Overview
The NE556N, produced by Texas Instruments, is a dual monolithic timing circuit that integrates two independent timing circuits similar to the NA555, NE555, SA555, or SE555 types in a single package. This device is highly stable and capable of producing accurate time delays or oscillation. It operates in both astable and monostable modes, with timing controlled by external resistor-capacitor (RC) networks. The NE556N is widely used in various applications requiring precise timing and is compatible with TTL inputs, making it versatile for a range of electronic systems.
Key Specifications
| Parameter | Unit | Min. | Typ. | Max. |
|---|---|---|---|---|
| VCC (Supply Voltage) | V | 4.5 | - | 16 |
| TA (Operating Temperature) | °C | 0 | - | 70 |
| VT (Threshold Voltage Level) | V | 8.8 | 10 | 11.2 |
| VTRIG (Trigger Voltage Level) | V | 4.5 | 5 | 5.6 |
| ITRIG (Trigger Current) | μA | 0.5 | 2 | - |
| VRESET (Reset Voltage Level) | V | 0.3 | 0.7 | 1 |
| IO (Output Current) | mA | -200 | - | 200 |
| tr (Output Rise Time) | ns | 100 | 300 | - |
| tf (Output Fall Time) | ns | 100 | 300 | - |
Key Features
- Two independent timing circuits in a single package, similar to NA555, NE555, SA555, or SE555 types.
- Astable or monostable operation with external RC timing control.
- TTL-compatible output capable of sinking or sourcing up to 200 mA.
- Active pullup or pulldown.
- Adjustable duty cycle.
- Trigger and threshold levels can be altered using the control-voltage pin.
- Reset input to initiate a new timing cycle.
- Low-impedance path between discharge pin and ground when output is low.
Applications
- Precision timers from microseconds to hours.
- Pulse-shaping circuits.
- Missing-pulse detectors.
- Tone-burst generators.
- Pulse-width modulators.
- Pulse-position modulators.
- Sequential timers.
- Pulse generators.
- Frequency dividers.
- Industrial controls.
- Touch-tone encoders.
- Fingerprint and iris biometrics.
- RFID readers.
Q & A
- What is the operating temperature range of the NE556N?
The operating temperature range of the NE556N is from 0°C to 70°C.
- What is the supply voltage range for the NE556N?
The supply voltage range for the NE556N is from 4.5 V to 16 V.
- Can the NE556N operate in both astable and monostable modes?
- What is the maximum output current of the NE556N?
The NE556N can sink or source up to 200 mA of output current.
- How are the trigger and threshold levels controlled in the NE556N?
The trigger and threshold levels can be altered using the control-voltage pin (CONT).
- What is the purpose of the reset input in the NE556N?
The reset input (RESET) overrides all other inputs and is used to initiate a new timing cycle.
- What happens when the output of the NE556N is low?
When the output is low, a low-impedance path is provided between the discharge pin (DISCH) and the ground pin (GND).
- Is the NE556N compatible with TTL inputs?
- What are some typical applications of the NE556N?
- How many independent timing circuits does the NE556N contain?
