Characterizing Custom Analog Blocks in Mixed-Signal Microcontrollers

This article describes our use of the Analog FastSPICE circuit simulator (AFS) from Berkeley Design Automation for verifying the design of a crystal oscillator, transistor-level closed-loop PLL simulation, and characterizing a 10-bit, 8-channel ADC. With our traditional SPICE simulator, we had to wait for two to three days for the longer simulations to complete. AFS provides identical results in overnight runs.