TI TWL6041BYFFR

TWL6041 is a highly integrated audio codec that provides analog audio codec functionality for portable applications. The device features multiple audio analog inputs and outputs, along with microphone bias and accessory detection capabilities. It connects to the OMAP4 host processor via a proprietary PDM interface for audio data communication, enabling partitioning and optimized power consumption and performance. Multi-channel audio data is multiplexed onto a single line for downlink (PDML) and uplink (PDMUL).

The OMAP4 device provides five PDM audio input channels (DL0–DL4) to the TWL6041 device. Channels DL0–DL3 are connected to 4 parallel DACs multiplexed to stereo headset (HSL, HSR), stereo speaker (HFL, HFR), and earpiece (EAR) or stereo line output (AUX, AUXR).

The stereo headset path features a low-power (LP) mode operating from a 32kHz sleep clock to achieve over 100 hours of MP3 playback time. When using the system clock input and DAC path high-performance (HP) mode, an exceptional dynamic range of 104dBA is achieved. The Class-AB headphone driver provides a 1 Vrms output with a center ground for capacitor-free connection to headphones, reducing system size and cost. The earpiece driver is a differential Class-AB driver capable of 2 Vrms into a typical 32Ω load or 1.4Vrms into a typical 16Ω load.

The stereo speaker path provides 1.5W per channel of filterless Class-D output capability, with support for 4Ω loads. To maximize output power, connection to an external boost device is supported. In addition, the speaker driver supports hearing aid coil loads.

For vibrator and haptic feedback support, the TWL6041 provides two PWM channels, each driven by independent input signals from either DL4 or I2C. The vibration driver features differential H-bridge outputs with fast acceleration and deceleration of vibration motors. External drivers for hearing aid coils or piezoelectric speakers requiring high voltage can be connected to the line output.

The TWL6041 supports three differential microphone inputs (MMIC, HMIC, and SMIC) and one stereo line input (AFML, AFMR) multiplexed to two parallel ADCs. The PDM output from the ADCs is routed to the OMAP4 processor via UL0 and UL1. The AFML and AFMR inputs can be looped back to the analog outputs (LB0, LB1).

Two LDOs provide a 2.1V bias voltage for analog microphones (MBIAS and HBIAS). The maximum output current for each analog bias is 2mA, allowing up to 2 microphones per bias. Two LDOs provide 1.8V to 1.85V bias voltage for digital microphones (DBIAS1 and DBIAS2). A single bias voltage generator can simultaneously bias multiple digital microphones with a maximum total output current of 10mA.

The TWL6041 device features an integrated negative charge pump and two LDOs (HS LDO and LS LDO) for high PSRR. The only required external supply is 2.1V, provided by the 2.1V DC-DC converter of the TWL6030/6032 PMIC in the OMAP4 system. By powering the audio subsystem from a low-power, low-noise 2.1V DC-DC converter, high dynamic range and high output swing can be achieved at the headphone output. All other power inputs can be connected directly to the battery or the system 1.8V I/O.

Two integrated PLLs support device operation at 12MHz, 19.2MHz, 26MHz, and 38.4MHz system clock (MCLK), or, in LP playback mode, at a 32kHz sleep clock (CLK32K). For all channels, frequency planning is based on a 48kS/s audio data rate, and the host processor uses a sample rate converter to interface with different sample rates (e.g., 44.1kHz). For the specific case of low-power audio playback, the TWL6041 supports 44.1kS/s and 48kS/s rates. Transitions between sample rates or input clocks are seamless.

Accessory plug/unplug detection (PLUGDET) is supported. Some headsets have a manual switch that can send a send/end signal to the terminal via the microphone input pin. This feature is supported by periodic accessory button press detection to significantly reduce current consumption in sleep mode. The detection period can be programmed according to system requirements.

When connected to the OMAP4/OMAP5 platform, the TWL6041BSRS incorporates SRS audio effects, SRS preprocessing solutions, and SRS TruMedia as standard features for Android ICS.

• Four audio DAC channels
• Capless stereo headphone driver – up to 104dB dynamic range (DR) – power scaling for balance between performance and power consumption
• Per-channel stereo 8Ω, 1.5W speaker driver with simultaneous 4Ω differential earpiece driver and stereo line output
• Two audio ADC channels – 96dBA SNR
• 4 audio inputs: – Three differential microphone inputs – Stereo line input and FM input
• Two oscillator and haptic feedback channels – Differential H-bridge driver
• 2 low-noise analog microphone bias outputs
• 2 digital microphone bias outputs
• Analog low-power loop from line input to headphone and speaker outputs
• Dual PLL with flexible clocking: – 32kHz sleep clock input for system low-power playback mode; 12MHz, 19.2MHz, 26MHz, 38.4MHz system clock input
• Accessory insertion/removal detection and accessory button press detection
• Integrated power supplies: – Negative charge pump for capless headphone driver; dual LDOs for high PSRR
• I2C control; thermal protection – Host interrupt; supply voltages: – Analog voltage: 2.1V; digital I/O voltage: 1.8V – Battery voltage: 2.3V to 5.5V
• 3.8mm × 3.8mm, 81-ball WCSP package

• Mobile phones and smartphones
• MP3 players
• Handheld devices