HC55185EVAL1 Intersil, HC55185EVAL1 Datasheet - Page 8

• Manufacturer Part Number: HC55185EVAL1
• Manufacturer: Intersil

PCM4 Configuration
Description
The PCM4 configuration verifies the AC transmission of the
HC55185 and CODEC. Any piece of test equipment capable
of PCM testing with digital and analog interfaces can be
used in this configuration.
Power Supply Connections
Power should be applied to the evaluation board using the
primary power cable. Either J5 or J6 may be used. Prior to
applying power, the voltage setting of each supply should be
verified. The power supplies should be turned off while
mating the primary power cable to the evaluation board.
Jumper Settings
All jumper settings are described below.
JUMPER
JP4
JP6
JP7
JP8
TABLE 4. PCM4 JUMPER POSITIONS
Connects the receive output of the CODEC (U6) to
the device receive input VRX. Signal path is AC
coupled.
Connects the device transmit output VTX to the
CODEC amplifier for transhybrid balance. Signal
path is AC coupled.
Connects the receive output of CODEC to
transhybrid amplifier, AC coupled by C1.
Inserting jumper set the CODEC to A-law coding.
Open sets the CODEC to -law coding. This must
match PCM test equipment coding scheme for
proper operation.
4-8
J3
J2
DESCRIPTION
J4
J1
S1
0
JP1
S2
0
J5
FIGURE 8. PCM4 CONNECTORS AND JUMPERS
JP2
S3
APP CKT
HC55185
1
JP3
Application Note 9814
S4
x
S5
1
J6
S6
JP4
0
JP6
JP5
CLOCK GENERATION & MUX
J7
JP9
Clock and Frame Sync
The clock and frame sync signals are driven at connectors
J13 and J12 respectively. The clock input is common to the
MCLK, BCLKT and BCLKR of the CODEC. The frame sync
input is common to the receive and transmit frame syncs,
FSR and FST, of the CODEC. These connections define
synchronous mode of operation.
Digital to Analog
The receive signal path is defined from the CODEC PCM
input to the HC55185 Tip and Ring outputs. The PCM4 tester
is capable of driving digital test signals on the PCM bus and
measuring the resultant signal at Tip and Ring. With this type
of capability, the full receive path can be evaluated. Typical
performance measurements include overall loss, gain
variation versus frequency, gain versus signal level and 2-wire
return loss. In addition fidelity measurements such as idle
channel noise and distortion are also performed.
Analog to Digital
The transmit signal path is defined from HC55185 Tip and
Ring interface to the CODEC PCM output. The same tests
performed for the receive path also apply to the transmit
path.
Digital to Digital
The digital to digital path is from the CODEC PCM input to
the CODEC PCM output. This signal path provides a
measure of the transhybrid balance for the line circuit. Most
other AC performance metrics are base on analog to digital
or digital to analog measurements. For proper transhybrid
measurements, verify jumper JP7 is inserted.
JP8
J8
JP10
APP CKT
CODEC
JP12
JP11
J9
J15
JP7
J10
J11
J12
J13
J14