전자부품 데이터시트 검색엔진 |
|
AD8631 데이터시트(PDF) 11 Page - Analog Devices |
|
AD8631 데이터시트(HTML) 11 Page - Analog Devices |
11 / 12 page AD8631/AD8632 –11– REV. 0 Table II. Snubber Network Values for Large Capacitive Loads CLOAD Rx Cx 600 pF 300 Ω 1 nF 1 nF 300 Ω 1 nF 10 nF 90 Ω 8 nF TOTAL HARMONIC DISTORTION + NOISE The AD863x family offers a low total harmonic distortion, which makes this amplifier ideal for audio applications. Figure 27 shows a graph of THD + N, which is ~0.02% @ 1 kHz, for a 1.8 V supply. At unity gain in an inverting configuration the value of the Total Harmonic Distortion + Noise stays consistently low over all volt- ages supply ranges. FREQUENCY – Hz 0.1 0.001 10 20k 0.01 1 10 100 1k 10k VS = 1.8V VS = 5V INVERTING AV = 1 Figure 27. THD + N vs. Frequency Graph AD8632 Turn-On Time The low voltage, low power AD8632 features an extraordinary turn on time. This is about 500 ns for VSY = 5 V, which is impressive considering the low supply current (300 µA typical per amplifier). Figure 28 shows a scope picture of the AD8632 with both channels configured as followers. Channel A has an input signal of 2.5 V and channel B has the input signal at ground. The top waveform shows the supply voltage and the bottom waveform reflects the response of the amplifier at the output of Channel A. TIME – 200ns/DIV 0 0 0 0 0 0 0 VS = 5V AV = 1 VIN = 2.5V STEP 0V 0V Figure 28. AD8632 Turn-On Time A MICROPOWER REFERENCE VOLTAGE GENERATOR Many single-supply circuits are configured with the circuit biased to one-half of the supply voltage. In these cases, a false-ground reference can be created by using a voltage divider buffered by an amplifier. Figure 28 shows the schematic for such a circuit. The two 1 M Ω resistors generate the reference voltages while drawing only 0.9 µA of current from a 1.8 V supply. A capacitor connected from the inverting terminal to the output of the op amp provides compensation to allow a bypass capacitor to be connected at the reference output. This bypass capacitor helps establish an ac ground for the reference output. AD8631 10k 0.022 F VREF 0.9V TO 2.5V 1 F 1 F 1M 1.8V TO 5V 100 1M Figure 29. A Micropower Reference Voltage Generator MICROPHONE PREAMPLIFIER The AD8631 is ideal to use as a microphone preamplifier. Figure 30 shows this implementation. AD8631 VOUT R3 220k 1.8V VREF = 0.9V R2 22k C1 0.1 F 1.8V R1 2.2k ELECTRET MIC AV = R3 R2 VIN Figure 30. A Microphone Preamplifier R1 is used to bias an electret microphone and C1 blocks dc voltage from the amplifier. The magnitude of the gain of the amplifier is approximately R3/R2 when R2 ≥ 10 R1. VREF should be equal to 1/2 1.8 V for maximum voltage swing. Direct Access Arrangement for Telephone Line Interface Figure 31 illustrates a 1.8 V transmit/receive telephone line interface for 600 Ω transmission systems. It allows full duplex transmission of signals on a transformer-coupled 600 Ω line in a differential manner. Amplifier A1 provides gain that can be adjusted to meet the modem output drive requirements. Both A1 and A2 are configured to apply the largest possible signal on a single supply to the transformer. Amplifier A3 is configured as a difference amplifier for two reasons: (1) It prevents the transmit signal from interfering with the receive signal and (2) it extracts the receive signal from the transmission line for amplification by A4. A4’s gain can be adjusted in the same manner as A1’s to meet the modem’s input signal requirements. Standard resistor values permit the use of SIP (Single In-line Package) format resistor arrays. Couple this with the AD8631/ |
유사한 부품 번호 - AD8631 |
|
유사한 설명 - AD8631 |
|
|
링크 URL |
개인정보취급방침 |
ALLDATASHEET.CO.KR |
ALLDATASHEET 가 귀하에 도움이 되셨나요? [ DONATE ] |
Alldatasheet는? | 광고문의 | 운영자에게 연락하기 | 개인정보취급방침 | 링크교환 | 제조사별 검색 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 |