ST TDA7440 User Manual

TDA7440

TONE CONTROL DIGITALLY CONTROLLED AUDIO PROCESSOR

1 FEATURES

INPUT MULTIPLEXER

–4 STEREO INPUTS

–SELECTABLE INPUT GAIN FOR OPTIMAL ADAPTATION TO DIFFERENT SOURCES

ONE STEREO OUTPUT

TREBLE AND BASS CONTROL IN 2.0dB STEPS

VOLUME CONTROL IN 1.0dB STEPS

TWO SPEAKER ATTENUATORS:

–TWO INDEPENDENT SPEAKER CONTROL IN 1.0dB STEPS FOR BALANCE FACILITY

–INDEPENDENT MUTE FUNCTION

ALL FUNCTION ARE PROGRAMMABLE VIA SERIAL BUS

2 DESCRIPTION

The TDA7440D is a volume tone (bass and treble) balance (Left/Right) processor for quality audio applications in Hi-Fi systems.

Figure 1. Package

SO-28
Table 1. Order Codes
Order code		Package
TDA7440D		SO-28
TDA7440D013TR		Tape & Reel

Selectable input gain is provided. Control of all the functions is accomplished by serial bus.

The AC signal setting is obtained by resistor networks and switches combined with operational amplifiers.

Thanks to the used BIPOLAR/CMOS Technology, Low Distortion, Low Noise and DC stepping are obtained

Figure 2. Block Diagram

			MUXOUTL	INL	TREBLE(L)	BIN(L)	BOUT(L)
4			8	9	18	14	15
L-IN1
	100K					RB
5
L-IN2
	100K
6		G	VOLUME		TREBLE	BASS	SPKR ATT		27
								LEFT	LOUT
L-IN3
	100K
7
L-IN4
	100K								21
		0/30dB
					I2CBUS DECODER + LATCHES				SCL
3		2dB STEP							22
									SDA
R-IN1									20
	100K								DIG_GND
2
R-IN2
	100K	G	VOLUME		TREBLE	BASS	SPKR ATT		26
								RIGHT	ROUT
1
R-IN3								VREF
	100K
28									24
								SUPPLY	VS
R-IN4		INPUT MULTIPLEXER							25
	100K					RB			AGND
		+ GAIN
			10	11	19	12	13	23
			MUXOUTR	INR	TREBLE(R)	BIN(R)	BOUT(R)	CREF	D98AU883

REV. 4

April 2010

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TDA7440

Figure 3. Pin Connection (Top view)

R_IN3			28
	1				R_IN4
R_IN2		2	27		LOUT
R_IN1		3	26		ROUT
L_IN1		4	25		AGND
L_IN2		5	24		VS
L_IN3	6		23		CREF
L_IN4	7		22		SDA
MUXOUTL	8		21		SCL
IN(L)	9		20		DIG-GND
MUXOUT(R)	10		19		TREBLE(R)
IN(R)	11		18		TREBLE(L)
BIN(R)	12		17		N.C.
BOUT(R)	13		16		N.C.
BIN(L)	14		15		BOUT(L)
			D98AU884

Table 2. Absolute Maximum Ratings

Symbol	Parameter	Value	Unit
VS	Operating Supply Voltage	10.5	V
Tamb	Operating Ambient Temperature	0 to 70	°C
Tstg	Storage Temperature Range	-55 to 150	°C

Table 3. Thermal Data

Symbol	Parameter	Value	Unit
Rth j-pin	Thermal Resistance Junction-pins	85	°C/W

Table 4. Quick Reference Data

Symbol	Parameter	Min.	Typ.	Max.	Unit
VS	Supply Voltage	6	9	10.2	V
VCL	Max. input signal handling	2			Vrms
THD	Total Harmonic Distortion V = 1Vrms f = 1KHz	0.01	0.1	%
S/N	Signal to Noise Ratio Vout = 1Vrms (mode = OFF)		106		dB
SC	Channel Separation f = 1KHz		90		dB
	Input Gain in (2dB step)	0		30	dB
	Volume Control (1dB step)	-47		0	dB
	Treble Control (2dB step)	-14		+14	dB
	Bass Control (2dB step)	-14		+14	dB
	Balance Control 1dB step	-79		0	dB
	Mute Attenuation		100		dB

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Table 5. Electrical Characteristcs

Refer to the test circuit Tamb = 25°C, VS = 9V, RL = 10KΩ, RG = 600Ω, all controls flat (G = 0dB), unless otherwise specified.

Symbol	Parameter	Test Condition	Min.	Typ.	Max.	Unit
SUPPLY
VS	Supply Voltage		6	9	10.2	V
IS	Supply Current		4	7	10	mA
SVR	Ripple Rejection		60	90		dB
INPUT STAGE
RIN	Input Resistance		70	100	130	KΩ
VCL	Clipping Level	THD = 0.3%	2	2.5		Vrms
SIN	Input Separation	The selected input is grounded	80	100		dB
		through a 2.2µ capacitor
Ginmin	Minimum Input Gain		-1	0	1	dB
Ginman	Maximum Input Gain		29	30	31	dB
Gstep	Step Resolution		1.5	2	2.5	dB
VOLUME CONTROL
Ri	Input Resistance		20	33	50	KΩ
CRANGE	Control Range		45	47	49	dB
AVMAX	Max. Attenuation		45	47	49	dB
ASTEP	Step Resolution		0.5	1	1.5	dB
EA	Attenuation Set Error	AV = 0 to -24dB	-1.0	0	1.0	dB
		AV = -24 to -47dB	-1.5	0	1.5	dB
ET	Tracking Error	AV = 0 to -24dB		0	1	dB
		AV = -24 to -47dB		0	2	dB
VDC	DC Step	adjacent attenuation steps from		0	3	mV
		0dB to AV max		0.5		mV
Amute	Mute Attenuation		80	100		dB
BASS CONTROL (1)
Gb	Control Range	Max. Boost/cut	+12.0	+14.0	+16.0	dB
BSTEP	Step Resolution		1	2	3	dB
RB	Internal Feedback Resistance		33	44	55	KΩ
TREBLE CONTROL (1)
Gt	Control Range	Max. Boost/cut	+13.0	+14.0	+15.0	dB
TSTEP	Step Resolution		1	2	3	dB
SPEAKER ATTENUATORS
CRANGE	Control Range		70	76	82	dB
SSTEP	Step Resolution		0.5	1	1.5	dB
EA	Attenuation Set Error	AV = 0 to -20dB	-1.5	0	1.5	dB
		AV = -20 to -56dB	-2	0	2	dB
VDC	DC Step	adjacent attenuation steps		0	3	mV
Amute	Mute Attenuation		80	100		dB

NOTE1:

1)The device is functionally good at Vs = 5V. a step down, on Vs, to 4V does’t reset the device.

2)BASS and TREBLE response: The center frequency and the response quality can be chosen by the external circuitry.

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Table 5. Electrical Characteristcs (continued)

Refer to the test circuit Tamb = 25°C, VS = 9V, RL = 10KΩ, RG = 600Ω, all controls flat (G = 0dB), unless otherwise specified.

Symbol	Parameter	Test Condition	Min.	Typ.	Max.	Unit
AUDIO OUTPUTS
VCLIP	Clipping Level	d = 0.3%	2.1	2.6		Vrms
RL	Output Load Resistance		2			KΩ
RO	Output Impedance		10	30	50	Ω
VDC	DC Voltage Level		3.5	3.8	4.1	V
GENERAL
ENO	Output Noise	All gains = 0dB;		5	15	µV
		BW = 20Hz to 20KHz flat
Et	Total Tracking Error	AV = 0 to -24dB		0	1	dB
		AV = -24 to -47dB		0	2	dB
S/N	Signal to Noise Ratio	All gains 0dB; VO = 1Vrms	95	106		dB
SC	Channel Separation Left/Right		80	100		dB
d	Distortion	AV = 0; VI = 1Vrms		0.01	0.08	%
BUS INPUT
VIL	Input Low Voltage				1	V
VIH	Input High Voltage		3			V
IIN	Input Current	VIN = 0.4V	-5	0	5	µA
VO	Output Voltage SDA	IO = 1.6mA		0.4	0.8	V
	Acknowledge

Figure 4. Test Circuit

						5.6nF	5.6K
							100nF	100nF
				2.2 F
			MUXOUTL	INL	TREBLE(L)		BIN(L)	BOUT(L)
L-IN1	4			8	9	18	14	15
0.47 F		100K					RB
L-IN2	5
0.47 F		100K
L-IN3	6		G	VOLUME		TREBLE	BASS	SPKR ATT	27	LOUT
								LEFT
0.47 F		100K
L-IN4	7
0.47 F		100K							21
			0/30dB							SCL
						I2CBUS DECODER + LATCHES			22
R-IN1	3		2dB STEP							SDA
									20
										DIG_GND
0.47 F		100K
R-IN2	2
0.47 F		100K	G	VOLUME		TREBLE	BASS	SPKR ATT	26	ROUT
								RIGHT
R-IN3	1							VREF
0.47 F		100K
R-IN4	28								24	VS
								SUPPLY	25
			INPUT MULTIPLEXER
0.47 F		100K					RB			AGND
			+ GAIN
				10	11	19	12	13	23
			MUXOUTR	INR	TREBLE(R)		BIN(R)	BOUT(R)	CREF	D98AU885
				2.2 F			100nF	100nF
						5.6nF			10 F
							5.6K

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3 APPLICATION SUGGESTIONS

The first and the last stages are volume control blocks. The control range is 0 to -47dB (mute) for the first one, 0 to -79dB (mute) for the last one. Both of them have 1dB step resolution. The very high resolution allows the implementation of systems free from any noisy acoustical effect.

The TDA7440D audioprocessor provides 3 bands tones control.

3.1 Bass Stage

Several filter types can be implemented, connecting external components to the Bass IN and OUT pins.

The fig.5 refers to basic T Type Bandpass Filter starting from the filter component values (R1 internal and R2,C1,C2 external) the centre frequency Fc, the gain Av at max. boost and the filter Q factor are computed as follows:

	FC	=		1
			2------------------	π ----------------------------------------------R1 R2 C1 C2-
	AV =		R2 C2 + R2 C1 + Ri C1
			---------------------------------------------------------------	R2 C1 + R2 C2

	Q =	R1 R2 C1 C2
		------------------------------------------------- R2 C1	+ R2 C2

Viceversa, once Fc, Av, and Ri internal value are fixed, the external components values will be:

C1 =	AV – 1	C2 =	Q2 C1	R2 =	AV – 1 – Q2
	2-----------------------------------------π FC Ri Q		A-----------------------------V – 1 – Q2		2----------------------------------------------------------------------π C1 FC (AV – 1) Q

Figure 5.

	Ri internal
IN	OUT
C1	C2
	R2
	D95AU313

Treble Stage

The treble stage is a high pass filter whose time constant is fixed by an internal resistor (25KΩ typical) and an external capacitor connected between treble pins and ground.

Typical responses are reported in Figg. 14 to 17.

CREF

The suggested 10mF reference capacitor (CREF) value can be reduced to 4.7mF if the application requires faster power ON.

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Figure 6. THD vs. frequency										Figure 9. Bass response

Ri = 44kΩ

C9 = C10 = 100nF (Bout, Bin)

R3 = 5.6kΩ

Figure 7. THD vs. RLOAD

Figure 10. Treble responsey

Figure 8. Channel separation vs. frequency

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