Abstract:
This letter presents an aging-robust 32-MHz RC frequency reference based on a frequency-locked-loop (FLL). With a temperature compensation scheme that combines BJTs and aging-robust diffusion resistors, the FLL achieves ±1550-ppm inaccuracy from $-40~^{\circ }$ C to $125~^{\circ }$ C after batch calibration and a low-cost 1-point trim, which increases to ±2350-ppm …