SSM2018 Analog Devices, SSM2018 Datasheet
SSM2018
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SSM2018 Summary of contents
Page 1
... Voltage (SSM2018T) and differential current (SSM2118T) output versions are of- fered, both laser-trimmed for gain core symmetry and offset result, the SSM2018T is the first professional audio quality VCA to offer trimless operation. The SSM2118T is ideal for low noise summing in large VCA based systems. ...
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... Total Harmonic Distortion plus Noise INPUT AMPLIFIER Bias Current Offset Voltage Offset Current Input Impedance Common-Mode Range Gain Bandwidth Slew Rate OUTPUT AMPLIFIER (SSM2018T) Offset Voltage Output Voltage Swing Minimum Load Resistance CONTROL PORT Bias Current Input Impedance Gain Constant Gain Constant Temperature Coefficient ...
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... C C/W JC TRANSISTOR COUNT Number of Transistors SSM2018T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 SSM2118T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 ESD RATINGS 883 (Human Body) Model . . . . . . . . . . . . . . . . . . . . . . . 500 V EIAJ Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 V 1 Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device ...
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... Figure 2. SSM2018T Distortion Distribution + 18k 15V S 0.1 0.010 0.001 1 0.1 AMPLITUDE – V Figure 3. SSM2018T THD + N vs. Amplitude (Gain = 0 dB kHz, 80 kHz Low-Pass Filter +20dB 0.010 0.001 10k 20k Figure 4. SSM2018T THD + N vs. Amplitude (Gain = +20 dB +20 dB, V 1.0 0.1 0.01 0.001 ...
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... Figure 10. SSM2018T Maximum Output Swing vs. Load Resistance, (THD = 1 % max) 100 10k –80 Figure 11. SSM2018T Output Offset vs. Gain + –5 –10 –15 100k 100 Figure 12. SSM2018T Gain/Phase vs. Frequency –5– SSM2018T/SSM2118T R = 18k + ...
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... SSM2018T/SSM2118T–Typical Characteristics –20 –40 –60 –80 100 1k 10k 100k FREQUENCY – Hz Figure 13. SSM2018T Gain vs. Frequency 0 + 18k +20dB V 0.010 A = 0dB V 0.001 20 100 1k FREQUENCY – Hz Figure 14. SSM2118T THD + N Frequency (80 kHz Low-Pass Filter, for dB ...
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... Figure 23. SSM2118T Output Offset Current vs. Gain + –5 –10 –15 20 100 Figure 24. SSM2118T Gain/Phase vs. Frequency –7– SSM2018T/SSM2118T 15V S 10k FREQUENCY – + 15V S –60 –40 – GAIN – +25 C ...
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... TEMPERATURE – C Figure 26. SSM2018T and SSM2118T Distortion vs. Temperature – + 15V S –70 –80 –90 –100 –110 –60 –40 –20 0 GAIN – dB Figure 27. SSM2018T and SSM2118T Output Noise vs. Gain (V = GND, 20 kHz Bandwidth) IN 100 1.5V S OP275 AS 80 I/V CONV ...
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... V = 15V S –25 –30 –35 –40 –40 – TEMPERATURE – C Figure 31. SSM2018T and SSM2118T Gain Constant vs. Temperature – + 15V S –29 –30 –31 –32 –33 –80 –60 –40 –20 0 GAIN – dB Figure 32. SSM2018T and SSM2118T Gain Constant Linearity vs. Gain ...
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... VCA configuration with class AB biasing. Thus, for optimal distortion and control feedthrough perfor- mance, the same configuration and biasing should be used. All of the graphs for the SSM2018T in the data sheet have been measured using the circuit of Figure 37. 50pF ...
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... A2 struction as the SSM2018T. Thus, any discussion of these por- V OUT * 50pF tions of the SSM2018T apply equally to the SSM2118T. The 10k 18k main difference, which is apparent by comparing Figure 40 to Figure 38, is the removal of two output amplifiers, A1 and A3. 10k Instead, the output currents come directly from the collectors of ...
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... The control voltage not only adjusts the gain core steering, it also adjusts the com- pensation. The SSM2018T and SSM2118T have three com- pensation pins: COMP1, COMP2, and COMP3. COMP3 is normally left open. Grounding this pin actually defeats the adaptive compensation circuitry, giving the VCA a fixed com- pensation point ...
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... R : 150k FOR CLASS CONNECT B Figure 41. Upgrading SSM2018 Sockets If the SSM2018 is used in the OVCE or VCP configuration, the such that B SSM2018T can still directly replace it. However, the potenti- ometers cannot necessarily be removed, as explained in the OVCE and VCP sections. Temperature Compensation of the Gain Constant As explained above, the gain constant has a 3500 ppm/ C tem- perature drift due to the inherent nature of the control port ...
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... AD797 should be used to ensure a very low impedance ground over the full audio frequency range. The minimum op- erating supply for the SSM2018 which gives a mini- mum single supply of +10 V and ground. The performance of the circuit with + identical to graphs that show operation of the SSM2018T with 5 V supplies. – ...
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... Figure 47. Notice that the amplifier whose output (Pin 16) was originally connected now the output for feed- MINUS back. As mentioned before, because the SSM2018T is trimmed for the basic VCA configuration, potentiometers are needed for the OVCE configuration to ensure the best THD and control feedthrough performance. ...
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... SSM2018T/SSM2118T Voltage Controlled Panner An interesting circuit that is built with the OVCE building block is a voltage controlled panner. Figure 48 shows the feedback connection for the circuit. Notice that the average of both out- puts is fed back to the input. Thus, the average must be equal to the input voltage ...