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The IMHC4 uses two Crystal Semiconductor sigma-delta codecs,
CS4231A, and delivers the A/D conversions to the destinations
via the TDM bus.
Output audio data is also transferred via the TDM bus.
Digital data is received from the sources by the codecs
and converted back to analog.
The IMHC4 includes autotracking, anti-aliasing and reconstruction
filters, and programmable gain and attenuation.
The IMHC4 features programmable sampling rates that are
multiples of the TDM subsystem frame rate, up to 48kHz.
Sample rate options directly supported by the host software
library are:
- 8 kHz
- 16 kHz
- 32 kHz
- 48 kHz
The IMHC4 codec supports six data formats:
- 8-bit ulaw
- 8-bit Alaw
- 8-bit linear
- 16-bit linear
- 8-bit dithered linear *
- 4-bit ADPCM *
* - formats not directly supported
by the host application library.
Analog input specifications:
- Single-ended or Differential (jumper selected)
- AC or DC coupled (jumper selected)
- Full scale input with 0db gain: 2V RMS (5.6 Vpp)
- Electret microphone: optionally populated bias resistor
(input must be single-ended and AC coupled)
- Input impedance (w/o optional bias resistor): approx 10 Kohms
- Input gain program selectable from 0 to 42.5 dB in 1.5 dB steps
Note: the A/D does not include telephony band-pass function.
Analog output specifications:
- Single-ended or Differential (jumper selected)
- DC coupled
- Full scale output with 0db attenuation: 2V RMS (5.6 Vpp)
- Output impedance: less than 10 ohms
- Capable of driving 32 ohm headphone
- Output attenuation program selectable from 0 to 94.5 dB in 1.5 dB steps
Software support: The host application library
includes function calls to control
IMHC4 operation.
General Specifications
| Product name |
IMHC4
|
| Codec chip |
CS4231A
|
| P/N code |
MPH1
|
| Channels |
4
|
| MTBF (kHr) |
486
|
| +5v power (A) |
0.1
|
| +12v power (A) |
0.2 |
| -12v power (A) |
0.1 |
| Max per V6M6 |
2
|
| V6M6 module sites |
A or C
|
| Max per C6M6 |
2
|
| C6M6 module sites |
A or C
|
| Size (inch) |
2.9 x 2.9
|
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