TDA7448 6 CHANNEL VOLUME CONTROLLER 1 ■ ■ ■ ■ ■ ■ 2 Figure 1. Package FEATURES 6 CHANNEL INPUTS 6 CHANNEL OUTPUTS VOLUME ATTENUATION RANGE OF 0 TO -79dB VOLUME CONTROL IN 1.0dB STEPS 6 CHANNEL INDEPENDENT CONTROL SO-20 Table 1.
TDA7448 Table 2. Absolute Maximum Ratings Symbol VS Parameter Value Unit 10.5 V 0 to 70 °C -55 to 150 °C Value Unit 150 °C/W Operating Supply Voltage Tamb Operating Ambient Temperature Tstg Storage Temperature Range Figure 3. Pin Connection (Top view) VS 1 20 CREF IN1 2 19 IN2 IN3 3 18 IN4 IN5 4 17 IN6 OUT5 5 16 OUT6 OUT3 6 15 OUT4 OUT1 7 14 OUT2 N.C. 8 13 N.C. SDA 9 12 ADDR SCL 10 11 GND D02AU1397 Table 3.
TDA7448 Table 5. Electrical Characteristcs (refer to the test circuit Tamb = 25°C, VS = 9V, RL = 10KΩ, RG = 600Ω, unless otherwise specified) Symbol Parameter Test Condition Min. Typ. Max. Unit 4.75 9 10 V SUPPLY VS Supply Voltage IS Supply Current 7 mA Ripple Rejection 80 dB SVR INPUT STAGE RIN Input Resistance 35 50 VCL Clipping Level THD = 0.3% SIN Input Separation The selected input is grounded through a 2.2µ capacitor 65 KΩ 2 2.
TDA7448 Figure 4. Test circuit 0.47µF IN1 IN1 7 2 VOLUME OUT1 50K 0.47µF IN2 IN2 14 19 VOLUME OUT2 50K 0.47µF IN3 IN3 6 3 VOLUME OUT3 50K 0.47µF IN4 IN4 15 18 VOLUME OUT4 50K 0.47µF IN5 IN5 5 4 VOLUME OUT5 50K 0.47µF IN6 IN6 16 17 VOLUME OUT6 50K GND CREF 11 APPLICATION SUGGESTIONS 10 9 11 20 10µF 3 I2C BUS DECODER SUPPLY 1 VS SCL SDA ADDR D02AU1406 Figure 6. THD vs. RLOAD The volume control range is 0 to -79dB, by 1dB step resolution.
TDA7448 4 I2C BUS INTERFACE Data transmission from microprocessor to the TDA7448 and vice versa takes place through the 2 wires I2C BUS interface, consisting of the two lines SDA and SCL (pull-up resistors to positive supply voltage must be connected). 4.1 Data Validity As shown in fig. 8, 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. 4.
TDA7448 5 SOFTWARE SPECIFICATION Interface 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)) CHIP ADDRESS SUBADDRESS MSB S 1 LSB 0 0 0 1 0 0 0 MSB ACK X DATA 1 to DATA n LSB X X B DATA MSB ACK LSB DATA ACK P D96AU420 ACK = Acknowledge; S = Start; P = Stop; A = Address; B = Auto Increment 5.1 EXAMPLES 5.1.
TDA7448 In 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: Table 7. SUBADDRESS XXX10010 SPEAKER ATTENUATION OUT 1 XXXXXXXX SPEAKER ATTENUATION OUT 2 XXXXXXXX SPEAKER ATTENUATION OUT 3 00000000 SPEAKER ATTENUATION OUT 4 XXXXXXXX SPEAKER ATTENUATION OUT 5 XXXXXXXX SPEAKER ATTENUATION OUT 6 00101111 Table 8.
TDA7448 Figure 14. PINS: 10 Figure 11. PIN:20 VS VS 20µA 20K SCL CREF 20K D96AU424 D96AU430 Figure 12. PINS: 5, 6, 7, 14, 15, 16 Figure 15. PINS: 9 VS 20µA 24 OUT1 to OUT6 SDA 20µA D96AU423 D02AU1398 Figure 13.
TDA7448 Figure 16. Test and Application Circuit J1 J2 OUT1 IN1 J3 IC1 GND 7 OUT6 C10 5 0.47µF C12 17 C13 IN6 15 0.47µF 4 C11 + 6 OUT5 + IN6 IN5 C8 18 C9 + 5 OUT4 0.47µF 16 OUT1 2 OUT2 3 OUT3 4 OUT4 5 OUT5 6 OUT6 7 GND 22µF 16V 22µF 16V + IN5 C7 IN4 C6 6 1 22µF 16V 22µF 16V + 4 OUT3 14 0.47µF 3 22µF 16V 22µF 16V + IN4 IN3 C4 19 C5 OUT2 0.47µF 10µF 16V 20 8 13 CREF SCL N.C. SDA N.C.
TDA7448 Figure 17. Component Layout (65 x 72mm) Figure 18.
TDA7448 Figure 19.
TDA7448 Figure 20. SO-20 Mechanical Data & Package Dimensions mm inch DIM. MIN. TYP. MAX. MIN. TYP. MAX. A 2.35 2.65 0.093 0.104 A1 0.10 0.30 0.004 0.012 B 0.33 0.51 0.013 0.200 C 0.23 0.32 0.009 0.013 D (1) 12.60 13.00 0.496 0.512 E 7.40 7.60 0.291 0.299 e 1.27 0.050 H 10.0 10.65 0.394 0.419 h 0.25 0.75 0.010 0.030 L 0.40 1.27 0.016 0.050 k ddd OUTLINE AND MECHANICAL DATA 0˚ (min.), 8˚ (max.) 0.10 0.
TDA7448 Table 9. Revision History Date Revision Description of Changes January 2004 1 First Issue June 2004 3 Modified the style-sheet in compliance with the last revision of the “Corporate Technical Pubblications Design Guide”.
TDA7448 Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice.
