TLC5902

LED DRIVER

SLLS382 – DECEMBER 1999

17

POST OFFICE BOX 655303

PRINCIPLES OF OPERATION

0

10

20

30

40

50

60

70

80

90

0.1

1

10

NOTE: The output current is at 16 bit output.

When 8-bit output, it will be the current of sum of two

outputs. This sum current should be set up with the range

of 10 mA to 120 mA. The resistor, RIRF, should be located

as close as possible to IREF terminal to eliminate the noise

influence.

Conditions : V

I

V

R

38

R

47

I

R(IREF) – kΩ

Figure 4. Current on Constant Current Output vs External Resistor

RIREF = 4.70 k

0

1.0

0.2

0

0.4

0.6

0.8

100

10

0.1

0.3

0.5

0.7

0.9

20

30

40

50

60

70

80

90

RIREF = 2.35 k

RIREF = 1.57 k

RIREF = 1.18 k

RIREF = 940

RIREF = 780

RIREF = 670

R

IREF = 590

Minimum voltage applied

Ω

Ω

Ω

Ω

Ω

Ω

Ω

Ω

VO – Output Voltage –V

NOTE: VCCLOG = VCCANA = PVCC = 5 V, TA = 25°C.

Figure 5. Current on Constant Current Output vs Voltage Applied To Constant Current Output Terminal