One limitation of the standard bridge connection is that the load cannot be returned to ground. This can be circumvented by op-

erating the bridge with floating supplies, as shown above. For single-ended drive, either input can be grounded.

This circuit shows how two amplifiers can be cascaded to double output swing. The advantage over the bridge is that the output

can be increased with any number of stages, although separate supplies are required for each.

will provide safe-area protection for the external transistors. Voltage gain is about thirty.

DS008704-16

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