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SOUT

15 pF

OUTn

51

Ω

15 pF

XDOWN

470 k

Ω

I

MAX +

V

IREF

R

IREF

40

(1)

I

Outn +

I

MAX

DCn

127

(2)

TLC5922

SLVS486 – SEPTEMBER 2003

PARAMETER MEASUREMENT INFORMATION

Figure 4. Test Circuit for Tr0, Tf1, Td0, Td1

Figure 5. Test Circuit for Tr1, Tf1, Td2, Td3, Td5, Td6

Figure 6. Test Circuit for Td4

PRINCIPLES OF OPERATION

Setting Constant-Current Value

scaling factor of 40 to set the maximum output current for all outputs. The voltage on IREF is set by an internal

band gap with a nominal value of 1.22V. The maximum programmable output current is set by Equation 1:

where:

Setting Dot-Correction

The TLC5922 has the capability to adjust the brightness of each channel, OUT0,...,OUT15. This capability is

called dot-correction. The external processor programs each of the 16 channels of the TLC5922 with a 7 bit word

that adjusts each respective output from 0% to 100% of the maximum output current, Imax. The 7 bits provides

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