NE555 - 200mA Precision Timer IC 100kHz | Texas Instruments
MPN: NE555 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.55 | $0.55 |
| 10 | $0.42 | $4.20 |
| 100 | $0.31 | $31.00 |
| 500 | $0.26 | $130.00 |
| 1,000 | $0.21 | $210.00 |
Drop-in alternatives for NE555 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
NA555P
β Drop-Inπ Reference alternative (not in catalog)
SE555N
β Drop-Inπ Reference alternative (not in catalog)
LM555N
β Drop-Inπ Reference alternative (not in catalog)
TLC555CP
β Drop-Inπ Reference alternative (not in catalog)
NE555
β Drop-Inβ In Stock
$0.21 / Unit
View Datasheet βNE555
β Drop-Inβ In Stock
$0.21 / Unit
View Datasheet βNE555 Maximum Ratings & Electrical Characteristics
| Function | 555 Type, Timer/Oscillator (Single) |
| Operation Modes | Astable or Monostable |
| Maximum Frequency | 100 kHz |
| Supply Voltage Range | 4.5 V to 16 V |
| Output Current | 200 mA (sink or source) |
| Timing Range | Microseconds to Hours |
| Duty Cycle | Adjustable |
| Output | TTL-Compatible |
| Package | 8-PDIP |
| Mounting Type | Through Hole |
| Technology | Bipolar |
| Operating Temperature | 0C to 70C (NE commercial grade) |
| Temperature Stability | [DATA_NEEDED: timing drift vs temperature] |
| Reset Function | Yes, overrides output |
| RoHS Status | Compliant |
NE555 Pin Configuration
| Pin 1 | GND β Ground reference |
| Pin 2 | TRIG β Trigger, starts timing when pulled below 1/3 VCC |
| Pin 3 | OUT β Output, sinks or sources up to 200 mA, TTL-compatible |
| Pin 4 | RESET β Active-low reset, overrides output when below 0.7V |
| Pin 5 | CONT β Control voltage, access to 2/3 VCC divider node; decouple with 0.01 uF |
| Pin 6 | THRES β Threshold, ends timing when above 2/3 VCC |
| Pin 7 | DISCH β Discharge, open-collector for timing capacitor |
| Pin 8 | VCC β Supply voltage, 4.5V to 16V |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this digital IC. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
NE555 is suitable for 6 applications: LED Flashers and Pulse Generators, PWM Motor Speed Control, Tone and Alarm Circuits, Clock Sources for Digital Logic, Power-On Reset and Sequencing Delays, Sensor and Hobby Automation Timers.
LED Flashers and Pulse Generators
The NE555 excels as an LED flasher or pulse generator because its astable mode needs only two resistors and one capacitor to set blink rate, and its 200 mA output drives LED strings directly without a buffer transistor. Operating from a 5V to 15V supply at up to 100 kHz, it covers slow status blinkers through fast pulse trains. The adjustable duty cycle lets designers set asymmetric on/off ratios; keeping the control-voltage pin decoupled with 0.01 uF suppresses false triggering from supply noise.
Recommended
PWM Motor Speed Control
In DC motor speed control, the NE555 generates a PWM carrier whose duty cycle is varied by a potentiometer or control voltage. Its bipolar output stage sources or sinks 200 mA, adequate for small motors or for driving an external power MOSFET gate through a driver. Timing stability from the 1/3-2/3 VCC comparator thresholds gives repeatable PWM frequency across a 4.5V-16V supply. The 100 kHz capability supports PWM frequencies above audible range, eliminating motor whine in consumer and industrial applications.
Recommended
Tone and Alarm Circuits
The NE555's astable oscillator directly drives speakers, piezo buzzers, and alarm sounders thanks to its 200 mA output current - no amplification stage needed. Frequency is programmed by two resistors and a capacitor per f = 1.44/((R1+2R2)C), enabling sirens, doorbells, and continuity testers. Two 555s can be cascaded (one as low-frequency modulator, one as audio oscillator) to create siren effects. Supply operation from 4.5V to 16V suits both battery and wall-adapter powered alarm products.
Recommended
Clock Sources for Digital Logic
The NE555 supplies TTL-compatible clock pulses for counters, shift registers, and microcontroller-less digital circuits. Its output swings near ground and VCC with 200 mA drive, directly clocking 74-series logic families. Designers select RC values for clock frequencies up to the 100 kHz device limit, ample for slow sequential logic. Supply-voltage-dependent timing means clock frequency shifts slightly with rail variation - acceptable for non-critical clocks, but a crystal oscillator should be used where frequency accuracy below a few percent is required.
Recommended
Power-On Reset and Sequencing Delays
In monostable mode, the NE555 creates precise power-on delays from microseconds to hours, generating delayed enable signals for power sequencing in industrial equipment. The single external RC network sets the interval deterministically, and the reset pin allows immediate override. Its 4.5V-16V supply range matches common industrial rails, while the 200 mA output can directly drive relay coils or optocoupler LEDs. The 1/3-2/3 VCC thresholds provide supply-proportional immunity to rail sag during startup transients.
Recommended
Sensor and Hobby Automation Timers
The NE555 implements touch switches, interval timers, and trigger circuits for hobby and light-industrial automation. Its high-impedance trigger comparator (referenced to 1/3 VCC) responds to capacitive touch plates and sensor outputs, while the monostable output duration is set by a single RC pair. The through-hole 8-PDIP package suits prototyping and educational kits. Designers should note the bipolar NE555 draws several milliamps of quiescent current; battery-powered sensor nodes benefit from the CMOS TLC555 in the same footprint.
Recommended
Recommended Products Summary
Engineering reference data for NE555 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | NA555P | LM555N | TLC555CP | NE555 (ST) |
|---|---|---|---|---|---|
| Package | 8-PDIP | 8-PDIP - same | 8-PDIP - same | 8-PDIP - same | 8-DIP - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | STMicroelectronics |
| Technology | Bipolar | Bipolar | Bipolar (improved) | CMOS | Bipolar |
| Output Current | 200 mA | 200 mA | 200 mA | ~100 mA sink / 10 mA source | 200 mA |
| Supply Voltage | 4.5 V to 16 V | 4.5 V to 16 V | 4.5 V to 16 V | 2 V to 15 V | 4.5 V to 16 V |
| Temperature Range | 0C to 70C | -40C to +85C | 0C to 70C | 0C to 70C | [DATA_NEEDED] |
| Max Frequency | 100 kHz | 100 kHz | 100 kHz | 2.1 MHz (higher) | 100 kHz |
| Quiescent Current | [DATA_NEEDED: typ supply current mA] | [DATA_NEEDED] | [DATA_NEEDED] | ~170 uA (much lower) | [DATA_NEEDED] |
Key Differentiators
- 200 mA output drive without external buffer (vs TLC555CP)
- Lower cost than improved bipolar variants (vs LM555N)
- Industrial temperature option in same footprint (vs NA555P)
Design Notes
Decouple the VCC pin with a 0.1 uF ceramic capacitor placed within 5 mm of pin 8, and tie the CONT pin (pin 5) to ground through 0.01 uF. The NE555's bipolar output stage draws large transient currents during output transitions; without local decoupling, these transients couple into the internal divider and cause timing jitter or double-triggering. Keep the timing capacitor's ground return separate from the output load ground.
Astable duty cycle is always above 50% with the standard two-resistor configuration because the capacitor charges through R1+R2 but discharges only through R2. Add a diode across R2 to achieve duty cycles below 50%, or use the CMOS TLC555 variant. Also never pull RESET (pin 4) floating - tie it to VCC if unused, or noise will randomly reset the timer.
The bipolar NE555 draws several milliamps of quiescent supply current regardless of load, making it unsuitable for coin-cell or long-life battery designs. Where battery life matters, drop in the pin-compatible TLC555 (approximately 170 uA typical). Conversely, when driving inductive loads like relays from the 200 mA output, add a flyback diode across the load to protect the output stage.
Compliance Information
RoHS compliance per TI product page and DigiKey listing; detailed REACH/halogen status requires checking the specific ordering suffix on ti.com.
