2181-DEMO THAT Corporation, 2181-DEMO Datasheet
2181-DEMO
Specifications of 2181-DEMO
Related parts for 2181-DEMO
2181-DEMO Summary of contents
Page 1
... BIAS CURRENT COMPENSATION Input 1 6 Gnd Figure 1. 2181 Series Equivalent Circuit Diagram THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com Copyright © 2008, THAT Corporation Blackmer Voltage Controlled Amplifiers THAT 2181A, 2181B, 2181C APPLICATIONS • ...
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... 20kΩ out 0 dB gain — -98 -97 +15 dB gain — -88 -86 No Signal -3.1 -2.85 -2.6 -3.1 -2.85 Copyright © 2008, THAT Corporation THAT 2181 Series Blackmer® Trimmable IC VCAs 2 ºC) 330 +70 º -40 to +125 ºC ST 2181B 2181C Typ Max ...
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... GND Rsym 5.1k 680k (2181A) 220k (2181B) 130k (2181C) Vee Figure 2. Typical Application Circuit Figure 4. 2181 Series Noise (20kHz NBW) vs. Gain Copyright © 2008, THAT Corporation Document 600030 Rev 02 2 2181B 2181C Typ Max Min Typ Max Units — 0.005 0.02 % — ...
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... Figure 5. Simplified Internal Circuit Diagram 4. For more details about the internal workings of the 2181 Series of VCAs, see An Improved Monolithic Voltage-Controlled Amplifier, by Gary K. Hebert (Chief Technology Officer, for THAT Corporation), presented at the 99th convention of the Audio Engineering Society, New York, Preprint number 4055. ...
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... Because of the exponential characteristic, the control voltage sets gain linearly in decibels. Figure 6 shows the decibel current gain of a 2181 versus the voltage at Ec+, while Figure 7 shows gain versus the Ec-. Temperature Effects The logging and antilogging in the VCA depends ...
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... Figure 12. 1 kHz THD+Noise vs. Input Level, -15dB Gain THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com Page Figure 13. 2181A THD+N vs Frequency, 0dB gain 1kHz 1V Figure 14. FFT of THD, Typical 2181A, Copyright © 2008, THAT Corporation THAT 2181 Series Blackmer® ...
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... Refer to Figures 10 through 12 to see how distor- tion varies with signal level for the three parts in the 2181 Series for 0 dB, +15 dB and -15 dB gain. The circuit of Figure 2, Page 3 was used to generate these curves. For a specific application, the acceptable distor- tion will usually determine the maximum signal current level which may be used ...
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... R /R for an inverting opamp will f i determine the overall voltage gain when the 2181 is set for 0 dB current gain. Since the VCA performs best at settings near unity gain, use the input and feedback resistors to provide design-center gain or loss, if necessary. ...
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... The 2181 Series VCAs are designed to be operated with zero source impedance at pins 2 and 3, and a high (≥50 kΩ) source impedance at pin 4. To realize all the performance designed into a 2181, keep the source impedance of the control voltage driver well under 50 Ω. This often suggests driving the control port directly with an opamp ...
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... Document 600030 Rev 02 The 2181 Series VCAs have a small amount of inherent noise modulation because of its class AB biasing scheme, where the shot noise in the core transistors reaches a minimum with no signal, and increases with the square root of the instantaneous signal current. However optimum circuit, the noise floor rises only to -94 dBV with a 50 μ ...
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... THAT 2181 Series Blackmer® Trimmable IC VCAs The THAT 2181-series is available in 8-pin SO and 8-pin SIP packages. Package dimensions are shown in Figure 16 and 17 below; Pinouts are given in Table 1 on page 1. Ordering information is provided in Table 2 also on page 1. The 2181-series packages are entirely lead-free. ...
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... Document 600030 Rev 02 THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com Page Notes Copyright © 2008, THAT Corporation THAT 2181 Series Blackmer® Trimmable IC VCAs ...