LM311 - Voltage Comparator

The LM111, LM211 and LM311 are voltage comparators that have input currents nearly a thousand times lower than devices like the LM106 or LM710. They are also designed to operate over a wider range of supply voltages: from standard ±15V op amp supplies down to the single 5V supply used for IC logic.

LM311 - Voltage Comparator



Both the inputs and the outputs of the LM111, LM211 or the LM311 can be isolated from system ground, and the output can drive loads referred to ground, the positive supply or the negative supply. Offset balancing and strobe capability are provided and outputs can be wire ORed.

• Operates from single 5V supply
• Input current: 150 nA max. over temperature
• Offset current: 20 nA max. over temperature
• Differential input voltage range: ±30V
• Power consumption: 135 mW at ±15V

Related Resources -

Voltage Comparator Information And Circuits

This page provides basic information about voltage comparator integrated circuits and is to act as reference material for other circuits. The circuits shown are based on the LM339 Quad Voltage Comparator chip or the LM393 Dual Voltage Comparator chip. These devices are functionally the same. The LM311 Voltage Comparator can be used for these applications as well but it also has a number of unique features.

Comparators and Schmitt Triggers

An LM311 in a comparator circuit is shown at the right, with the pin numbers for the connections. The open-collector output is at pin 7, and the ground for this transistor is at pin 1. It is shown pulled up to the logic voltage of +5 with a 1k resistor, which is typical. The output of the LM311 can sink 8 mA. A comparator's output is essentially binary, YES or NO.

EdSim51 - 8051 Simulator

A virtual 8051 is interfaced with virtual peripherals such as a keypad, motor, display, UART, etc. The student can write 8051 assembly code, step through the code and observe the effects each line has on the internal memory and the external peripherals.

EdSim51 - 8051 Simulator

The student can learn how to scan a keypad, multiplex 7-segment displays, control a motor and count its revolutions, etc.

A Note from the Developer - Jjames Rogers - ."While lecturing in electronics at IT Sligo, I searched the Internet for an 8051 simulator suitable for teaching but to no avail. I therefore decided to develop my own simulator for the basic 8051 with virtual peripherals attached to the four ports."

"After about a year's working on the project, on and off, the result was the EdSim51 simulator. I then put together a set of notes that are now the Beginner's Guide to the 8051on this website."

The Virtual Peripherals:

• Analogue-to-Digital Converter (ADC)
• Comparator, UART
• 4 Multiplexed 7-segment Displays
• 4 X 3 Keypad and 8 LEDs
• DC Motor and 8 Switches
• Digital-to-Analogue Converter (DAC) - displayed on oscilloscope

SG2525 - SG3525 - PWM SMPS Regulator Chip

SG2525 - SG3525 - PWM SMPS Regulator Chip. A second generation ic switch mode controller optimized for high frequency.

SG3525 - Voltage Mode PWM

The SG3525A pulse width modulator control circuit offers improved performance and lower external parts count when implemented for controlling all types of switching power supplies. The on-chip +5.1 V reference is trimmed to +/-1% and the error amplifier has an input common-mode voltage range that includes the reference voltage, thus eliminating the need for external divider resistors. Half Bridge, Push-Pull.



Specs

• 8.0 V to 35 V Operation
• 5.1 V +/- 1.0% Trimmed Reference
• 100 Hz to 400 kHz Oscillator Range
• Separate Oscillator Sync Pin
• Adjustable Deadtime Control
• Input Undervoltage Lockout
• Latching PWM to Prevent Multiple Pulses
• Pulse-by-Pulse Shutdown
• Dual Source/Sink Outputs: +/- 400 mA Peak

100kHz Half Bridge Convertor - SG3525

This is a SMPS Circuit improved over the Application Note in the book SGS Motion Control Application Manual. This worked well. It helps you learn more about High Frequency Power Supply Design.

SG3525 usage in SMPS 500W - It was used in Parallel for Electroplating with a central Load sharing control between modules.

ICM7217 Presettable Up-Down Counter

The ICM7217 is a four digit, presettable up/down counter with an onboard presettable register continuously compared to the counter. The ICM7217 is intended for use in hard-wired applications where thumbwheel switches are used for loading data, and simple SPDT switches are used for chip control.

ICM7217 Presettable Up-Down Counter

This circuit provides multiplexed 7 segment LED display outputs, with common anode or common cathode configurations available. Digit and segment drivers are provided to directly drive displays of up to 0.8 inch character height (common anode) at a 25% duty cycle.

The frequency of the onboard multiplex oscillator may be controlled with a single capacitor, or the oscillator may be allowed to free run. Leading zeros can be blanked. The data appearing at the 7 segment and BCD outputs is latched; the content of the counter is transferred into the latches under external control by means of the Store pin.

Multiplexed Presettable Timer with ICM7217

• Four Decade, Presettable Up-Down Counter with Parallel Zero Detect
• Settable Register with Contents Continuously Compared to Counter
• Directly Drives Multiplexed 7 Segment Common Anode or Common Cathode LED Displays
• On-Board Multiplex Scan Oscillator
• Schmitt Trigger On Count Input
• TTL Compatible BCD I/O Port, Carry/Borrow, Equal, and Zero Outputs
• Display Blank Control for Lower Power Operation; Quiescent Power Dissipation <5mW
• All Terminals Fully Protected Against Static Discharge
• Single 5V Supply Operation

Three Point Preset Counter

delabs Notes-

This is another Intersil Masterpiece in days when using uP was complex and uC was not available.A 8085 could be used but with many supporting chips and it consumed power. This was a CMOS innovation low on power and just one ASIC had the fexibility for many digital operations.A ThumbWheel and Display Interface completed a Gadget.

Linden H McClure Embedded System Design

Linden H McClure Embedded System Design

Embedded System Design -

Embedded System Design is focused at the fundamentals of embedded system design, and is meant to give students experience in both hardware and firmware.

Computer Solutions - Embedded Development Tools

ARM, PPC, Coldfire products, tutorials and a nice database of 8051 chips. Supplying Embedded Development Tool in UK and The EU.

Computer Solutions Ltd - Embedded Development Tools

Assemblers, Compilers and Simulators - cross development software available for most micros.


Portable Digital Oscilloscope DSO-2102

The DSO-2102 PC-Based Oscilloscopes connect to your desktop or laptop via the parallel port or USB port (optional). Both channels can operate at up to 100 Million Sa/s with a 32K sample buffer. The 2102M version includes a Spectrum Analyzer (FFT), Advanced triggering, Pass/Fail testing and displays many other useful characteristics of the data.

More at COMSOL

TCP/IP for 8 and 16 bit Embedded Engineers. - An introduction to the subject including descriptions of many of the most important protocols and which ones to use in particular situations with example Embedded Applications.

A series of Embedded Tutorials gives you a fast introduction to CPU families and new communications technologies.

MicroNet TCP/IP for 8 & 16 bit Micros now with Wireless Ethernet 802.11b support.

Computer Solutions Ltd
1a New Haw Road, Addlestone, Surrey KT15 2BZ, England

Robust Electronic Design - John R Barnes

Robust Electronic Design

"As an engineer, I am always working on new things. So I am going to make some mistakes. But I find it very embarrassing to have to redo something because of a mistake that I could and *should* have avoided. ....."

John R. Barnes KS4GL

"My first book, Electronic System Design: Interference and Noise Control Techniques, concentrated on designing electronic equipment to work."

Industrial Standards Index

EMC/EMI/ESD standards for residential/ commercial/ light-industry generic devices

Full Standards Index

(EMC), electromagnetic interference (EMI), and electrostatic discharge (ESD) standards for information technology equipment (ITE) and related (generic) equipment.

Robust Electronic Design, Inc.