Electronics designer/consultant. Constant Current Pulse Generator (1 to 10 mA, pulse duration of 100 microsec. to 2ms, applied across 1K to 100Kohm resistive load).

For this project we require an experienced electronics engineer to help us design a circuit, part of a bigger electronics design. Please reach out only if you are a senior EE with relevant experience. The deliverable is the schematics of the circuit (no layout or fabrication needed at this stage). In addition to the schematics, we require the full model/reference of the key components (i.e. all the info needed to order them) and a detailed explanation (could be voice/video or written) that demonstrates that the design will meet our specifications and provides a rationale as to why it is the best solution. Specifications of the circuit (please see attached file): 1. Signal Inputs: 1 analog voltage signal (coming from an external MCU’s DAC). Range 0 to 5V or 0 to 3.3V, to be agreed. 2. Signal Outputs: two floating outputs (isolated from the circuit’s ground) across which the load will be connected. This circuit should be designed to operate with resistive loads with a nominal value between 1Kohm and 100Kohms. 3. The circuit generates current pulses across the resistive load. The amplitude of the pulses, in the range 1mA to 10mA, either positive or negative, is set by the analog input, and should be independent from the resistance of the load within the specific range of acceptable loads. The current pulse on the load tracks the profile of the voltage pulse seen at the input. Pulses will have a duration of 100 microseconds to 2ms. 4. The rising and falling edges of the pulses should be as fast as 5 microseconds (or 5% of the shortest pulses). 5. For safety reasons, it would be best to avoid having large DC voltages in the circuit (but can be discussed). 6. Throughout the duration of a pulse, the output current should not deviate from the ideal (square) output by more than 5%. This means that, if a step-up transformer is used, voltage-droop and rise-time should be considered and minimized, for the entire range of pulse duration required by the specifications (up to 2ms). 7. Compliance for various loads: a) for 100Kohm loads, Imax should be up to 1mA, b) for 10Kohm loads, Imax should be 10mA c) for 1Kohm loads, Imax should be also 10mA (clamped for safety). Please contact us only if you have demonstrable experience in a similar project. Mention this experience, in addition to other professional/academic background, in your proposal. This project requires an experienced EE.