buf_AD Digital Buffer Threshold Output

Application

This circuit demonstrates the buf_AD digital buffer as a simple logic-level driver. A 5 V input drives the buffer above its threshold, and a 10 k load provides an output reference for the operating point result.

Design Context

VIN drives the input pin, U1 compares that input against its VTH setting, and RLOAD connects the output to ground. The probes show the applied input level and the resulting buffered output level.

Expected Behavior

With VIN at 5 V and VTH at 2.5 V, the operating point table should show Vout near the configured VHIGH value of 5 V. Reducing VIN below VTH should drive the output low.

Key Values

• VIN is 5 V.
• VTH is 2.5 V.
• VHIGH is 5 V.
• RLOAD is 10 k.

Suggested Experiments

• Lower VIN below 2.5 V and rerun the operating point to see the output switch low.
• Change VTH to model a different input threshold.
• Change VHIGH to match another logic rail.

Featured Component

buf_AD Digital Buffer is an ngspice-compatible threshold buffer model that converts an input voltage into a low or high output level for logic-style demonstrations.