LM393 Voltage Comparator Datasheet
Description:
The LM393 is a high-speed, low-power voltage comparator ideal for general-purpose comparator applications. It operates from a single power supply ranging from 2V to 36V and offers high gain and low input bias current.
Features:
* Operates from 2V to 36V single power supply
* High open-loop gain (200,000 typical)
* Input bias current: 50nA maximum
* Output short circuit protection
* Typically draws only 100μA
* Output compatibility with TTL and DTL
Applications:
* Voltage level comparison
* Window detectors
* Zero-crossing detectors
* Phase detectors
* Comparators in analog circuits
Package Options:
* DIP-8
* SOIC-8
* MSOP-8
Pin Configuration:
| Pin | Name | Description |
|—|—|—|
| 1 | +IN | Non-inverting input |
| 2 | -IN | Inverting input |
| 3 | OUT | Output |
| 4 | VCC | Positive power supply |
| 5 | GND | Ground |
| 6 | NC | No connection |
| 7 | NC | No connection |
| 8 | NC | No connection |
Electrical Characteristics:
| Parameter | Condition | Min | Typ | Max | Unit |
|—|—|—|—|—|—|
| Supply Voltage | | 2 | | 36 | V |
| Input Voltage Range | | -0.3 | | VCC+0.3 | V |
| Open-Loop Gain | | 100,000 | 200,000 | | V/V |
| Input Bias Current | | | 50 | | nA |
| Output Short Circuit Current | | | 20 | | mA |
| Power Consumption | | | 100 | | μA |
Operation:
The LM393 is a standard operational amplifier configured as a comparator. When the voltage at the non-inverting input (+) is greater than the voltage at the inverting input (-), the output is high (approximately VCC). Conversely, when the voltage at the inverting input is greater than the voltage at the non-inverting input, the output is low (approximately GND).
Applications Information:
* Reference Voltage: The reference voltage for the LM393 can be set using a resistor divider network or a Zener diode.
* Hysteresis: Hysteresis can be added to the comparator by connecting a positive feedback resistor between the output and the non-inverting input.
* Output Load: The output of the LM393 can drive TTL or DTL inputs directly. However, it is recommended to use a pull-up resistor or an external transistor buffer for higher current loads.
Design Considerations:
* Power Supply Decoupling: It is recommended to use a decoupling capacitor between the VCC and GND pins to suppress noise and ensure stability.
* Input Protection: The inputs of the LM393 are not protected against overvoltage. Therefore, it is important to limit the input voltage range to -0.3V to VCC+0.3V.
* Output Current: The output current of the LM393 is limited to 20mA. Ensure that the load impedance is compatible with the output current capability.
