The API840N eliminates the need of complicated circuitry in voice playback (Figure 1) but still achieves high voice quality. Sounds such as human speech, animal sounds, musical sounds, and even special sound effects can be synthesized. Devices can be cascaded to achieve longer voice duration (Figure 3). Two devices can be configured in parallel (Figure 4) in order to achieve signal mixing without an external mixer allowing speeches to be mixed with background music synthesis from two different chips. The instant programming nature of the API840N allows a very short production turnaround time. There are no NRE charges that are usually required with conventional voice ROMs. Users now can apply a voice synthesis function as an additional feature to their products even when production volume is relatively small. It is also ideal for trial or engineering prototyping. As a result, the initial investment is minimal and the risk in the product development phase is reduced.