ISSUE 2 - APRIL 2002

ZXCD1000

8

Class D Mono Open Loop solution (Bridge Tied Load - BTL) Solution - Demonstration board

The circuit design shown in figure 4 is available as a

demonstration board to enable evaluation of the circuit

excellent performance. Full bill of materials (BOM) and

Gerber files are also available. The demonstration

board part number is ZXCD1000EVMOL. Layout and

component selection are critical to maximising

performance from this solution, the demonstration

board and circuit can be used as a guide to facilitate

design of production circuits. Zetex applications can

advise if any circuit modifications are required for

specific requirements.

The board can be used to demonstrate the ZXCD

amplifier capability with output power typically of 25W

into 4

or 8

load depending on chosen supply

voltage. Operating instructions are included in the

demonstration board literature.

A very important feature of the Zetex solution is that

the residual distortion is almost totally free of any

crossover artifacts. This lack of crossover distortion

sets the ZXCD1000 solutions quite apart from most

other presently available low cost solutions, which in

general suffer from severe crossover distortion

problems.

It is well known that this kind of distortion is particularly

unpleasant to the listener. The two scope traces of

Figure 7 clearly show the lack of such artifacts with the

Zetex solution

Figure 7a

ZETEX Class D Solution. (10W into 4

Ω)

Note lack of Crossover Artifacts

Figure 7b

Typical Class D Solution.

Note Large Crossover Artifacts

Figure 6

Mono solution demonstration board