A Dynamic Slew Correction Circuit for Low Noise Silicon Detector Pre-amplifiers
This manuscript introduces a transistor level technique that results in simultaneous improved slew rate and noise performance for applications where only the final settled output voltage over a predefined time frame is important - such as silicon detector read out charge-to-voltage reset amplifiers. For large signal swings, slew limitation is detected and compensated dynamically. For non-slew limiting situations the amplifier operates normally in a low noise mode. To verify correct operation of the dynamic slew correction circuit, a single-ended, pulse-reset charge amplifier was fabricated in IBM 130 nm 6M/2P technology. The test amplifier achieved a slew rate of 1V/120 ns with a 50 pF load and a total of ~ 23μVrms noise over 100 kHz-20 MHz. The reported amplifier also serves as the basis for the high performance front-end amplifier in the LPD detector system for the European XFEL.