TLC320AD545 Datasheet, PDF (16/37 Pages) Texas Instruments – Single Channel Data/Fax Codec

3.7 Interpolation Filter
The interpolation filter resamples the digital data at a rate of N times the incoming sample rate where N is the
oversampling ratio. The high-speed data output from this filter is then applied to the sigma-delta DAC.
3.8 Analog and Digital Loopbacks
The test capabilities include an analog loopback and digital loopback. The loopbacks provide a means of testing the
ADC/DAC channels and can be used for in-circuit system-level tests.
Analog loopback loops the DAC output back into the ADC input. Digital loopback loops the ADC output back into the
DAC input. Analog loopback is enabled by setting bit D4 in the control register 1. Digital loopback is enabled by setting
bit D5 high in control register 1. The analog loopback function tests only the codec portion of the device and does
not include the hybrid amplifier.
3.9 Software Power Down
The software power down resets all internal counters but leaves the contents of the programmable control registers
unchanged. The software power down feature is invoked by setting bit D6 high in control register 1. There is no
hardware power down function in the TLC320AD545.
3.10 Test Module
The test module serves the purpose of facilitating design verification test and simplifying factory production testing.
There are three input/output terminals (TEST1, TEST2 and TCLK) dedicated to implementing the test functions. The
function of these terminals is for factory self-test only and no connection (NC) should be made to either of these
terminals.
3.11 Power Supply Options
Option 1
Option 2
Option 3
ANALOG SUPPLY
(DAVDD)
5V
3.3 V
5V
DIGITAL SUPPLY
(DVDD)
5V
3.3 V
3.3 V
MONITOR SUPPLY
(MVDD)
5V
3.3 V
5V
3–2