJ < +100°C

NJM3545

■ FUNCTIONAL DESCRIPTION

The circuit NJM3545 is a low side driver capable of driving resistive or inductive loads not exceeding 2 A.

The driver has an error indicating function which generates an Error output signal when a fault condition has

occurred.

The circuits NJM3545 and NJM3548 are complementary drivers with equivalent functions and similar data.

NJM3545 is a sink driver and NJM3548 is a source driver.

Input stage

The output stage is switched on and off according to the status of the input. HIGH level activates the output. If the
input is left open, the circuit will accept it as a LOW level.

Output stage

The output stage contains a power transistor and two clamping diodes. The diodes are used for terminating line
transients from inductive loads. If the driver is inactive and the output is shorted to GND the driver will leak maxi­mum
8 µA. See figure 18.

Protection circuit

The circuit contains two protection circuits:

• Overload and Short circuit protection

• Thermal protection

The overload and short circuit protection will be activated at I

The output will be turned off immediately and latched to a high-impedance state after an overload or short circuit

has been detected.

= 3.5 A typically at TJ= +25°C, see figure 20.

out

1

Input

I

Ref

5

CC

2

Output

3

GND

3

Figure 6. Output stageFigure 5. Input stage

Fault condition Input Output Error How to resume normal operation

LOW=Error
HIGH=Normal

Normal 0 LOW 1 OFF 1 HIGH ——

1 HIGH 0 ON 1 HIGH ——

V

Short to GND 0 LOW 1 OFF 0 LOW Remove fault condition.

OUT

1 HIGH 0 ON 0 LOW Remove fault condition.

V

Short to V

OUT

Open load 0 LOW 1 OFF 1 HIGH ——

Over temperature 0 LOW 1 OFF 1 HIGH ——

=130 °C 1 HIGH 1 OFF 0 LOW Temperature is reduced to approx 120°C, or turn off the driver.

T

J

Figure 7. Error table

0 LOW 1 OFF 1 HIGH ——

CC

1 HIGH 1 OFF 0 LOW Turn off and on after fault condition is removed.

1 HIGH 0 ON 0 LOW Attach proper load to output or turn off the driver.

GND

NJM3545

A logic-level change at the input will reset the internal error latch. If the fault still is present at turn-on, the circuit

will once again turn the output off.

Due to a slight delay in the circuit, a high current transient will occur when the output is shorted to Vcc. This
current transient may reach 8 A during 5 µs. Consequently, switching at high frequencies with a shorted output
may destroy the circuit. If a short circuit condition is detected, stop switching the input and remove fault condition.

Thermal protection

The output of NJM3545 is equipped with a thermal shut-down function, that turns the outputs off at a chip (junction)
tenperature above typically 130°C.
Normal operation is resumed when the temperature has decreased about 20C.

Error functions

The Error indicating signal occurs on a separate pin. The complete error table is shown in figure 7.

The following conditions generate an error signal:
When the driver is activated and at least one of the following conditions has occurred:

• thermal overload

• short circuit to GND

• short circuit to V

• open circuit

An output current less than 8 mA might be detected as “open circuit”. Output currents larger than 8 mA and

less than 2 A will definitely not generate an error. The normal operational area is shown in figure 3.

Also when the driver is inactivated an Error indication can occur. That is if the output is shorted to GND. In figure
4 short circuit to GND Error state versus output voltage is shown.

When the Error-detection function is activated, the Error output is capable of sinking 8 mA, supporting direct
connection of an LED. The current has to be externally limited by a series resistor.

CC

Signal diagrams

The signal diagram in figure 8 shows the input signal and the resulting output signals for each error mode. For
details, see error table, figure 7.

VIN = Input voltage. Active = HIGH.
V

= Output voltage.

OUT

I

= Output current from driver.

OUT

V

= Error output voltage.

ERR

Error = LOW.

V

IN

V

OUT

*

I

OUT

V

Err

Normal
operation

Figure 8. Signal diagram

Overload or
short circuit

Short circuit
to GND

>130° <120°

Open circuit Over

Undefined

*

level

temperature

NJM3545

Low

High

Input level

Output voltage

V

CC

t

t

phl

of

Low

High

Input level

Output voltage

V

CC

t

t

plh

or

10 %

50 %

90 %

50 %

50 %

10 %

90 %

50 %

ON

OFF

■ ABSOLUTE MAXIMUM RATINGS

Parameter Pin no. Symbol Min Max Unit

Voltage

Supply voltage 1 V
Logic input voltage 5 V

CC

IN

Current

Logic input current 5 I
Continuous DC Operation output current TO-220 2 I
Error output current 4 I

IN
OUT
ERR

Temperature

Operating junction temperature (internally limited) T
Storage temperature T

J

S

Power Dissipation (Package Data)

Power dissipation at T

= 85°C, TO-220 package P

Case

D

ESD

ESD tolerance (Note 2) 2000 - V

■ RECOMMENDED OPERATING CONDITIONS

045V

-0.3 V

CC

V

-10 - mA

- 2000 mA

-10mA

- +140 °C

-40 +150 °C

-11W

Parameter Symbol Min Typ Max Unit

Supply voltage V
Output current TO-220 I
Operating junction temperature T
Error output current I

Supply
voltage

I

CC

Supply

NJM3545

I

I

I

IH

IL

IN

Input

V

IN

V

IH

V

I

Err

IL

Error

V

SAT Err

Fault
Detector

GND

Output

I

OUT

I

OMIN

V

I

CE SAT

OS

I

OL

+

C1

V

CC

OUT

j

Err

Load

CC

4.75 - 40 V

- - 2000 mA

-40 - +100 °C

-58 mA

Figure 9. Definition of symbols

Figure 10. Timing diagram, input vs.
output. V

= 24V

CC

NJM3545

■ ELECTRICAL CHARACTERISTICS

At 5 V ≤ VCC ≤ 40 V, -40°C ≤ TJ ≤ +100°C. Typical values are given at VCC = 24 V, TJ = 25°C

Parameter Symbol Conditions Min Typ Max Uni

General

Supply current I
Thermal shutdown T

CC

JS

Logic input

High level input voltage V
Low level input voltage V
High level input current I
Low level input current I

IH

IL
IH
IH

Outputs

Error output saturation voltage V
Output saturation voltage V
Output current shutdown I
Output current I

Err SAT
CE SAT

OS

OMIN

(not detected as open circuit)
Output leakage current I

OL

Clamping diode forward voltage I

Timing

Propagation time I
Output high to low (50%), t
Output low to high (50%), t
Rise time (10 to 90%), t
Fall time (90 to 10%), t

phl
plh

or
of

0 ≤ VIN ≤ 0.8 1.5 4 7 mA

- +130 - °C

2.0 - V

CC

V

-0.3 - 0.8 V

2.0 ≤ VIN ≤ V

CC

-920µA

0 ≤ VIN ≤ 0.8 -400 - - µA

I

= 5 mA - 0.2 1 V

Err

I

= 2 A - 1.4 1.8 V

OUT

2.0 ≤ VIN ≤ V

2.0 ≤ VIN ≤ V

0 V≤ V

= 2.0 A - 1.5 1.8 V

F

= 2 A

OUT

CC
CC

≤0.8 V. Output = 0 V -8 -6 -2 µA

IN

2.0 3.2 4.5 A

0.5 2 8 mA

- 1.5 3.0 µs

- 0.5 1.0 µs

- 0.2 0.5 µs

- 0.2 0.5 µs

■ THERMAL CHARACTERISTICS

Parameter Symbol Conditions Min Typ Max Unit

Thermal resistance Rth

Rth

TO-220 package, junction to case - 5 - °C/W

j-c

TO-220 package, junction to ambient - 60 - °C/W

J-A

Notes:

1. Currents are defined positive if flowing into, and negative if flowing out of a terminal. Voltages are defined

between terminal and ground.

2. ESD testing according to Human Body Model (C

= 100 pF, R

Zap

= 1500 Ω)

Zap

NJM3545

■ APPLICATIONS INFORMATION

Important application areas are:

• Programmable logic control systems

• Relay control

• Hydraulic valves

• Intelligent interfaces between microprocessors and loads

• Robot techniques

• Print head drivers

• High-current stepper motor drivers

Transient protection

1. Keep VCC and GND leads as short as possible.

2. Connect a filter capacitor close to the circuit. Recommended filter capacitor between VCC and GND is 6.8 µF, of
tantalum type. A ceramic capacitor in parallel will improve high frequency decoupling. Typical values range from

0.002 µF to 0.1 µF. In an application having a highly stable supply and short power leads to the driver a low
leakage electrolytic type can be used, which is less expensive.

3. Connect Input and Error via pull-up resistors to the appropriate logic supply level or VCC to obtain highest noise
immunity. See figure 11. The resistor R1 limits the current into the Error indicating pin. This current must not exceed
8 mA. R2 is a pull-up resistor which improves noise immunity at the Input. Pull-up current should not exceed the
sinking capacity of the controlling device output.

4. If several supply voltages are to be used, prefere a supply having separate ground leads. In this case the logic
ground and the power ground should be connected together at only one point, the ground pin of the driver.

Switch mode applications

The internal diodes are normally sufficient for clamping of transients caused by inductive load turn off. External
diodes may be necessary in PWM/switch mode applications, and when the terminals are externally accessible and
thereby exposed to an electrically noisy environment. Recommended diodes are BYV27/100,
BYV98/100, UF4001 or similar types with a trr < 100 ns and IF ≥ 1 A.

Error indication signal

When the circuit is switched on/off, a short pulse (t
This is a correct detection of an incorrect level during the rise and fall times of the output voltage. Consequently the
Error output should not be detected when switching on and off. An alternative is to low-pass filter at the Error output
at around 100 kHz.

Heat sinking

NJM3545N is packaged in a 5-pin TO 220 power package. The circuit GND is connected to the heat sink tab.
External heatsinking is achieved by mounting the package to a heat sink.

<10 µS for resistive loads) is generated at the Error output.

Err

Supply voltage +45 V max.

+ 5 V

R

5 kΩ

R

1

2

NJM3545

5

To logic

Voltage reference

V

cc

1

Input

TTL,

LS-TTL,

CMOS

µP,

controller

QRS

4

Error

Thermal
protection

Short-circuit to
V protection

cc

Short-circuit to
GND detection

Open circuit
detection

Figure 11. Typical application. Pin numbers refer to TO 220 package

Maximum allowable power dissipation [W]

6

TO 220 Package

NJM3545

Load

2

Output

+

6.8µF

3

GND

5

4

b

c

*

3

2

1

0

-40 -20 0 20 40 60 80 100 120 140

a. Ambient temperature. No heatsink. Rth =60°C/W.
b. Mounted on heatsink. Rth =20°C/W @ 4W.
c. Case temperature. Rth =5°C/W.

a

Temperature [°C]

J-A

J-A

J-C

Figure 12. Maximum allowable power
dissipation. TO 220 package

■ TYPICAL CHARACTERISTICS

NJM3545

Icc (mA)

10

-40°C < TJ< 100°C

8

6

4

2

0

010203040

Vcc (V)

Figure 13. Current consumption vs.
supply voltage at 0 V ≤ V

≤ 0.8 V

in

(Inactive output)

I

(mA)

ERR

20

TJ = 25°C

16

12

8

IF (A)

2.0

TJ = 25°C

1.6

1.2

0.8

0.4

2

3

0

3

1

9

50

0

0 0.4 0.8 1.2 1.6

2.0

VF (V)

Figure 14. Diode forward voltage drop
vs. forward current

I

(A)

OUT

5

4

3

= TJ= 25°C

I

(µ A)

IN
20

-40°C < TJ< 100°C

16

12

8

4

0

0 0.5 1.0 1.5 2.0

V

(V)

IN

Figure 15. Input current vs. input
voltage
5 V ≤ V

≤ 40 V

CC

I

(µA)

OL

-20

-16

-12

2.5

-40°C < TJ< 100°C

2

-8

4

0

02

468

V

(V)

ERR

10

Figure 16. Error output saturation
voltage vs. error current. VCC = 24 V

P

(W)

DIS

6

5

4

3

2

1

0

0 0.5 1.0 1.5 2.0

I

OUT

(A)

2.5

3.0

Figure 19. Power dissipation vs. output
current

1

0

0.4 0.8 1.2 1.6 2.0

V

CE SAT

(V)

Figure 17. Output saturation voltage vs.
output current. 5 V < V

913041

CC

IOS (A)

5

4

3

2

1

0

-40 -20 0 20 40

2.4

< 40 V

-4

0

010203040

Figure 18. Output leakage current vs
supply voltage. 0 V ≤ V
Output = 0 V

60

TJ(°C)

80 100 120

Figure 20. Typical output current shut-down vs. chip temperature. 5 V ≤ V

The specifications on this databook are only

given for information , without any guarantee
as regards either mistakes or omissions. The
application circuits in this databook are
described only to show representative usages
of the product and not intended for the
guarantee or permission of any right including
the industrial rights.

≤ 40 V

CC

50

V

(V)

CC

≤ 0.8 V

IN

913042