73M1866B-IMR/F Maxim Integrated Products, 73M1866B-IMR/F Datasheet - Page 46

• Manufacturer Part Number: 73M1866B-IMR/F
• Description: MICRODAA SGL PCM HIGHWAY 42-QFN
• Manufacturer: Maxim Integrated Products
• Series: MicroDAA™r

Specifications of 73M1866B-IMR/F

• Includes: PCM Highway
• Function: Data Access Arrangement (DAA)
• Interface: PCM, Serial, SPI
• Number Of Circuits: 1
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 42-VFQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Supply: -
• Power (watts): -

73M1866B/73M1966B Data Sheet
Similarly, the 16-bit data sample is received most significant bit first, beginning at the bit slot defined by
the RTS and RCS control registers. The reception lasts for 16 consecutive bit slots.
SR selects between 8 kHz and 16 kHz sampling rates. However, FS remains constant at 8 kHz.
Therefore, in 16 kHz sampling mode, two data samples are transmitted to (or received from) the PCM
highway starting at the bit slot dictated by the time and clock slot registers. In 16 kHz mode, either two or
four adjacent 8-bit time slots are used for two compressed 8-bit data samples or two linear 16-bit data
samples, respectively. The 16 kHz mode is enabled by setting SR=1 followed by SEL16K=1.
When switching to 16 kHz sampling rate and if the Call Progress Monitor function is being used, the
Line-Side Device needs to be reconfigured. See Section 7.7.
PCM highway interfaces are designed such that a device can transmit and receive to other devices on the
PCM highway. For example, Codec A will use a time slot assignment for its transmit to the PCM highway
and Codec B will assign its receiver to the same time slot. The time slot assignment is such that if Codec
A wants to transmit its data sample to Codec B, then Codec A transmit time/clock slot value is identical to
the Codec B receive time/clock slot value.
The 73M1x66B uses the DX signal pin to transmit to the PCM highway and the DR signal pin to receive
from the PCM highway. Figure 22 illustrates a typical example.
Larger systems may use buffers to interconnect multiple segments of the PCM highway (across line cards
for instance). In the 73M1x66B, Control TSC is used to control the tri-state mode of the transmit side of
the PCM highway as shown in Figure 23. TSC is asserted (active low) for the duration of the time slot
during which the 73M1x66B is transmitting to the PCM highway.
46
PCLK
DX
FS
DX
Codec A
DX
Codec A
Figure 23: Example of PCM Highway Interconnect for Typical Large Systems
DR
DR
TSC
TSC
MSB
Figure 22: Example of PCM Highway Interconnect
Figure 21: 16-bit Transmission Example
DX
DX
Codec B
Codec B
DR
DR
TSC
TSC
TSC Tri-State Control
Receive PCM Highway
Transmit PCM Highway
PCM Highway
DX
DX
Codec N
Codec N
DR
DR
TSC
TSC
LSB
From System
To System
To System
DS_1x66B_001
Rev. 1.6