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Register Descriptions

TCA6507

WITH INTENSITY CONTROL AND SHUTDOWN

SCPS164B – MAY 2007 – REVISED NOVEMBER 2007

The Select0 register (register 0), Select1 (register 1), and Select2 register (register 2) configure the state of each

of the outputs (see Table 4) .

Table 4. Select2, Select1, and Select0 Register States

SELECT2

SELECT1

SELECT0

STATE

0

0

0

LED off (high impedance)

0

0

1

LED off (high impedance)

0

1

0

LED on steadily with maximum intensity value of PWM0 (ALD value or BRIGHT_F0 value)

0

1

1

LED on steadily with maximum intensity value of PWM1 (ALD value or BRIGHT_F1 value)

1

0

0

LED fully on (output low). Can be used as general-purpose output

1

0

1

LED on at brightness set by One Shot / Master Intensity register

1

1

0

LED blinking with intensity characteristics of BANK0 (PWM0)

1

1

1

LED blinking with intensity characteristics of BANK1 (PWM1)

Table 5. Register 0 (Select0 Register)

BIT

S0-7

S0-6

S0-5

S0-4

S0-3

S0-2

S0-1

S0-0

DEFAULT

0

0

0

0

0

0

0

(1)

X = Don't care

Table 6. Register 1 (Select1 Register)

BIT

S1-7

S1-6

S1-5

S1-4

S1-3

S1-2

S1-1

S1-0

DEFAULT

0

0

0

0

0

0

0

(1)

X = Don't care

Table 7. Register 2 (Select2 Register)

BIT

S1-7

S1-6

S1-5

S1-4

S1-3

S1-2

S1-1

S1-0

DEFAULT

0

0

0

0

0

0

0

(1)

X = Don't care

To use a P port as a general-purpose output, Select1 and Select0 registers must be set low (or 0), then the

inverse of the data written to the Select2 bit appears on the open-drain output.

The intensity of each bank of LEDs can be customized by programming six registers: Fade-On Time, Fully-On

Time, Fade-Off Time, First Fully-Off Time, Second Fully-Off Time, and Maximum Intensity registers. Each bank is

designed to produce two identical intensity pulses per blink cycle. Both pulses have the same fade-on, fully-on

and fade-off times, but independent fully-off times to achieve a double-blink effect when desired.

The Fade-On Time register (register 3) defines the time from the fully-off state to the fully-on state for the LED

per region A in Figure 7. The first four bits (C7–C4) in this register set the fade-on time for BANK1, and the next

four bits (C3–C0) set the fade-on time for BANK0. The data for each bank is a binary number between 0 and 15.

For BANK1, the MSB is bit C7, while the least significant bit (LSB) is bit C4. For BANK0, the MSB is bit C3 while

the LSB is bit C0. See Table 13 for more information.

Table 8. Register 3 (Fade-On Time Register)

BANK

BANK1

BANK0

BIT

C7

C6

C5

C4

C3

C2

C1

C0

DEFAULT

0

1

0

0

0

1

0

0

8

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