LM2903D R2G Detailed explanation of pin function specifications and circuit principle instructions

The LM2903DR2G is part of the ON Semiconductor product family. It is a dual comparator with an open collector output, typically used for signal comparison in various electronic circuits. The following information is a detailed breakdown of the component specifications, pinout, and common usage instructions.

Package and Pinout Information

Package Type: SOIC-8 (Small Outline Integrated Circuit - 8 pins) Total Pins: 8 pins in total

Pin Function List for LM2903DR 2G

Here is a detailed explanation of each pin and its function:

Pin Number Pin Name Function Description 1 Out A Output of the first comparator (A). Open collector, requires external pull-up resistor. 2 Inverting Input A Inverting input of the first comparator (A). The voltage applied here is compared with the non-inverting input. 3 Non-Inverting Input A Non-inverting input of the first comparator (A). The voltage applied here is compared with the inverting input. 4 V− Negative supply voltage (ground). The LM2903 is a dual comparator that operates with a single supply or dual supplies. 5 Non-Inverting Input B Non-inverting input of the second comparator (B). The voltage applied here is compared with the inverting input. 6 Inverting Input B Inverting input of the second comparator (B). The voltage applied here is compared with the non-inverting input. 7 Out B Output of the second comparator (B). Open collector, requires external pull-up resistor. 8 V+ Positive supply voltage. This is typically connected to the voltage source Power ing the comparator circuit.

Application and Circuit Principles

The LM2903 is designed to function as a low-power, dual comparator. It uses open collector outputs, meaning that an external pull-up resistor is required for proper operation of the output stages. The primary application is in comparison circuits, where it compares two voltages and outputs a high or low signal accordingly.

Basic Circuit: Power Supply: Connect V+ to the positive supply voltage (typically +5V or +15V depending on your application) and V− to ground (0V). Input Signals: The comparator compares two voltages—one connected to the inverting input (pin 2 or pin 6) and the other to the non-inverting input (pin 3 or pin 5). Output: The output (pin 1 or pin 7) will be low when the voltage on the inverting input is higher than the voltage on the non-inverting input. It will be high (pulled up via a resistor) when the non-inverting input voltage exceeds the inverting input voltage.

FAQ Section for LM2903DR2G

Here are the 20 most frequently asked questions about the LM2903DR2G:

Q: What is the supply voltage range for the LM2903DR2G? A: The supply voltage range for the LM2903DR2G is from 2V to 36V for a single supply or ±1V to ±18V for dual supplies.

Q: What is the typical response time of the LM2903DR2G? A: The response time (propagation delay) is typically 200ns.

Q: What is the purpose of the pull-up resistor on the output pins? A: The pull-up resistor is required because the output is an open collector type, meaning it can only pull the output low. The resistor pulls the output high when the transistor is off.

Q: Can the LM2903DR2G be used in a single supply configuration? A: Yes, the LM2903DR2G can operate with a single supply voltage.

Q: What is the maximum output sink current of the LM2903DR2G? A: The maximum output sink current is 20mA.

Q: How should the inputs be connected for the LM2903DR2G to function correctly? A: The non-inverting and inverting inputs should be connected to the voltages that you want to compare. The non-inverting input will trigger a high output if its voltage exceeds the voltage on the inverting input.

Q: Can the LM2903DR2G be used in high-speed applications? A: While the LM2903DR2G has a typical response time of 200ns, it is not suitable for ultra-high-speed applications compared to other comparators designed for that purpose.

Q: Is the LM2903DR2G temperature-sensitive? A: Yes, the LM2903DR2G has a specified operating temperature range of -40°C to +125°C.

Q: What is the typical quiescent current of the LM2903DR2G? A: The typical quiescent current is 0.35mA per comparator.

Q: Can I use the LM2903DR2G in a voltage level shifting application? A: Yes, the LM2903DR2G can be used for level shifting if the comparator is set up correctly with appropriate input voltages.

Q: How many comparators are there in the LM2903DR2G? A: The LM2903DR2G contains two comparators (dual comparator IC).

Q: What is the function of the open collector output? A: The open collector output allows the comparator to sink current but not source it, which is useful in various applications requiring a pull-up resistor.

Q: What are the available package types for the LM2903DR2G? A: The LM2903DR2G is available in the SOIC-8 package.

Q: Can the LM2903DR2G operate at low voltages? A: Yes, the LM2903DR2G can operate with a supply voltage as low as 2V.

Q: How does the LM2903DR2G behave with inputs that are equal? A: If the voltages at the non-inverting and inverting inputs are equal, the output will remain in an indeterminate state.

Q: Can I use the LM2903DR2G in automotive applications? A: Yes, the LM2903DR2G is rated for use in automotive applications as it has an extended operating temperature range.

Q: What is the power consumption of the LM2903DR2G? A: The LM2903DR2G has low power consumption with a typical supply current of 0.35mA per comparator.

Q: What are the typical applications for the LM2903DR2G? A: The LM2903DR2G is typically used in zero-crossing detectors, waveform generators, and overvoltage or undervoltage detectors.

Q: Is the LM2903DR2G a single comparator or dual comparator? A: The LM2903DR2G is a dual comparator IC.

Q: How do I choose the pull-up resistor for the output? A: The value of the pull-up resistor depends on the operating voltage and desired output current; typically, a resistor between 1kΩ and 10kΩ is used.

This information is aimed at providing a comprehensive understanding of the LM2903DR2G's pinout, function, and common queries about its operation.