Datasheet LTC1051, LTC1053 (Analog Devices) - 10
| Fabricante | Analog Devices |
| Descripción | Dual/Quad Precision Zero-Drift Operational Amplifiers with Internal Capacitors |
| Páginas / Página | 16 / 10 — APPLICATIO S I FOR ATIO |
| Formato / tamaño de archivo | PDF / 306 Kb |
| Idioma del documento | Inglés |
APPLICATIO S I FOR ATIO
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LTC1051/LTC1053
U U W U APPLICATIO S I FOR ATIO
5. For unity-gain inverting configuration, all the alias 68dB value of Figure 7 decreases to 56dB if a (1k, 100k) frequencies are 80dB to 84dB down from the output signal resistor set is used to set the gain of –100. (Figures 6a, 6b). Combined with excellent THD under wide 7. When the LTC1051/LTC1053 are used as noninverting swing, the LTC1051/LTC1053 op amps make efficient amplifiers, all the previous approximate rules of thumb unity gain inverters. apply with the following exceptions: when the closed-loop For gain higher than –1, the “signal to alias” ratio de- gain is 10(V/V) and below, the “signal to alias” ratio is 1dB creases at an approximate rate of –6dB per decade of to 3dB less than the inverting case; when the closed-loop closed-loop gain (Figure 9). gain is 100(V/V), the degradation can be up to 9dB, especially when the input signal is much higher than the 6. For closed-loop gains of –10 or higher, the “signal to clock frequency (i.e. f alias” ratio degrades when the value of the feedback gain IN = 10kHz). setting resistor increases beyond 50k. For instance, the 8. The signal/alias ratio performance improves when the op amp has bandlimited loop gain. SYSTEM BUSY, ONLY ABORT COMMANDS ALLOWED STATUS: PAUSED RANGE: 11dBV 20dBV R2 10k 5V 68dB 15dB 0.1µF /DIV R1 100Ω – 1/2 90mV V P-P LTC1051 OUT 10kHz + 50pF –100 0.1 CENTER: 10 000Hz BW: 95.485Hz SPAN: 10 000Hz µF X: 5475Hz Y: –58.05dBV – 5V 1051/53 F07 6f f CLK – fIN IN =10kHz
Figure 7. Output Voltage Spectrum of 1/2 LTC1051 Operating as an Inverting Amplifier with a Gain of –100 and Amplifiying a 90mVP-P, 10kHz Input Signal. With a 9VP-P Output Swing the Measured 2nd Harmonic (20kHz) was 75 Down from the 10kHz Input Signal
10 90 VS = ±5V 9 f V 80 IN ≤10kHz S = ±8V, TA ≤85°C 8 70 V) 7 ± 6 60 VS = ±5V, TA ≤85°C 5 50 SWING ( ± 4 40 OUTV 3 VS = ±2.5V, TA ≤85°C 30 2 NEGATIVE SWING 1 20 POSITIVE SWING 0 OUTPUT SIGNAL TO ALIAS SIGNAL(S) RATIO (dB) 10 0 1k 2k 3k 4k 5k 6k 7k 8k 9k 10k 1 10 100 RL (LOAD RESISTANCE,Ω) INVERTING CLOSED-LOOP GAIN 1051/53 G08 1051/53 G09
Figure 8. Output Voltage Swing vs Load Figure 9. Signal to Alias Ratio vs Closed-Loop Gain
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U U W U APPLICATIO S I FOR ATIO
5. For unity-gain inverting configuration, all the alias 68dB value of Figure 7 decreases to 56dB if a (1k, 100k) frequencies are 80dB to 84dB down from the output signal resistor set is used to set the gain of –100. (Figures 6a, 6b). Combined with excellent THD under wide 7. When the LTC1051/LTC1053 are used as noninverting swing, the LTC1051/LTC1053 op amps make efficient amplifiers, all the previous approximate rules of thumb unity gain inverters. apply with the following exceptions: when the closed-loop For gain higher than –1, the “signal to alias” ratio de- gain is 10(V/V) and below, the “signal to alias” ratio is 1dB creases at an approximate rate of –6dB per decade of to 3dB less than the inverting case; when the closed-loop closed-loop gain (Figure 9). gain is 100(V/V), the degradation can be up to 9dB, especially when the input signal is much higher than the 6. For closed-loop gains of –10 or higher, the “signal to clock frequency (i.e. f alias” ratio degrades when the value of the feedback gain IN = 10kHz). setting resistor increases beyond 50k. For instance, the 8. The signal/alias ratio performance improves when the op amp has bandlimited loop gain. SYSTEM BUSY, ONLY ABORT COMMANDS ALLOWED STATUS: PAUSED RANGE: 11dBV 20dBV R2 10k 5V 68dB 15dB 0.1µF /DIV R1 100Ω – 1/2 90mV V P-P LTC1051 OUT 10kHz + 50pF –100 0.1 CENTER: 10 000Hz BW: 95.485Hz SPAN: 10 000Hz µF X: 5475Hz Y: –58.05dBV – 5V 1051/53 F07 6f f CLK – fIN IN =10kHz
Figure 7. Output Voltage Spectrum of 1/2 LTC1051 Operating as an Inverting Amplifier with a Gain of –100 and Amplifiying a 90mVP-P, 10kHz Input Signal. With a 9VP-P Output Swing the Measured 2nd Harmonic (20kHz) was 75 Down from the 10kHz Input Signal
10 90 VS = ±5V 9 f V 80 IN ≤10kHz S = ±8V, TA ≤85°C 8 70 V) 7 ± 6 60 VS = ±5V, TA ≤85°C 5 50 SWING ( ± 4 40 OUTV 3 VS = ±2.5V, TA ≤85°C 30 2 NEGATIVE SWING 1 20 POSITIVE SWING 0 OUTPUT SIGNAL TO ALIAS SIGNAL(S) RATIO (dB) 10 0 1k 2k 3k 4k 5k 6k 7k 8k 9k 10k 1 10 100 RL (LOAD RESISTANCE,Ω) INVERTING CLOSED-LOOP GAIN 1051/53 G08 1051/53 G09
Figure 8. Output Voltage Swing vs Load Figure 9. Signal to Alias Ratio vs Closed-Loop Gain
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