Datasheet LT1206 (Analog Devices) - 8
| Manufacturer | Analog Devices |
| Description | 250mA/60MHz Current Feedback Amplifier |
| Pages / Page | 18 / 8 — siMpliFieD scheMaTic. applicaTions inForMaTion. Capacitive Loads. … |
| File Format / Size | PDF / 372 Kb |
| Document Language | English |
siMpliFieD scheMaTic. applicaTions inForMaTion. Capacitive Loads. Feedback Resistor Selection
Model Line for this Datasheet
Text Version of Document
LT1206
siMpliFieD scheMaTic
V+ TO ALL CURRENT Q5 SOURCES Q10 Q2 D1 Q11 Q18 Q1 Q6 Q15 Q17 Q9 V– 1.25k V– 50Ω CC +IN –IN RC COMP OUTPUT V+ SHUTDOWN V+ Q12 Q3 Q8 Q16 Q14 Q4 D2 Q13 Q7 V– 1206 SS
applicaTions inForMaTion
The LT1206 is a current feedback amplifier with high output line when the response has 0.5dB to 5dB of peaking. The current drive capability. The device is stable with large curves stop where the response has more than 5dB of capacitive loads and can easily supply the high currents peaking. required by capacitive loads. The amplifier will drive low For resistive loads, the COMP pin should be left open (see impedance loads such as cables with excellent linearity section on capacitive loads). at high frequencies.
Capacitive Loads Feedback Resistor Selection
The LT1206 includes an optional compensation network The optimum value for the feedback resistors is a function for driving capacitive loads. This network eliminates most of the operating conditions of the device, the load imped- of the output stage peaking associated with capacitive ance and the desired flatness of response. The Typical AC loads, allowing the frequency response to be flattened. Performance tables give the values which result in the Figure 1 shows the effect of the network on a 200pF load. highest 0.1dB and 0.5dB bandwidths for various resistive Without the optional compensation, there is a 5dB peak loads and operating conditions. If this level of flatness is at 40MHz caused by the effect of the capacitance on the not required, a higher bandwidth can be obtained by use output stage. Adding a 0.01µF bypass capacitor between the of a lower feedback resistor. The characteristic curves of output and the COMP pins connects the compensation and Bandwidth vs Supply Voltage indicate feedback resistors completely eliminates the peaking. A lower value feedback for peaking up to 5dB. These curves use a solid line when resistor can now be used, resulting in a response which the response has less than 0.5dB of peaking and a dashed 1206fb 8 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Small-Signal Bandwidth Typical Performance Characteristics Simplified Schematic Applications Information Package Description Revision History Related Parts
siMpliFieD scheMaTic
V+ TO ALL CURRENT Q5 SOURCES Q10 Q2 D1 Q11 Q18 Q1 Q6 Q15 Q17 Q9 V– 1.25k V– 50Ω CC +IN –IN RC COMP OUTPUT V+ SHUTDOWN V+ Q12 Q3 Q8 Q16 Q14 Q4 D2 Q13 Q7 V– 1206 SS
applicaTions inForMaTion
The LT1206 is a current feedback amplifier with high output line when the response has 0.5dB to 5dB of peaking. The current drive capability. The device is stable with large curves stop where the response has more than 5dB of capacitive loads and can easily supply the high currents peaking. required by capacitive loads. The amplifier will drive low For resistive loads, the COMP pin should be left open (see impedance loads such as cables with excellent linearity section on capacitive loads). at high frequencies.
Capacitive Loads Feedback Resistor Selection
The LT1206 includes an optional compensation network The optimum value for the feedback resistors is a function for driving capacitive loads. This network eliminates most of the operating conditions of the device, the load imped- of the output stage peaking associated with capacitive ance and the desired flatness of response. The Typical AC loads, allowing the frequency response to be flattened. Performance tables give the values which result in the Figure 1 shows the effect of the network on a 200pF load. highest 0.1dB and 0.5dB bandwidths for various resistive Without the optional compensation, there is a 5dB peak loads and operating conditions. If this level of flatness is at 40MHz caused by the effect of the capacitance on the not required, a higher bandwidth can be obtained by use output stage. Adding a 0.01µF bypass capacitor between the of a lower feedback resistor. The characteristic curves of output and the COMP pins connects the compensation and Bandwidth vs Supply Voltage indicate feedback resistors completely eliminates the peaking. A lower value feedback for peaking up to 5dB. These curves use a solid line when resistor can now be used, resulting in a response which the response has less than 0.5dB of peaking and a dashed 1206fb 8 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Small-Signal Bandwidth Typical Performance Characteristics Simplified Schematic Applications Information Package Description Revision History Related Parts
