Dual 555 timer in a 14-SOIC — what the 2.1 MHz ceiling means
The TLC556CDR packs two independent 555-type timer/oscillator stages into a single 14-SOIC (0.154″ wide, 3.90 mm body). The 2.1 MHz maximum frequency sets the upper bound for astable oscillation or monostable pulse generation. Supply current is 720 µA typical — roughly one-tenth of a bipolar 556 — which makes this part a natural fit for battery-operated or power-budgeted boards where the timer runs continuously. The 2V to 15V supply range covers 3.3V, 5V, and 12V rails without an extra regulator; just watch the output voltage swing at 2V — it tracks VCC minus about 0.1V at light load.
Do not use it in an automotive cabin or an outdoor telecom cabinet without a temperature qualification review; the timing drift below 0°C is unspecified. The 0.154″ body width fits a narrow SOIC land pattern.