Technology comparison — CMOS vs. TTL switching speed Modern digital IC technologies have evolved. Today, the switching speed of CMOS logic families is generally ________ when compared with TTL under similar conditions.

Introduction / Context:
Historically, TTL was known for faster switching than early CMOS. However, advances in CMOS processes (submicron geometries, low gate capacitances) have dramatically improved performance. Understanding current capabilities helps in selecting logic families for speed, power, and signal integrity.

Given Data / Assumptions:

• Comparison is qualitative/generic across mainstream families.
• Operating within datasheet-recommended loads and supply voltages.
• No exotic specialized high-speed ECL/PECL included.

Concept / Approach:
Modern CMOS (e.g., 74HC, 74AC, 74LVC, 74AUP variants) achieves propagation delays comparable to or better than many TTL families while consuming less static power. Therefore, a fair statement is that CMOS switching speed is competitive with TTL in contemporary designs.

Step-by-Step Solution:

Verification / Alternative check:
Datasheets show typical propagation delays in the low-nanosecond to tens-of-nanoseconds range for both modern TTL-compatible and CMOS families, confirming comparable speeds for general-purpose parts.

Why Other Options Are Wrong:

• “Three times” or “twice” that of TTL: Overly specific and not universally accurate.
• “Slower than TTL”: Outdated generalization; many CMOS parts are as fast or faster.

Common Pitfalls:
Assuming all CMOS is the same; in reality, families differ (HC vs. AC vs. LVC). Always consult the specific family datasheet for precise timing numbers.

Final Answer:
competitive with TTL