Philips Semiconductors Linear Products

Product specification

NE587

LED decoder/driver

August 31, 1994

535

TYPICAL PERFORMANCE CURVES

IOUT

(mA)

Supply Current vs Supply Voltage

Output Current vs Output Voltage

Normalized Output Current vs

Normalized Output Current vs Supply

Maximum Power Dissipation vs

Temperature

Output Current vs Program Resistor

40.0

35.0

30.0

25.0

20.0

4.0

4.4

4.8

5.2

5.6

6.0

6.4

VCC (VOLTS)

ICC

(mA)

RP = 1kΩ

VOUT = 2V

ALL OUTPUTS “ON”

(0

°C)

(25

°C)

(70

°C)

40.0

30.0

20.0

10.0

IOUT

0

1.0

2.0

3.0

4.0

5.0

VOUT (VOLTS)

(70

°C)

(0

°C)

(25

°C)

RP = 1kΩ

(%)

IOUT

TEMP (

°C)

110.0

105.0

100.0

95.0

90.0

10 20 30 40

50 60 70 80

105

102

100

98

95

4.0

4.5

5.0

5.5

6.0

(%)

NE587

RP = 1kΩ

NE587

VCC (VOLTS)

1000

800

600

400

200

0

0

25

50

75

TA (°C)

(mW)

PD

50.0

40.0

30.0

20.0

10.0

0.0

0

2.0

4.0

6.0

8.0

10.0

VCC = 5.0V

VOUT = 2V

TA = (25°C)

RP (kΩ)

(mA)

IOUT

These voltages are all for single-diode displays. Some early red

displays had 2 series LEDs per segment; hence the forward voltage

drop was around 3.5V.

Thus, a maximum power dissipation calculation when all segments

are on, is:

P

(V

V

x K

However, the average power dissipation will be considerably less

than this. Assuming 5 segments are on (the average for all output

code combinations), then

Operating temperature range limitations can be deduced from the

power dissipation graph. (See Typical Performance Characteristics.)

Figure 5. Driving a Single Digit

VS

VCC

D3

D2

D1

D0

IP

Decoupling capacitor on VCC should be 0.01µF ceramic.

LE

RBI

RBO

0.01

µF

NOTE:

NE587

a

b

c

d

e

f

g