NE555

The NE555 is the legendary timing IC designed by Hans Camenzind for Signetics in 1971 and still manufactured today by TI, STMicroelectronics, onsemi, NXP, and dozens of second sources. Its enduring popularity comes from an elegant internal architecture — two comparators, an SR flip-flop, a discharge transistor and a totem-pole output — that lets designers build astable oscillators, monostable one-shots, PWM generators and pulse-width modulators with just two external resistors and one capacitor.

The device operates from 4.5 V to 15 V (up to 18 V absolute maximum) and can source or sink 200 mA on its output pin, which means it drives small relays, LEDs, and even loudspeakers directly without a transistor buffer. Timing accuracy is roughly 1% at 25 °C and drifts about 50 ppm/°C, adequate for indicator flashers, tone generation and coarse control loops but not for precision timing (use a DS3231 RTC or a CMOS 555 like the LMC555 for tighter specs).

Two major variants dominate modern BOM: the classic bipolar NE555 with 10 mA supply current and the CMOS TLC555 / LMC555 with 250 µA supply current and rail-near output swing. For battery-powered designs, always specify the CMOS version. The NE555 remains one of the highest-volume ICs ever sold — annual shipments exceed one billion units — which means pricing is stable and counterfeit risk is low when buying from authorized channels.

In our Shenzhen warehouse we stock NE555P (DIP-8), NE555DR (SOP-8) and NE555DRG4 (green SOP-8) directly from TI, with MOQ of 2,000 pcs on reel or 100 pcs loose for prototypes.