TSL3301CL

102 × 1 LINEAR OPTICAL SENSOR ARRAY

WITH ANALOG-TO-DIGITAL CONVERTER

TAOS141 − JULY 2011

8

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Copyright

E 2011, TAOS Inc.

The LUMENOLOGY

r Company

www.taosinc.com

OPERATION

Initialization Sequence

After powering on the device, a minimum of 10 clocks with SDIN held high must be received by the TSL3301CL

to clear the receiver logic so that a start bit will be detected correctly. The control logic may then be cleared by

either issuing an IRESET command (break character) or 3 RESET (0x1b) commands. An additional 30 clocks

must be received by the device to assure the state of SDOUT.

Sleep Mode

The device can be put into a power down or sleep mode by writing a 0x10 to the mode register. This turns off

all the analog circuitry on the chip. Normal operation is restored by writing a 0x00 to the mode register. The

Note that putting the device in the sleep mode does not affect the logic states of the machine. If, for example,

a READPixel command is issued, the device will respond but the resulting data will be meaningless. Also note

that 0x00 and 0x10 are the only two legitimate user programmable values for the single-chip version of the

TSL3301CL. Other values may put the device into a non-operational mode.

Imaging

After powering up the device and completing the initialization sequence, it is necessary to allow a minimum of

1 millisecond for the internal analog circuitry to settle. This delay is also required when coming out of the sleep

mode.

Issuing a STARInt (0x08) command will release the pixel integrators from the reset state. After an appropriate

delay to integrate the image, the pixel data may be sampled by issuing a SAMPLEInt (0x10) command and then

read out by issuing a READPixel (0x02) command.

A STARTInt command can be issued anytime after the SAMPLEInt command is issued to start another cycle.

Thus, it is possible to be reading out one sample while integrating the next. However, the sampled data from

the previous SAMPLEInt must be completely read out before the next SAMPLEInt command is issued.

The compound commands READHold (0x12) and READHoldNStart ((0x16) are shortcut commands to simplify

the imaging sequence.

It is important to note that a pixel reset sequence is initiated with the receipt of a STARTInt or READHoldNStart

command. The next integration sequence cannot start until the pixel reset sequence has been completed, which

requires 22 clocks AFTER the receipt of one of these commands. These clocks can also be used to clock

commands or data into or out of the device.