Texas Instruments TAS3002 manual Analog Input/Output, 3.2.1Direct Analog Output

3 Analog Input/Output

The TAS3002 device contains a stereo 24-bit ADC with two single-ended inputs per channel. Selection of the A or B analog input is accomplished by setting a bit in the analog control register (ACR) by an I2C command. Additionally, the TAS3002 device has a stereo 24-bit digital-to-analog converter (DAC).

3.1 Analog Input

Figure 3−1 shows the technique and components required for analog input to the TAS3002 device. The maximum input signal must not exceed 0.7 Vrms. Selection of the above component values gives a frequency response from 20 Hz to 20 kHz at a sampling frequency of 48 kHz without alias frequency problems.

	2
	1200 pF	AINRP
	0.47 ∝F	AINRM
		RINA
	1		Voltage
1		RINB	Reference
	0.47 ∝F
			AINRP
	2		AINRM
	1200 pF	AINLP	24-Bit
	0.47 ∝F	AINLM	Stereo
			ADC
		LINA
	1
		LINB	AINLP
1
	0.47 ∝F
			AINLM
1	Analog Inputs − Use 0.47 ∝F for 20-Hz Cutoff		Input Select Command
			From Internal Controller

2Anti-Alias Capacitors for fS = 48 kHz

3Tie unused analog inputs to analog ground through 0.1-∝F capacitors.

Figure 3−1. Analog Input to the TAS3002 Device

3.2 Analog Output

3.2.1Direct Analog Output

The full scale analog output from the TAS3002 device is 0.707 Vrms. It is referenced to VCOM which is approximately 1.5 Vdc. VCOM must be decoupled with the network shown in Figure 3−2.

3−1