TK15220 Audio Analog Switch FEATURES APPLICATIONS ■ ■ ■ ■ ■ ■ Audio Systems ■ Radio Cassettes Wide Operating Voltage Range (2 to 13 V) Low Distortion (typ. 0.004%) Wide Dynamic Range (typ. 6 VP-P) Low Output Impedance (typ. 20 Ω) Protection at Output Terminal. DESCRIPTION TK15220 The TK15220M is an Analog Switch IC that was developed for audio frequency applications. The function of the IC is to select one output from two input channels. The channel selection can be controlled by a higher level by the addition of an external resistor. The TK15220M operates from a single power supply with the input bias built-in (VCC/2). Because the distortion is very low, the TK15220M is suitable for various signal switching applications, especially Hi-Fi devices. The TK15220M offers a wide operating voltage range with simple associated circuitry. 20 P The TK15220M is available in the small SOT23L-6 plastic surface mount package. IN A VCC OUT GND IN B KEY BLOCK DIAGRAM VCC VCC + IN A - VCC OUT VCC KEY ORDERING INFORMATION IN B + GND TK15220M Tape/Reel Code TAPE/REEL CODE TL: Tape Left June 1999 TOKO, Inc. Page 1 TK15220 ABSOLUTE MAXIMUM RATINGS Supply Voltage ......................................................... 14 V Operating Voltage Range ................................. 2 to 13 V Power Dissipation (Note 4) ................................ 200 mW Storage Temperature Range ................... -55 to +150 °C Operating Temperature Range ...................-20 to +75 °C CONTROL SECTION Input Voltage .................................... -0.3 V to VCC +0.3 V ANALOG SWITCH SECTION Signal Input Voltage ......................... -0.3 V to VCC +0.3 V Signal Output Current ............................................. 3 mA Maximum Input Frequency .................................. 100 kHz Lead Soldering Temperature (10 s) ...................... 235 °C TK15210M ELECTRICAL CHARACTERISTICS Test conditions: VCC = 8.0 V, TA = 25 °C, unless otherwise specified. SYMBOL ICC PARAMETER TEST CONDITIONS MIN TYP MAX UNITS 2.5 5.0 mA -0.3 +0.6 V 2.0 VCC + 0.3 V Supply Current KEY CONTROL SECTION VIL Input Voltage Low Level VIH Input Voltage High Level IR Input Resistance Note 1 30 kΩ ANALOG SWITCH SECTION THD Total Harmonic Distortion VIN = 1 Vrms, f = 1 kHz NL Residual Noise Note 2 CT Cross Talk VIN = 1 Vrms, f = 10 kHz, Note 3 DYN Maximum Input Signal Level f = 1 kHz, THD = 0.1% GVA Voltage Gain f = ~20 kHz Vcent Input-Output Terminal Voltage VCC / 2 output ∆Vcent Output Terminal Voltage Difference Between same channel ZIN Input Impedance DC Impedance 36 kΩ ZOUT Output Impedance DC Impedance 20 Ω Note 1: The KEY input equivalent circuit is shown to the right. When the control pin is open, the input is pulled down to a low level. This applies the channel A input signal to the output. A high level changes the output to the channel B input signal. 0.004 -80 0.008 % 10 µVrms -75 dB 2.0 Vrms 0 3.8 Key Input dB 4.0 4.2 V 18 mV Logic Note 2: This value measured with a capacitor connected between the input terminal and ground. See Figure 7. Note 3: This value measured with a 5 kΩ resistor and series capacitor connected between the input terminal and ground. See Figure 8. Note 4: Power dissipation is 200 mW when mounted as recommended. Derate at 1.6 mW/°C for operation above 25°C. Page 2 June 1999 TOKO, Inc. TK15220 TEST CIRCUITS AND METHODS VCC SW6 10 µF + + SW3 SW7 + 10 µF SW4 SW8 SW9 SW2 1 kHz 1 Vrms or 2 Vrms ~ 10 kHz 1 Vrms SW1 SW5 5 kΩ ~ V ~ V _ THD 1: The above condition tests the dynamic range measurement for channel A. 2: SW5 is for residual noise measurement. 3: SW8 is for cross talk measurement. SUPPLY CURRENT (FIGURE 1) VCC + This current is a consumption current with a nonloading condition. 1) Measure the inflow current to Pin 6 from VCC. This current is the supply current. + ~ V OSC VCC A Figure 2 KEY INPUT IMPEDANCE (FIGURE 3) Figure 1 CONTROL LOW/HIGH LEVEL (FIGURE 2) This level is to measure the threshold level. 1) Input the VCC to Pin 6. (This condition is the same with the other measurements, omitted from the next for simplicity.) 2) Input to Pin 1 with a sine wave (1 kHz, 1 Vrms). 3) Connect an oscilloscope to Pin 2. 4) Elevate the Pin 4 voltage from 0 V gradually, until the sine wave appears at the oscilloscope. This voltage is the threshold level when the wave appears. June 1999 TOKO, Inc. This impedance means the base resistance of the input transistor (see terminal circuit on page 8). 1) Remove VCC of Pin 6. 2) Measure the resistance value by measuring instrument. (e.g., multimeter etc.) Figure 3 Page 3 TK15220 TEST CIRCUITS AND METHODS (CONT.) TOTAL HARMONIC DISTORTION (FIGURE 4) Use the lower distortion oscillator for this measurement because the distortion of the TK15220 is very low. 1) Pin 4 is in the open condition, or high level. 2) Connect a distortion analyzer to Pin 2. 3) Input the sine wave (1 kHz, 1 Vrms) to Pin 1. 4) Measure the distortion of Pin 2. This value is the distortion of Ach. 5) Next connect Pin 4 to the VCC, or high level. 6) Input the same sine wave to Pin 3. 7) Measure in the same way. This value is the distortion of Bch. VCC + + ~ V ~ V ~ V1 V2 Figure 5 VCC + + ~ THD Figure 4 VOLTAGE GAIN (FIGURE 5) This is the output level against the input level. 1) Pin 4 is in the open condition, or low level. 2) Connect AC volt meters to Pin 1 and Pin 3. (Using the same type meter is best) 3) Input a sine wave (1 kHz) to Pin 1 (f = optional up to max. 20 kHz, 1 Vrms). 4) Measure the level of Pin 1 and name this V1. 5) Measure the level of Pin 2 and name this V2. 6) Calculate Gain = 20 Log (( |V2 - V1| )/V1) V1<V2 = + Gain, V1>V2 = - Gain This value is the voltage gain of Ach. 7) Next, connect Pin 4 to the GND, or high level. 8) Input the same sine wave to Pin 3. 9) Measure and calculate in the same way. This value is the voltage gain of Bch. Page 4 MAXIMUM INPUT LEVEL (FIGURE 6) This measurement measures at the output side. 1) Pin 4 is in the open condition, or low level. 2) Connect a distortion analyzer and an AC volt meter to Pin 2. 3) Input a sine wave (1 kHz) to Pin 1 and elevate the voltage from 0 V gradually until the distortion gets to 0.1% at Pin 2. 4) When the distortion amounts to 0.1%, stop elevating and measure the AC level of Pin 2. This value is the maximum input level of Ach. 5) Next, connect Pin 4 to the VCC, or high level. 6) Input the same sine wave to Pin 2. 7) Measure in the same way. This value is the maximum input level of Bch. VCC + + ~ THD V ~ Figure 6 June 1999 TOKO, Inc. TK15220 TEST CIRCUITS AND METHODS (CONT.) RESIDUAL NOISE (FIGURE 7) VCC This value is not a S/N ratio. This is a noise which occurs from the device itself. 1) Pin 4 is in the open condition, or low level. 2) Connect an AC volt meter to Pin 2. 3) Connect a capacitor to GND from Pin 1. 4) Measure the AC voltage of Pin 2. This value is the noise of Ach. If the influence of noise from outside exists, use optional filters. 5) Next, connect Pin 4 to the VCC, or high level. 6) Remove the capacitor of Pin 1 and connect the capacitor to Pin 3. 7) Measure in the same way. This value is the noise level of Bch. VCC + + V ~ + + 5K + V ~ V4 V ~ V3 ~ Figure 8 I/O TERMINAL VOLTAGE (FIGURE 9) This is the DC voltage of the input and output. Because the input and the output are nearly equal, only the output is measured. 1) Pin 4 is in the open condition, or low level. 2) Connect a DC volt meter to Pin 2 and measure. This value is the terminal voltage of Ach. 3) Next, connect Pin 4 to the VCC, or high level. 4) Measure in the same way. This value is the terminal voltage of Bch. VCC Figure 7 + CROSS TALK (FIGURE 8) V This is the cross talk between Ach and Bch. 1) Pin 4 is in the open condition, or low level. 2) Connect AC volt meters to Pin 2 and Pin 3. 3) Connect a capacitor and a resistance in series to GND from Pin 1. 4) Input a sine wave (10 kHz, 1 Vrms) to Pin 3. 5) Measure the level of Pin 3 and name this V3. 6) Measure the level of Pin 2 and name this V4. 7) Calculate: Cross Talk = 20 Log (V4 / V3) This value is the cross talk to Ach from Bch. 8) Next, connect Pin 4 to the VCC, or high level. 9) Change line of Pin 1 and Pin 3. 10) Input the same sine wave to Pin 1. 11) Measure and calculate in the same way. This value is the isolation to Bch from Ach. June 1999 TOKO, Inc. Figure 9 OUTPUT TERMINAL DIFFERENCE This is the DC output voltage difference between Ach and Bch. This is calculated by using values measured at the I/O Terminal Voltage. ∆ Vcent = | (Ach DC output value) - (Bch DC output value) | This value is the voltage difference. Page 5 TK15220 TYPICAL PERFORMANCE CHARACTERISTICS VCC = 8 V, TA = 25 °C, unless otherwise specified. MAXIMUM INPUT LEVEL VS. SUPPLY VOLTAGE 5 5 4 4 LEVEL (Vrms) ICC (mA) SUPPLY CURRENT VS. SUPPLY VOLTAGE 3 2 1 3 2 1 0 0 0 2 4 6 8 10 12 14 0 2 4 6 8 10 12 14 VCC (V) VCC (V) TOTAL HARMONIC DISTORTION vs. FREQUENCY TOTAL HARMONIC DISTORTION vs. LOAD RESISTANCE 0.1 0.1 0.01 -20 °C THD (%) THD (%) f = 1 kHz THD = 0.1 % 0.01 +25 °C +75 °C 0.001 0.1 1 10 100 0.001 0.1 10 100 RL (kΩ) CROSS TALK VS. FREQUENCY KEY THRESHOLD VS. TEMPERATURE 2 -50 -60 1.5 LEVEL (V) CT (dB) 1 f (kHz) -70 -80 1 0.5 -90 -100 0.1 1 10 f (kHz) Page 6 100 0 -40 -20 0 20 40 60 80 TA (°C) June 1999 TOKO, Inc. TK15220 TYPICAL PERFORMANCE CHARACTERISTICS (CONT.) VCC = 8 V, TA = 25 °C, unless otherwise specified. VOLTAGE GAIN VS. TEMPERATURE RESIDUAL NOISE VS. TEMPERATURE 8 6 LEVEL (µVrms) LEVEL (dB) +0.1 0 -0.1 -40 4 2 -20 0 20 TA (°C) June 1999 TOKO, Inc. 40 60 80 0 -40 -20 0 20 40 60 80 TA (°C) Page 7 TK15220 TERMINAL VOLTAGE AND CIRCUIT Condition: VCC = 8 V. PIN NO. ASSIGNMENT DC VOLTAGE 1 3 IN A IN B 4V CIRCUIT/FUNCTION Signal Input Pin 2 OUT 4V Signal Output Pin 4 KEY 0V Key Input Pin Page 8 5 GN D 0V Ground Pin 6 VCC 8V Supply Voltage Pin June 1999 TOKO, Inc. TK15220 APPLICATION INFORMATION KEY INPUT CIRCUIT inA Figure 10 illustates the KEY input equivalent circuit. When the control pin is open, the input is pulled down to a low level. This applies the channel A input signal to the output. A high level changes the output to the channel B input signal. The input impedance is approximately 40 kΩ. If it is desired to raise the key threshold level, an external series resistor can be connected. This resistance will elevate the threshold level. VCC 10 µF + + 10 µF 33 µF out + RL + Key 10 µF inB Figure 12 to Logic ZIN Key in CROSS TALK Figure 10 SWITCHING TIME This time is the signal change response time compared to the control key input signal. Figure 11 illustrates the timimg chart. T = 2 µs typically. Figure 13 is an example of a layout pattern. In the application of the TK15220, the following must be considered. Because of the high impedance at the inputs, the capacitors can act as antennas to each other. If the parts are bigger, and the space between the capacitors is too narrow, then cross talk will increase. Therefore, when designing the printed circuit pattern, separate the input capacitors as far as possible and use as small a part as possible (e.g., surface mount types, etc.). Bch (Ach) Key in SW out 50% t Ach (Bch) Figure 11 APPLICATION Figure 12 illustrates an example of a typical application. The standard application is to use capacitor coupling at the inputs and output of the TK15220M. For characteristics of distortion and dynamic range versus RL, refer to the graphs in the Typical Performance Characteristics. The TK15220M can also be used with direct coupling, but the characteristics will get worse (distortion, etc.). If direct coupling is desired, then it is recommended to use external circuitry that is biased compatible with the TK15220M. Use caution that the external channel is of the low level type. June 1999 TOKO, Inc. Figure 13 Page 9 TK15220 APPLICATION INFORMATION (CONT.) OUTPUT TERMINAL VOLTAGE DIFFERENCE This parameter is the output voltage difference between Ach and Bch, and appears when the channel changes from Ach to Bch, or changes to the reverse. Generally, this is called Switching Noise or Pop Noise. If this value is big and if this noise is amplified by the final amplifier and is outputted by the speakers, then it appears as a Shock Sound. Output terminal voltage difference of the TK15220M is a value that adds the internal bias difference and the off-set voltage difference. The value of the TK15220 is very small; its maximum value is 18 mV. Toko can offer the “Muting IC” if users wish to mute Switching Noise. DIRECT TOUCH The signal input terminals: Internal circuits are operated by constant current circuit, even if VCC or GND is contacted, damage does not occur. The signal output terminal: As for inflow, internal circuits are operated by constant current circuit; even if VCC is contacted, damage does not occur. Outflow is protected by the circuit. Even if the terminal is contacted to GND, damage does not happen. Package damage may occur due to heat. Pay attention to long time contact. Do not supply over the maximum rating. Referenced to GND, do not provide any terminal voltages over VCC +0.3 V or -0.3 V. DC SIGNAL INPUT The output of the TK15220M has a saturation voltage (both VCC and GND sides of approximately 1.0 V); accordingly the use of a DC signal is not recommended (e.g., pulse signal, etc.) Page 10 June 1999 TOKO, Inc. TK15220 NOTES June 1999 TOKO, Inc. Page 11 TK15220 PACKAGE OUTLINE Marking Information SOT23L-6 TK15220M S2 0.6 6 5 4 e1 3.0 1.0 Marking 1 2 3 0.32 e +0.15 - 0.05 0.1 e 0.95 M e 0.95 e 0.95 3.5 0.95 Recommended Mount Pad +0.3 - 0.1 2.2 max 15 1.2 0.4 0.15 0.1 +0.15 - 0.05 0 - 0.1 1.4 max 0.3 (3.4) + 0.3 3.3 Dimensions are shown in millimeters Tolerance: x.x = ± 0.2 mm (unless otherwise specified) Toko America, Inc. Headquarters 1250 Feehanville Drive, Mount Prospect, Illinois 60056 Tel: (847) 297-0070 Fax: (847) 699-7864 TOKO AMERICA REGIONAL OFFICES Midwest Regional Office Toko America, Inc. 1250 Feehanville Drive Mount Prospect, IL 60056 Tel: (847) 297-0070 Fax: (847) 699-7864 Western Regional Office Toko America, Inc. 2480 North First Street , Suite 260 San Jose, CA 95131 Tel: (408) 432-8281 Fax: (408) 943-9790 Eastern Regional Office Toko America, Inc. 107 Mill Plain Road Danbury, CT 06811 Tel: (203) 748-6871 Fax: (203) 797-1223 Semiconductor Technical Support Toko Design Center 4755 Forge Road Colorado Springs, CO 80907 Tel: (719) 528-2200 Fax: (719) 528-2375 Visit our Internet site at http://www.tokoam.com The information furnished by TOKO, Inc. is believed to be accurate and reliable. However, TOKO reserves the right to make changes or improvements in the design, specification or manufacture of its products without further notice. TOKO does not assume any liability arising from the application or use of any product or circuit described herein, nor for any infringements of patents or other rights of third parties which may result from the use of its products. No license is granted by implication or otherwise under any patent or patent rights of TOKO, Inc. Page 12 © 1999 Toko, Inc. All Rights Reserved June 1999 TOKO, Inc. IC-119-TK119xx 0798O0.0K Printed in the USA