 |
Motore di ricerca datesheet componenti elettronici |
|
|
Motore di ricerca datesheet componenti elettronici |
|
AD797AN Scheda tecnica(PDF) 14 Page - Analog Devices |
|
||||||||||||||||||||||||||||||
AD797AN Scheda tecnica(HTML) 14 Page - Analog Devices |
|
|
14 / 20 page  AD797 Rev. F | Page 14 of 20 7 * * VOUT +VS –VS AD797 R1 RS IIN CS 6 3 4 100Ω 600Ω 20pF TO 120pF 2 *USE THE POWER SUPPLY BYPASSING SHOWN IN FIGURE 35. Figure 39. I-to-V Converter Connection THE INVERTING CONFIGURATION The inverting configuration (see Figure 40) presents a low input impedance, R1, to the source. For this reason, the goals of both low noise and input buffering are at odds with one another. Nonetheless, the excellent dynamics of the AD797 makes it the preferred choice in many inverting applications, and with careful selection of feedback resistors, the noise penalties are minimal. Some examples are presented in Table 5 and Figure 40. 7 * * VOUT VIN +VS –VS AD797 R2 RL RS R1 CL 6 3 4 2 *USE THE POWER SUPPLY BYPASSING SHOWN IN FIGURE 35. Figure 40. Inverting Amplifier Connection Table 5. Values for Inverting Circuit Gain R1 R2 CL Noise (Excluding RS) −1 1 kΩ 1 kΩ ≈20 pF 3.0 nV/√Hz −1 300 Ω 300 Ω ≈10 pF 1.8 nV/√Hz −10 150 Ω 1500 Ω ≈5 pF 1.8 nV/√Hz DRIVING CAPACITIVE LOADS The capacitive load driving capabilities of the AD797 are displayed in Figure 41. At gains greater than 10, usually no special precautions are necessary. If more drive is desirable, however, the circuit shown in Figure 42 should be used. For example, this circuit allows a 5000 pF load to be driven cleanly at a noise gain ≥2. 100nF 10nF 1pF 100 10 11 1nF 100pF 10pF CLOSED-LOOP GAIN k Figure 41. Capacitive Load Drive Capability vs. Closed-Loop Gain 7 * * VOUT VIN +VS –VS AD797 C1 20pF 200pF 6 3 4 2 33Ω 100Ω 1kΩ 1kΩ *USE THE POWER SUPPLY BYPASSING SHOWN IN FIGURE 35. Figure 42. Recommended Circuit for Driving a High Capacitance Load SETTLING TIME The AD797 is unique among ultralow noise amplifiers in that it settles to 16 bits (<150 μV) in less than 800 ns. Measuring this performance presents a challenge. A special test circuit (see Figure 43) was developed for this purpose. The input signal was obtained from a resonant reed switch pulse generator, available from Tektronix as calibration Fixture No. 067-0608-00. When open, the switch is simply 50 Ω to ground and settling is purely a passive pulse decay and inherently flat. The low repetition rate signal was captured on a digital oscilloscope after being amplified and clamped twice. The selection of plug-in for the oscilloscope was made for minimum overload recovery. |
Codice articolo simile - AD797AN |
|
Descrizione simile - AD797AN |
|
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEETIT.COM |
| Lei ha avuto il aiuto da alldatasheet? [ DONATE ] |
Di alldatasheet | Richest di pubblicita | contatti | Privacy Policy | scambio Link | Ricerca produttore All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
Italian ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
