PCM78 Burr-Brown Corporation, PCM78 Datasheet
PCM78
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PCM78 Summary of contents
Page 1
... It features very fast, low distortion performance (4 s/–88dB THD+N typical) and is complete with internal clock and reference circuitry. The PCM78P is packaged in a reliable, low- cost 28-pin plastic DIP and data output is available in user-selectable serial output formats. The PCM78P is ideal for digital audio tape (DAT) recorders. Many ...
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... FSR 0.003 % of FSR (8) None 14 Bits 25 ppm ppm of FSR/ C 0.008 %FSR/%V CC 0.003 %FSR/%V CC 0.003 %FSR/%V DD +15.6 V –15.6 V +5.25 V +15 mA – 575 mW +70 C +100 C + sample frequency (PCM78P and SHC702 in S ...
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... Logic Inputs to Digital Common ................................. –0. 8000 Hex Analog Inputs to Analog Common .................................................. 16.5V 7FFF Hex Lead Temperature (soldering, 10s) ................................................ +300 C Stresses above these ratings may permanently damage the device. PACKAGE DRAWING (1) NUMBER 215 3 clock to initiate latch and an internal convert OUT2 + 0.5V DD PCM78 ® ...
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... DD –0.008 –0.010 – Temperature (° TEMP REF 2.002 2.000 1.998 1.996 1.994 1.992 1.99 1.988 – Temperature (°C) ® PCM78 –0.35 70 125 0.012 0.01 0.008 0.006 0.004 0.002 0 70 125 –25 ...
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... Major Carry Bit Number DIFFERENTIAL NONLINEARITY at 0°C 1.40 1.20 1.00 0.80 0.60 0.40 0.20 0. Major Carry Bit Number DIFFERENTIAL NONLINEARITY at 25°C 1.40 1.20 1.00 0.80 0.60 0.40 0.20 0. Major Carry Bit Number PCM78 ® ...
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... Major Carry Bit Number INTEGRAL NONLINEARITY ERROR (to 14-Bit LSB) 1.50 1.00 0.50 0.00 –0.50 –1.00 –1.50 –2.00 –8192 –4096 0.000 BIN ® PCM78 (CONT) 1.80 1.60 1.40 1.20 1.00 0.80 0.60 0.40 0.20 0. 2.50 2.00 1.50 1.00 0.50 0. 2.00 1.50 1.00 0.50 0.00 –0.50 –1.00 4096 8192 –8192 ...
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... SINAD: 61.28dB 5th: –97.57dB 100 Frequency (kHz) SPECTRAL RESPONSE, f 20kHz IN Input Frequency 19970.7Hz Fund: –59.96dB 6th: –110.11dB 2nd: –109.09dB THD: –41.60dB 3rd: –124.49dB SNR: 21.93dB 4th: –116.40dB SINAD: 21.88dB 5th: –112.18dB 100 Frequency (kHz) PCM78 ® ...
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... Convert Time (µs) ® PCM78 THEORY OF OPERATION (CONT) The PCM78P is a successive approximation A/D converter; this type of converter is well suited to high speed and resolution. The accuracy of a successive approximation converter is described by the transfer function shown in Figure 1. All successive-approximation A/ D converters have an inherent quantization error of ...
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... Timing Digital Distortion Analyzer Software DataPhysics Corp THD+N of the PCM78 is shown in Figure 2. This digital system is capable of differentiating harmonic energy and noise; conventional distortion analyzers which operate on a tracking notch filter principle cannot distinguish this energy, and therefore only measure THD+N. Unfortunately, in the ...
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... THD+N and the square root of the sum of the squares of the linearity errors at each digital word of interest. In order to find this error at each code, a histogram test must be performed on the PCM78, as illustrated in Figure 3. The histogram for every converter is unique, as the linearity errors from converter to converter will vary in their place- ment along the transfer function ...
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... NOTE: (1) When using the internal clock, the clock does not operate until the Convert Command is low therefore possible to keep the convert command high indefinitely, thereby keeping the PCM78 in a halt mode. The conversion cycle begins on the falling edge of convert command, and convert command must remain low during the entire conversion cycle in order to make the PCM78 operate properly ...
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... Delay from rising edge of 17th clock pulse to falling edge of STATUS 9 NOTE: (1) The PCM78 does not contain dynamic digital circuitry, and can be clocked as slowly as the user wishes. In typical applications, the longest clock period may be as long FIGURE 7. Conversion Timing when using External Clock. ...
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... MSB LSB JUMPER NO OF BITS (PCM78 Short Cycle Off PCM78 ® ...
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... The analog input should be scaled as close to the maximum input signal range as possible in order to utilize the maximum signal resolution of the A/ D converter. The DAC inside the PCM78 has a 2mA range, and the nominal 3V input is scaled by a 1.5k resistor. In order to scale to other ranges, see Table I for recommended scaling resistor values, connected as shown in Figure 14 ...
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... FIGURE 16. MSB Adjust Circuit. APPLICATIONS INFORMATION A typical digitization circuit, used on the demonstration board available for the PCM78, is shown in Figure 20. The connections and part values shown in this circuit have been optimized for the best THD+N performance at a 200kHz sample rate. The PCM78 may be interfaced to many popular digital signal processors, such as the TMS320, DSP56001, and the DSP32 ...
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... ® PCM78 GND B10 B11 B12 B13 B14 B15 B16 DV –5 GND +5 +15 GND –15 Clock External INT 3. ...