SM7153

三合微科股份有限公司 SM7153 SAMHOP Microelectronics Corp. ELECTRONIC VOLUME CONTROLLER FEATURES * 0dB to -66dB attenuation controlled by 2dB/step * 2 channels built in * High voltage CMOS technology operating voltage range: VCC=6 ~ 12V PIN ASSIGNMENT Vss L-OUT1 L-IN1 A-GND L-IN2 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 VDD R-OUT1 R-IN1 A-GND R-IN2 R-OUT2 U/D OSC SM7153 APPLICATION Audio Equipment Volume Control. L-OUT2 INH DCO BLOCK DIAGRAM VDD 16 VSS 1 INH 7 U/D 10 U/D 7 BITS CK BI-DIRECTIONAL SHIFT REGISTER INT U/D 6 BITS CK BI-DIRECTIONAL SHIFT REGISTER AUTO INITIALISE CIRCUIT INT OSC 9 OSC CONSTANT CURRENT CIRCUIT VDD 8 DCO L-OUT1 L-IN1 2 3 A-SW A-SW CK CK A-SW A-SW 15 14 R-OUT1 R-IN1 7bit LATCH CIRCUIT A-SW A-SW A-SW A-SW A-SW A-GND 4 L-IN2 5 A-SW A-SW A-SW A-SW A-SW A-SW L-OUT2 6 7bit LATCH CIRCUIT A-SW A-SW A-SW A-SW CK CK A-SW 13 A-GND R-IN2 CK 6bit LATCH CIRCUIT CK 6bit LATCH CIRCUIT A-SW A-SW A-SW A-SW A-SW A-SW 12 11 R-OUT2 Page 1 V.1.0 三合微科股份有限公司 SM7153 SAMHOP Microelectronics Corp. ELECTRONIC VOLUME CONTROLLER PIN DESCRIPTION Pin 2 15 3 14 4 13 5 12 6 11 7 Symbol L-OUT1 R-OUT1 L-IN1 R-IN1 A-GND L-IN2 R-IN2 L-OUT2 R-OUT2 INH Description 10dB/step attenuator outputs. A signal applied to IN is attenuated in 7 steps from 0dB to 60dB at 10dB/step. 10dB/step attenuator inputs Analog ground terminal 2 dB/step attenuator inputs 2 dB/step attenuator inputs A signal applied to IN is attenuated in 5 steps from 0dB to 8dB at 2 dB/step. Inhibit terminal. When this terminal is at ' L ' level, all input/ output cut off and the SM7153 is placed in the inhibit state. When at ' H ' level, the SM7153 operates normally. DC current output for displaying attenuation. C, R connecting terminal for the oscillator. up/down speed of attenuation is decided by the attenuation up/down control oscillator according to this time constant. Attenuation up/down control input terminal. When this terminal is at ' H ' level, sound volume is increased synchronising with rise of the oscillator. Conversely, when this pin is at ' L ' level, sound volume is decreased. Negative Power Supply Positive Power Supply (Substrate) Page 2 V.1.0 8 9 DCO OSC 10 U/D 1 16 VSS VDD 三合微科股份有限公司 SM7153 SAMHOP Microelectronics Corp. ELECTRONIC VOLUME CONTROLLER FUNCTION DESCRIPTION (1) Setting Of Attenuation After power on, attenuation is automatically set at -40dB. POWER SUPPLY U/D OSC -30dB -32dB -34dB -36dB -38dB -40dB Figure 1 When the UP key is pressed after power ON, the U/D terminal is placed in the up state at ' H ' level, and the oscillator is actuated. When the DOWN key is pressed, t DOWN key is pressed, and the oscillator is actuated in the down state and therefore, attenuation is decreased. Oscillation frequency is decided by Cx and Rx. 1 0.7 Cx * Rx VDD RS CX OSC fosc≒ (Hz) (Rs≧3Rx) osc RX U/D UP DWOM + RX=33 KΩ - 2.2uF CX=4.7µF RS=100 KΩ VSS Figure 2 Page 3 V.1.0 三合微科股份有限公司 SM7153 SAMHOP Microelectronics Corp. ELECTRONIC VOLUME CONTROLLER (2) Attenuation Display Output The SM7153 is provided with the DC current output terminal for displaying attenuation. With 0dB ~ ∞ divided into 13 steps, current of approx. 100µA/step is transmitted. Step 0 1 2 3 4 5 6 7 8 9 10 11 12 13 DCO 0 I = 100μA + 30μA 2xI 3xI 4xI 5xI 6xI 7xI 8xI 9xI 10 x I 11 x I 12 x I 13 x I Attenuation -64 dB ~ ∞ -60dB ~ -62dB -54dB ~ -58dB -50dB ~ -52dB -44dB ~ -48dB -40dB ~ -42dB -34dB ~ -38dB -30dB ~ -32dB -24dB ~ -28dB -20dB ~ -22dB -14dB ~ -18dB -10dB ~ -12dB -4dB ~ -8dB 0dB ~ -2dB TABLE 1 13 12 8 1KΩ VSS 7 6 5 4 3 2 STEP 0 1 ABOUT 100mV + 30mV Figure 3 When high precision is required, use a variable resistor as a load resistor. VSS 8 ABOUT 1.3V 10 9 11 Page 4 V.1.0 三合微科股份有限公司 SM7153 SAMHOP Microelectronics Corp. ELECTRONIC VOLUME CONTROLLER (3) Attenuator The attenuator unit consist of diffused resistors and analog switches. Attenuator 1 attenuates 0~60dB at 10dB/step while Attenuator 2 attenuates 2~8dB at 2dB/step, a total of 0~66dB at 2dB/step. 0dB IN1 -10 -20 -30 BUFFER AMP IN2 OUT1 0 -2 -4 -6 OUT2 R1 -40 -50 -60 R2 -8 00 ATTENUATOR 2 ATTENUATOR 1 A-GND R1=50kΩ(Typ.) R2=20kΩ(Typ.) Figure 4 If there is the possibility for excessive voltage being to the attenuator, it is recommended to insert a protective diode as illustrated below. VDD VDD IN Vss Vss Figure 5 Page 5 V.1.0 三合微科股份有限公司 SM7153 SAMHOP Microelectronics Corp. ELECTRONIC VOLUME CONTROLLER (4) Power Supply (a) Dual Power Supply ≈ VDD A-GND U/D OSC +VDD OSC U/D ≈ Vss INH DCO OV -Vss VDD DC UP DOWN Figure 6 (b) Single Power Supply ≈ VDD A-GND U/D OSC +VDD 1/2 VDD OV(Vss) ≈ Vss INH DCO VDD Figure 7 Page 6 V.1.0 三合微科股份有限公司 SM7153 SAMHOP Microelectronics Corp. ELECTRONIC VOLUME CONTROLLER (5) Backup When Power Off When the INH terminal is set at ' L ' level, all input/output terminals are shut off and current consumption is reduced to the minimum. The back up by means of a capacitor becomes possible in this condition. An application circuit is shown in Figure 8. +B VDD 10KΩ + - 51KΩ -Vss Figure 8 If VDD-Vss drops below 4V, the backup becomes impossible. (6) Initialisation When Power ON When VDD-VSS drops below 4V, the auto-initialising function is actuated. The initialising level is -40dB. If rise of power supply is to It is recommended to rise supply voltage and the INH terminal as illustrated below. VDD - VSS OR INH TERMINAL VOLTAGE T Figure 9 T≧1 msec SM7153 * VDD - VSS = 4.0V Page 7 V.1.0 三合微科股份有限公司 SM7153 SAMHOP Microelectronics Corp. ELECTRONIC VOLUME CONTROLLER MAXIMUM RATINGS (TA=25oC) Parameter Supply Voltage Input Voltage Power Dissipation Operating Temperature Storage Temperature Symbol VDD VIN PD Topr Tstg Ratings 15 VSS-0.3 ~ VDD+0.3 Unit V V mW ℃ ℃ 150 -20 ~ +75 -40 ~ +125 ELECTRICAL CHARACTERISTICS (Unless otherwise specified, VDD=12V, VSS=0V, Ta=25oC) Parameter Supply Voltage Supply Current Stand-by Current Input Voltage 'H' LEVEL 'L' LEVEL Symbol VDD IDD IB VIH VIL Test Condition Min. 6 - Typ. 1 - Max. 12 3 300 VDD+0.3 VDDx0.2 Unit V mA µA V VDD=4V,INH=L INH, U/D Terminal R-IN1 -A-GND (L-IN1) R-IN2 -A-GND (L-IN2) 0.8VDD VSS-0.3 Attenuator 1 resistor (10dB / step) Attenuator 2 resistor (2dB / step) Attenuation Error Max input Amplitude Max clock Frequency Min clock Width RATT-1 25 50 70 KΩ RATT-2 Vin fck Tck 10 - 20 - 28 2 4.0 100 - KΩ dB Vrms KHz µS Biase 0V 5 Page 8 V.1.0 三合微科股份有限公司 SM7153 SAMHOP Microelectronics Corp. ELECTRONIC VOLUME CONTROLLER APPLICATION CIRCUIT (L-ch Only) -6V Vss 10µF 680KΩ 1µF +6V VDD 10µF 1µF 470K Ω 82K Ω 120KΩ 4 TA75558P +1 -8 2 10µF 3 27pF 1 1µF INPUT GND 1µF OUTPUT 16 15 14 SM7153 13 12 11 10 19 CX 2 3 4 5 6 7 8 10K RS 1N4148 RX 1N4148 UP SW DOWN SW 1µF Page 9 V.1.0