TDA7448 ,6 CHANNELS VOLUME CONTROLLERTDA74486 CHANNEL VOLUME CONTROLLERPRODUCT PREVIEW■ 6 CHANNEL INPUTS■ 6 CHANNEL OUTPUTS■ VOLUME ATTE ..
TDA7448. ,6 CHANNELS VOLUME CONTROLLERTDA74486 CHANNEL VOLUME CONTROLLERPRODUCT PREVIEW■ 6 CHANNEL INPUTS■ 6 CHANNEL OUTPUTS■ VOLUME ATTE ..
TDA744813TR ,6 CHANNELS VOLUME CONTROLLERapplications in Multi-Channels AudioLow Distortion, Low Noise and DC stepping are ob-Systemstained. ..
TDA744813TR ,6 CHANNELS VOLUME CONTROLLERBlock Diagram72IN1 OUT1VOLUME50K1419IN2 OUT2VOLUME50K63IN3 OUT3VOLUME50K1518IN4 OUT4VOLUME50K54IN5 ..
TDA744813TR ,6 CHANNELS VOLUME CONTROLLERFEATURES■ 6 CHANNEL INPUTS■ 6 CHANNEL OUTPUTS■ VOLUME ATTENUATION RANGE OFSO-200 TO -79dB■ VOLUME C ..
TDA7449 ,TONE CONTROL DIGITALLY CONTROLLED AUDIO PROCESSORTDA7449®TONE CONTROLDIGITALLY CONTROLLED AUDIO PROCESSORINPUT MULTIPLEXER- 2 STEREO INPUTS- SELECTA ..
THS1030CPW ,10-Bit, 30 MSPS ADC Single Ch., Pin Comp. w/TLC876, Out of Range Indicator, PowerDownmaximum ratings” may cause permanent damage to the device. These are stress ratings only, andfuncti ..
THS1030CPWRG4 ,10-Bit, 30 MSPS ADC Single Ch., Pin Comp. w/TLC876, Out of Range Indicator, PowerDown 28-TSSOP 0 to 70maximum ratings” may cause permanent damage to the device. These are stress ratings only, andfuncti ..
THS1030IDW ,10-Bit, 30 MSPS ADC Single Ch., Pin Comp. w/TLC876, Out of Range Indicator, PowerDownmaximum ratings over operating free-air temperature (unless otherwise noted)Supply voltage range: A ..
THS1030IPW ,10-Bit, 30 MSPS ADC Single Ch., Pin Comp. w/TLC876, Out of Range Indicator, PowerDown SLAS243E − NOVEMBER 1999 − REVISED ..
THS1030IPWR ,10-Bit, 30 MSPS ADC Single Ch., Pin Comp. w/TLC876, Out of Range Indicator, PowerDownblock diagramCore10AIN SampleOutputI/O(0−9)and ADCREFTSBufferHoldREFBSOVRInternal OEAReferenceB Buf ..
THS1031IPW ,10-Bit, 30 MSPS ADC Single Ch., Integ. Pgmable Digital Clamp & Gain, Out of Range Indic., PowerDownTHS1031 3-V TO 5.5-V, 10-BIT, 30 MSPSCMOS ANALOG-TO-DIGITAL CONVERTERSLAS242E – NOVEMBER 1999 – REV ..
TDA7448-TDA7448.
6 CHANNELS VOLUME CONTROLLER
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TDA7448December 2002 6 CHANNEL INPUTS 6 CHANNEL OUTPUTS VOLUME ATTENUATION RANGE OF
0 TO -79dB VOLUME CONTROL IN 1.0dB STEPS 6 CHANNEL INDEPENDENT CONTROL ALL FUNCTION ARE PROGRAMMABLE VIA
SERIAL BUS
DESCRIPTIOThe TDA7448 is a 6 channel volume controller for
quality audio applications in Multi-Channels Audio
Systems
Thanks to the used BIPOLAR/CMOS Technology,
Low Distortion, Low Noise and DC stepping are ob-
tained.
PRODUCT PREVIEW6 CHANNEL VOLUME CONTROLLER
BLOCK DIAGRAM
TDA7448 2/13
ABSOLUTE MAXIMUM RATINGS
PIN CONNECTION
THERMAL DATA
QUICK REFERENCE DATA
3/13
TDA7448
ELECTRICAL CHARACTERISTCS (refer to the test circuit Tamb = 25°C, VS = 9V, RL = 10KΩ, RG = 600Ω, unless otherwise specified)
TDA7448 4/13
Figure 1. Test circuit
APPLICATION SUGGESTIONSThe volume control range is 0 to -79dB, by 1dB step
resolution.
The very high resolution allows the implementation of
systems free from any noise acoustical effect.
CREFThe suggested 10μF reference capacitor (CREF)
value can be reduced to 4.7μF if the application re-
quires faster power ON.
Figure 2. THD vs. frequency
Figure 3. THD vs. RLOAD
Figure 4. Channel separation vs. frequency
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TDA74482 C BUS INTERFACEData transmission from microprocessor to the TDA7448 and vice versa takes place through the 2 wires I2 C BUS in-
terface, consisting of the two lines SDA and SCL (pull-up resistors to positive supply voltage must be connected).
Data ValidityAs shown in fig. 1, the data on the SDA line must be stable during the high period of the clock. The HIGH and
LOW state of the data line can only change when the clock signal on the SCL line is LOW.
Start and Stop ConditionsAs shown in fig. 2 a start condition is a HIGH to LOW transition of the SDA line while SCL is HIGH. The stop
condition is a LOW to HIGH transition of the SDA line while SCL is HIGH.
Byte FormatEvery byte transferred on the SDA line must contain 8 bits. Each byte must be followed by an acknowledge bit.
The MSB is transferred first.
AcknowledgeThe master (μP) puts a resistive HIGH level on the SDA line during the acknowledge clock pulse (see fig. 5). The
peripheral (audio processor) that acknowledges has to pull-down (LOW) the SDA line during this clock pulse.
The audio processor which has been addressed has to generate an acknowledge after the reception of each
byte, otherwise the SDA line remains at the HIGH level during the ninth clock pulse time. In this case the master
transmitter can generate the STOP information in order to abort the transfer.
Transmission without AcknowledgeAvoiding to detect the acknowledge of the audio processor, the μP can use a simpler transmission: simply it
waits one clock without checking the slave acknowledging, and sends the new data.
This approach of course is less protected from misworking.
Figure 5. Data Validity on the I2 CBUS
Figure 6. Timing Diagram of I2 CBUS
Figure 7. Acknowledge on the I2 CBUS
TDA7448 6/13
SOFTWARE SPECIFICATIONInterface Protocol
The interface protocol comprises: A start condition (S) A chip address byte, containing the TDA7448 address A subaddress bytes A sequence of data (N byte + acknowledge) A stop condition (P))
ACK = Acknowledge; S = Start; P = Stop; A = Address; B = Auto Increment
EXAMPLES
No Incremental BusThe TDA7448 receives a start condition, the correct chip address, a subaddress with the B = 0 (no incremental
bus), N-data (all these data concern the subaddress selected), a stop condition.
Incremental BusThe TDA7448 receivea start conditions, the correct chip address, a subaddress with the B = 1 (incremental bus):
now it is in a loop condition with an autoincrease of the subaddress whereas SUBADDRESS from "XXX1000"
to "XXX1111" of DATA are ignored.The DATA 1 concern the subaddress sent, and the DATA 2 concern the
subaddress sent plus one in the loop etc, and at the end it receivers the stop condition.
DATA BYTESAddress= 88 (HEX) (10001000): ADDR open; 8A (HEX) (10001010): connect to supply
FUNCTION SELECTION: subaddress
B=1: INCREMENTAL BUS; ACTIVE
B=0: NO INCREMENTAL BUS
X= DON’T CARE
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TDA7448In Incremental Bus Mode, the three “not used” functions must be addressed in any case. For example to refresh
“ Speaker Attenuation 3 = 0dB and Speaker Attenuation 6 = -40 dB”; the following bytes must be sent:
SPEAKER ATTENUATION SELECTIONvalue = 0 to -79dB and MUTE
