CRD4412
1. SYSTEM OVERVIEW
The CRD4412 reference design is an excellent means for evaluating the CS4412 30 W digital amplifier power stage.
The board is designed to connect directly to the CRD4525 digital amplifier reference design for easy evaluation. Al-
ternatively, the CRD4412 may be used alone with all logic-level and power connections made through the CRD4412
interface header.
The CRD4412 schematic set is shown in Figure 3 through Figure 4. See the CRD4525 datasheet for more informa-
tion about the features and connections of the CRD4525.
1.1
Power
Power (VD, VP) must be supplied to the evaluation board through the CS4412 interface header (J2). All
voltage inputs must be referenced to ground, also provided through the CS4412 interface header.
See the CRD4412 Interface Header Signal Assignments table on page 7 for signal to pin assignments.
WARNING: Please refer to the CS4412 data sheet for allowable voltage levels.
1.2
1.3
CS4412 Digital TV Amplifier
The CS4412 is a 30 W quad half-bridge digital amplifier power stage. A complete description of the CS4412
is included in the CS4412 product data sheet.
External Data Headers
The evaluation board has been designed to allow interfacing with external systems via the headers J2, J4,
and J6. Figure 3 shows the headers’ electrical connections.
The 20-pin, 2 column header, J2, is included to interface with the CRD4525 digital amplifier reference de-
sign, and to interface with external sources when a CRD4525 is not connected. All necessary signals, pow-
er, and ground are presented on this header. See Figure 3 for complete connectivity information.
The 4-pin, 2 column header, J4, provides access to the CS4412’s thermal warning signal and the CS4525’s
DLY_SDIN/EX_TWR signal. When a CRD4525 is attached, a shunt can be placed across these signals to
deliver the CS4412’s thermal warning signal to the CS4525’s external thermal warning input. Alternatively,
this header can be used to connect the CS4412’s thermal warning output to another device, and to drive an
external serial audio data source into the CS4525. A single ground column is provided to maintain signal
integrity in this configuration.
The 4-pin, 2 column header, J6, provides access to the CS4412’s over-current error signals and the
CS4525’s DLY_SDOUT signal. When a CRD4525 is attached, this header can be used to connect the
CS4412’s over-current error signals to another device, and to connect the CS4525’s delay serial audio data
output to an external device. A single ground column is provided to maintain signal integrity in this configu-
ration.
1.4
Stereo/Mono Selection
A 3-pin header (J1) is included to select between stereo and mono operation. The position of the shunt
placed across this header determines whether discrete PWM signals are routed to the full-bridge input pairs,
or whether a single PWM signal is routed to both full-bridge input pairs.
It should be noted that when mono mode is selected, the outputs may be wired in parallel to achieve parallel
full-bridge operation. See Section 1.5 for more information.
DS749RD1
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