5 Description (continued)

The record path of the TLV320AIC34 contains integrated microphone bias, digitally controlled four-channel microphone preamplifier, and automatic gain control (AGC), with mix or mux capability among the multiple analog inputs. Programmable filters are available during record which can remove audible noise that can occur during optical zooming in digital cameras. The playback path includes mix or mux capability from the four-channel DAC and selected inputs, through programmable volume controls, to the various outputs.

The TLV320AIC34 contains eight high-power output drivers as well as six line-level output drivers. The high-power output drivers are capable of driving a variety of load configurations, including up to eight channels of single-ended 16-Ω headphones using ac-coupling capacitors, or four channels in a capless output configuration. In addition, for codec A, pairs of drivers can be used to drive mono or stereo 8-Ω speakers directly in a BTL configuration at 500 mW per channel.

The four-channel audio DAC supports sampling rates from 8 kHz to 96 kHz and includes programmable digital filtering in each path for 3D, bass, treble, midrange effects, speaker equalization, and de-emphasis for 32-kHz, 44.1-kHz, and 48-kHz rates. The four-channel audio ADC supports sampling rates from 8 kHz to 96 kHz and is preceded by programmable gain amplifiers providing up to 59.5-dB analog gain for low-level microphone inputs. The TLV320AIC34 provides an extremely high range of programmability for both attack (8 to 1,408 ms) and for decay (0.05 to 22.4 seconds). This extended AGC range allows the AGC to be tuned for many types of applications.

For battery saving applications where neither analog nor digital signal processing is required, the device can be put in a special analog signal pass-through mode. This mode significantly reduces power consumption, as most of the device is powered down during this pass through operation.

The serial control bus supports normal-speed and fast I²C protocols, whereas the dual serial audio data busses are programmable for I²S, left- or right-justified, DSP, PCM, or TDM mode. Two highly programmable PLLs are included for flexible clock generation and support for all standard audio rates from a wide range of available MCLK_x frequencies, varying from 512 kHz to 50 MHz, with special attention paid to the most popular cases of 12-MHz, 13-MHz, 16-MHz, 19.2-MHz, and 19.68-MHz system clocks.

The TLV320AIC34 operates from an analog supply of 2.7 V to 3.6 V, a digital core supply of 1.65 V to 1.95 V, and a digital I/O supply of 1.1 V to 3.6 V. The device is available in a 6-mm × 6-mm, 87-ball NFBGA package.