Features for the THS4140EVM
THS4140 high-speed operational amplifier EVM features include:
- Voltage supply operation range: 5-V to +/- 15-V operation (see the device datasheet)
- Single and differential input and output capability
- Nominal 50 ohm input and output termination resistors. They can be configured according to the application requirement.
- Vocm direct input control (see schematic and the device datasheet)
- Vocm pin can be controlled via transformer center-tap (see schematic)
- Shutdown pin control, JU1 (if applicable to the device, see the device datasheet)
- Input and output transformer footprints for changing single-ended signals to differential signals
- Footprint for high-precision, balanced feedback and gain resistors (0.01% or better)
- Footprints for low-pass filter implementation
- Footprints for antialiasing filter implementation
- Differential probe terminals on input and output nodes for differential probe insertion
- Various GND and signal test points on the PCB
- Circuit schematic printed on the back of the EVM
- A good example of high-speed amplifier PCB design and layout
Description for the THS4140EVM
The THS4140EVM is a good example of PCB design and layout for high-speed operational amplifier applications. It is a complete circuit for the high-speed operational amplifier. The EVM is made of the THS4140 high-speed operational amplifier, a number of passive components, and various features and footprints that enable the user to experiment, test, and verify various operational amplifier circuit implementations. The board measures 4.5 inches in length by 2.5 inches in width. Initially, this board is populated for a single-ended input amplifier. The outputs (Vo+ and Vo-) can be tested differentially or single ended. Gain is set to one and can be changed by changing the ratios of the feedback and gain resistors (see the device datasheet for recommended resistor values). The user may populate various footprints on the evaluation module board to verify filter designs or perform other experiments. Each input is terminated with a 50 ohm resistor to provide correct line-impedance matching.