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In this paper, the independent rise and fall edge dead time generator for switching control signal is presented. The scheme of the proposed circuit is based on the monostable multivibrator circuit together with the toggle circuit that use JK flip-flop to operate, OR Gate, AND Gate and NOT Gate. The obtained results from simulation and experiment affirm that the dead time at rise and fall edge of switching obtained from the proposed scheme can be independently controlled. The control ability is achieved by adjusting the resistance of the resistor or capacitance of the capacitor that are combined in monostable multivibrator circuit. The proposed circuit is easily implemented and provides the precise dead time duration, at least in nanosecond level. Furthermore, it can operate effectively at high frequency condition. It hence can be employed in various applications. [ABSTRACT FROM PUBLISHER]

An improved model in defining the dead time (tD) response for Silicon Avalanche Photodiode (Si APD) is presented in this paper. The generation of a mathematical model for Si APD is used to characterize the performance of passively quenched Si APD. For this purpose, quenching time (tq) and recharging time (tr) models are implemented to obtain tD less than 50 ns. Therefore, the value of quenching resistor (RL) should be minimized to reduce the recharge duration of time constant RLC. By concerning various values of RL and the influence of parasitic capacitance (C), tr and tq are analyzed in defining tD for Si APD, which is working in Geiger's mode. [ABSTRACT FROM PUBLISHER]

A multi-channel charge readout integrated circuit (IC) which converts detector charge to analog voltage without dead time for X-ray security imaging is described. The charge readout IC provides 32 channels of circuit having a max dynamic range of 15 bit and is comprised of charge amplifier gain control, timing generator, shift register chain, charge amplifier array, sample/hold (S/H) stage amplifier and driver etc. It was fabricated using 0.6 um standard CMOS process, and occupies a die area of 2.9 mm × 7.1 mm. It operates at 4 MHz, consumes 45 mW from 5 V supply and 3.5 V as reference, and has a demonstrated output noise performance of 90 uVrms on 31.5 pF of charge amplifier gain capacitance and 52 pF of photodiode (PD) terminal capacitance. [ABSTRACT FROM PUBLISHER]