A slew rate self-adjusting 2×VDD output buffer With PVT compensation

Abstract

A novel PVT (Process, Voltage, Temperature) detection and compensation technique is proposed to automatically adjust the slew rate of a 2×VDD output buffer. The threshold voltage (Vth) of PMOSs and NMOSs varying with process, voltage, and temperature deviation could be detected, respectively. The proposed design is implemented using a typical 90 nm CMOS process to justify the performance. By adjusting output currents, the slew rate of output signal could be compensated over 38% and the maximum data rate with compensation is 345 MHz.

A 5 V-to-32 V Input PVT-Robust Charge-Pump Circuit with Adjustable Output in a 0.18 μm BCD Process

“…The specific deviation values are shown in Table 2. Figures [10][11][12] show that a Monte Carlo simulation was carried out in 500 samples when VBB = 24 V, A1A2 = 00, A1A2 = 01, and A1A2 = 10 to evaluate the sensitivity of the output voltage under process variation and mismatch conditions. The worst case of the process sensitivity (σ/µ) is 0.1%.…”

“…It can be seen from Equation (12) above that VCP increases continuously within t 2 . The parameters of r 1 , r 2 , C 1 , C 2 through the on-resistance Ron of the switch transistor, the pump capacitance C f , the load capacitance C L , the load resistance R L affect the charging rate in the t 2 stage.…”

“…The amplifier's gain can be compensated by tracking the PVT variations by an auxiliary single-pole amplifier [11]. Alternatively, the circuit's operating environment can be directly detected by PVT detector to regulate the circuit [12][13][14][15]. In this design, adjusting the amplifier's reference voltage under various PVT situations can precisely control the output voltage by the regulation system.…”

“…In addition, the current process corner can be judged according to the fluctuation of the VTH, while temperature variations can also impact the VTH. It is likely to generate overlapping phenomena and make it impossible to identify the process corners if the temperature detection range is too large [12].…”