Datasheet LT1226 (Analog Devices) - 7
| Manufacturer | Analog Devices |
| Description | Low Noise Very High Speed Operational Amplifier |
| Pages / Page | 8 / 7 — APPLICATI. S I FOR ATIO. AV = –25, CL = 1000pF. AV = +25, CL = 10,000pF. … |
| File Format / Size | PDF / 221 Kb |
| Document Language | English |
APPLICATI. S I FOR ATIO. AV = –25, CL = 1000pF. AV = +25, CL = 10,000pF. Compensation. TYPICAL APPLICATI. Cable Driving
Model Line for this Datasheet
Text Version of Document
LT1226
O U U W U APPLICATI S I FOR ATIO
frequency domain and in the transient response. The configurations (i.e., in a gain of 1000 it will have a photo of the small signal response with 1000pF load bandwidth of about 1MHz). The amplifier is stable in a shows 55% peaking. The large signal response with a noise gain of 25 so the ratio of the output signal to the 10,000pF load shows the output slew rate being limited by inverting input must be 1/25 or less. Straightforward gain the short circuit current. configurations of +25 or –24 are stable, but there are a few configurations that allow the amplifier to be stable for
AV = –25, CL = 1000pF AV = +25, CL = 10,000pF
lower signal gains (the noise gain, however, remains 25 or more). One example is the inverting amplifier shown in the typical applications sections below. The input signal has a gain of –RF/RIN to the output, but it is easily seen that this configuration is equivalent to a gain of –24 as far as the amplifier is concerned. Lag compensation can also be used to give a low frequency gain less than 25 with a high LT1226 AI04 frequency gain of 25 or greater. The example below has a The LT1226 can drive coaxial cable directly, but for best DC gain of 6, but an AC gain of +31. The break frequency pulse fidelity the cable should be doubly terminated with of the RC combination across the amplifier inputs should a resistor in series with the output. be at least a factor of 10 less than the gain bandwidth of the amplifier divided by the high frequency gain (in this case
Compensation
1/10 of 1GHz/31 or 3MHz). The LT1226 has a typical gain bandwidth product of 1GHz which allows it to have wide bandwidth in high gain
O U TYPICAL APPLICATI S Cable Driving
R3 + IN V 75 CABLE Ω
Lag Compensation
75 Ω LT1226 OUT V – R4 V R1 IN + 75Ω 1.2k LT1226 VOUT 200Ω – R2 50Ω 330pF 5k LT1226 TA04 LT1226 TA03
VOS Null Loop
1k AV = +6, f < 2MHz 300k 300k 1 VIN +
Compensation for Lower Closed-Loop Gains
8 LT1226 VOUT RF – 25k RIN VIN – 10k 10k 100pF 25Ω LT1226 VOUT RC + – LT1097 LT1226 TA05 100pF + RF AV = – ; R R F ≥ 24 × (RIN || RC) IN A LT1226 TA06 V = 1001 Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of circuits as described herein will not infringe on existing patent rights. 7
O U U W U APPLICATI S I FOR ATIO
frequency domain and in the transient response. The configurations (i.e., in a gain of 1000 it will have a photo of the small signal response with 1000pF load bandwidth of about 1MHz). The amplifier is stable in a shows 55% peaking. The large signal response with a noise gain of 25 so the ratio of the output signal to the 10,000pF load shows the output slew rate being limited by inverting input must be 1/25 or less. Straightforward gain the short circuit current. configurations of +25 or –24 are stable, but there are a few configurations that allow the amplifier to be stable for
AV = –25, CL = 1000pF AV = +25, CL = 10,000pF
lower signal gains (the noise gain, however, remains 25 or more). One example is the inverting amplifier shown in the typical applications sections below. The input signal has a gain of –RF/RIN to the output, but it is easily seen that this configuration is equivalent to a gain of –24 as far as the amplifier is concerned. Lag compensation can also be used to give a low frequency gain less than 25 with a high LT1226 AI04 frequency gain of 25 or greater. The example below has a The LT1226 can drive coaxial cable directly, but for best DC gain of 6, but an AC gain of +31. The break frequency pulse fidelity the cable should be doubly terminated with of the RC combination across the amplifier inputs should a resistor in series with the output. be at least a factor of 10 less than the gain bandwidth of the amplifier divided by the high frequency gain (in this case
Compensation
1/10 of 1GHz/31 or 3MHz). The LT1226 has a typical gain bandwidth product of 1GHz which allows it to have wide bandwidth in high gain
O U TYPICAL APPLICATI S Cable Driving
R3 + IN V 75 CABLE Ω
Lag Compensation
75 Ω LT1226 OUT V – R4 V R1 IN + 75Ω 1.2k LT1226 VOUT 200Ω – R2 50Ω 330pF 5k LT1226 TA04 LT1226 TA03
VOS Null Loop
1k AV = +6, f < 2MHz 300k 300k 1 VIN +
Compensation for Lower Closed-Loop Gains
8 LT1226 VOUT RF – 25k RIN VIN – 10k 10k 100pF 25Ω LT1226 VOUT RC + – LT1097 LT1226 TA05 100pF + RF AV = – ; R R F ≥ 24 × (RIN || RC) IN A LT1226 TA06 V = 1001 Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of circuits as described herein will not infringe on existing patent rights. 7
