msm7728 Oki Semiconductor, msm7728 Datasheet - Page 5

• Manufacturer Part Number: msm7728
• Description: Single Rail Linear Codec
• Manufacturer: Oki Semiconductor

¡ Semiconductor
MSM7728
SPKP, SPKN
These pins are used for speaker driving.
The SPKN output is reversed in phase against the SPKP output when the gain is 1.
The receive output signal amplitude is 2.2V
at maximum.
PP
These outputs swing around the SG potential (signal ground potential, V
/2) and can drive the
DD
minimum 0.6kW load in pushpull driving mode.
The maximum output amplitude is 4.4V
in pushpull driving mode (a load is inserted between
PP
SPKN and SPKP).
Control data from the processor interface allows selecting the D/A conversion output, PB tone
output, or service tone output and also can provide a level control and mute control. When SPK
is turned off, the SG potential is output with high resistance.
EAR
Analog output for external accessary circuit.
This output swings around the SG potential and can drive the minimum 0.6kW against the SG
potential.
Control data from the processor interface allows selecting the D/A conversion output, PB tone
output, or service tone output and also can provide a level control and mute control. When EAR
is turned off, the SG potential is output with high resistance.
BCLK
Shift clock signal input for PCMIN and PCMOUT.
The frequency is equal to the data signaling rate.
SYNC
Synchronizing signal input.
In the transmit section, the PCM output signal from the PCMOUT pin is output synchronously
with this synchronizing signal. This synchronizing signal triggers the PLL and synchronizes all
timing signals of the transmit section.
In the receive section, 14 bits required are selected from serial input of PCM signals on the PCMIN
pin by the synchronizing signal.
Signals in the receive section are synchronized by this synchronizing signal. This signal must be
synchronized in phase with the BCLK.
When this signal frequency is 8 kHz, the transmit and receive paths have the frequency
characteristics specified by ITU-T G. 714. The frequency characteristics for 8 kHz are specified in
this data sheet.
For different frequencies of the SYNC signal, the frequency values in this data sheet should be
translated according to the following equation:
Frequency values described in the data sheet
¥ the SYNC frequency values to be actually used
8 kHz
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