TLC3574_14 Datasheet, PDF (32/50 Pages) Texas Instruments – 14-Bit Resolution for TLC3574/78, 12-Bit for TLC2574/2578

TLC3574, TLC3578, TLC2574, TLC2578
5ĆV ANALOG, 3Ć/5ĆV DIGITAL, 14Ć/12ĆBIT, 200ĆKSPS, 4Ć/8ĆCHANNEL
SERIAL ANALOGĆTOĆDIGITAL CONVERTERS WITH ±10ĆV INPUTS
SLAS262C − OCTOBER 2000 − REVISED MAY 2003
FIFO operation
ADC
×8
FIFO
Serial
SOD
76543210
FIFO Full
FIFO 1/2 Full
FIFO 3/4 Full
FIFO 1/4 Full
FIFO Threshold Pointer
Figure 20. FIFO Structure
FIFO operation (continued)
The device has an 8-level FIFO that can be programmed for different thresholds. An interrupt is sent to the host
after the preprogrammed threshold is reached. The FIFO is used to store conversion results in mode 01, 10,
and 11, from either a fixed channel or a series of channels according to the preprogrammed sweep sequence.
For example, an application may require eight measurements from channel 3. In this case, if the threshold is
set to full, the FIFO is filled with 8 data conversions sequentially taken from channel 3. Another application may
require data from channel 0, 2, 4, and 6 in that order. The threshold is set to 1/2 full and sweep sequence is
selected as 0−2−4−6−0−2−4−6. An interrupt is sent to the host as soon as all four data conversions are in the
FIFO. FIFO is reset after power on and WRITE CFR operation. The contents of the FIFO are retained during
autopower down.
Autopower-Down Mode: The device enters the autopower-down state at the end of conversion. The power
current is about 20 µA if SCLK stops, and 120 µA maximum if SCLK is running. Active CS , FS, or CSTART
resumes the device from power-down state. The bipolar input current is not turned off when device is in
power-down mode.
The configuration register is not affected by the power-down mode but the SWEEP operation sequence must
be started over again. All FIFO contents are retained in power-down mode.
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