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Safe Operating Areas For Peripheral Drivers - 09/30/99 EDN-Design Ideas / (added 6/06)

Safely Swap Scsi Disk Drives - Microchip Application Note Published 26-Aug-97   (app note added 2/06)

Saving And Restoring Status On Interrupt - National Semiconductor Application Note   (app note added 2/06)

SB-101: Digital Pbx Linecard And Terminal - National Semiconductor Application Note   (app note added 2/06)

SB-102: Isdn Terminals And Terminal Adapters - National Semiconductor Application Note   (app note added 2/06)

SB-103: Isdn Network Terminators And Repeaters - National Semiconductor Application Note   (app note added 2/06)

SB-108: Apple Macintosh Ethernet Add-In Card - National Semiconductor Application Note   (app note added 2/06)

SB-110: Ibm 3270/5250 Connectivity - National Semiconductor Application Note   (app note added 2/06)

SB-111: Mass Storage: Hard Disk - National Semiconductor Application Note   (app note added 2/06)

SB-113: Laser Beam Printer Lbp Controller Solution Card - National Semiconductor Application Note   (app note added 2/06)

SB-114: Monitor: VGA - National Semiconductor Application Note   (app note added 2/06)

SB-115: A Fddi: Ethernet Router - National Semiconductor Application Note   (app note added 2/06)

SB-116: Fddi: Adapter Card - National Semiconductor Application Note   (app note added 2/06)

SB-117: Pc87310 Super I/O - National Semiconductor Application Note   (app note added 2/06)

Scalable LaTCh Requires No Capacitors Or Clock - (electronic circuit added 4/05)

Scenix And Pic Programmer - Pericom Semiconductor App Note # 044 (app note added 02/05)

Schematic And Board Layout Recommendations For Pi7c7300 - Pericom Semiconductor App Note # 057 (app note added 02/05)

Schematic And Layout Guidelines For Pi7at04 - ….(electronic schematic added 06/09)

Schematic Of A Standard PC Joystick - (07/20/00 EDN-Design Ideas / (added 11/05)

Scheme Autodetects Baud Rate - 02/16/98 EDN-Design Ideas  / (added 2/06)    

Scheme Implements Multiple Output Ports  - 10/30/03 EDN Design Ideas  /  (added 1/05)  You can easily improve on a previous Design Idea to produce a slightly simpler resistor arrangement with better timing balance between switches, using a single resistor value (Reference 1, Figure 1). The use of a single resistor value, RS, in a series chain for the switch resistors gives the timing....

Scheme Improves On Low Cost Keyboard - ….(design added 06/09)

Sega 3d Glass Interfacing Circuits - (design circuit added 8/02)

Sega 3d Glass Interfacing Circuits #2 - Fairchild Application Notes / (app note added 6/06)

Selection Of Mosfets In switch Mode Dc-Dc Converters / Ab-8 - High fidelity external USB Soundcard / USB Headphones project that can be built for your PC or Mac. It is based on the latest PCM2706 IC which functions as a high quality, crystal clear 16-BIT Stereo DAC. It is a single chip digital-to-analog converter that offers two D/A output stereo channels, digital S/PDIF output and requires very few external components. PCM2706 includes integrated USB 1.0 & USB 2.0 compliant interface controller and it is conveniently powered directly from USB connection. PCM2706 is a USB plug-and-play device and does not require any driver installation under Windows XP and Mac OSX. ….(electronic schematic added 11/08)

Self-Powered Soundcard  - ….(design added 08/08)

Serial Cable For Casio Digital Cameras - 10/13/94 EDN Design Ideas /  (added 11/05)

Serial Controlled Postage Stamp Computer Governs Process - 03/28/96 EDN-Design Ideas / (added 11/05) 

Serial Controller Ic Interfaces With Adsp2100a - National Semiconductor Application Note   (app note added 2/06)

Serial Digital Video And Interface Rapidesigner Operation And Applications Guide - a simple, cheap device that can be connected to any serial port to control most components that have infrared remote controls, includes schematics for receiver and transmitter   (added 4/02)

Serial Infrared Remote Controller - (circuit schematic added 6/07)

Serial Interface And Bias Supply For Seiko-Epson G1216b Dot Graphics Display - Serial LCD/VFD Controller is a HD44870 based LCD/VFD controller via RS-232. The control command is compatible with Matrix-Orbital's LCD module. So, you can use any MO friendly software to control this baby such as LCDC. ….(design added 11/08)

Serial Lcd Controller - Connect an LCD to your microcontroller to make it easy to develop and debug your application. You can choose which PIC I/O pins you want to use for the interface, and any HD44780 compatible LCD can be controlled…..(design added 05/09)

Serial Lcd For Microcontrollers Using Only 3 Pins - (electronic circuit added 4/05)

Serial Midi Interface - (design circuit added 8/02)

Serial Port A/D Converter - 12bits, no power, cheap! (added 7/03)

Serial Port A/D  - This circuit is a simple 8-bit analogue to digital converter circuit which is connects to PC serial port. The circuit is based on TLC548 A/D-converter chip (might be hard to get nowadays, Texas Instruments makes this IC), which is an A/D-converter with serial output. The output of the TLC548 is not directly suitable for standard serial data reception…. (added 10/04)

Serial Port A/Dconverter - Control all your devices from the PC. This infrared remote control transmitter can be controlled from the PC serial port. It speaks different remote control formats, like the Philips RC-5 standard and can be tailored to other specific types....(electronic circuit added 7/03)

Serial Port Controller Infrared Transmitter Pic16f628 - 10/12/95 EDN-Design Ideas / (added 11/05) 

Serial Port Drives 12 Bitadc - This article shows how to use the PIC16F84 microcontroller with PicBasic to design a quick & effective, serially controlled, I/O-Expander.  Using PicBasic makes developing handy single-chip devices like this extremely simple….(added 08/08/08)

Serial Port I/O Expander - This is a simple I/O interface using an AVR microcontroller. The i/o pins are controlled by the AVR and can be used to drive LEDs, control RC servos, eTC. Using the attached relay circuit it can also be used to control relays. This schematics also provides a programming interface….(design added 06/09)

Serial Port I/O Interface - The PIC programmer project presented here is intended to be used by more experienced developers who already have access to a simple PIC programmer, because the programmer hardware is built around one 16F627(A) or 16F628(A) microcontroller that has to be preprogrammed with firmware. The presented solution uses PC's serial port for reliable communication between the programming software and 'intelligent' PIC programmer hardware. ….(circuit design added 11/08)

Serial Port Professional Pic Programmer - 12/09/99 EDN Design Ideas /  (added 11/05)

Serial Port Provides Interrupts For 8031µC - Microchip Application Note Published 26-Aug-97   (app note added 2/06)

Serial Port Routines Without Using The RTCc - (circuit / schematic design added 1/07)

Serial Port To Midi Synthesizer Interface Cable - Microchip Application Note Published 26-Aug-97   (app note added 2/06)

Serial Port Utilities Implementing Table Read And Table Write - ….(design added 06/09)

Serial To Ecp Interface - 08/01/96 EDN-Design Ideas  /  (added 2/06) 

Shared-Memory Interface Eliminates Arbitration - There are a few different ways of doing this but basically you have to make the heatsinks NOT live and you have to provide better cooling for the transistors. The heatsinks used in PSUs are generally soldered to the PCB via little metal tabs and current usually flows through them, ie they are live with voltage and act as part of the circuit. What you have to do is cut the tabs which takes the heatsinks out of the circuit and them use wire to replace them in part of the circuit. ….(circuit design added 11/08)

Silent Fanless Computer Power Supply - This circuit is a simple 8-bit analogue to digital converter circuit which is connects to PC serial port. The circuit is based on TLC548 A/D-converter chip (might be hard to get nowadays, Texas Instruments makes this IC), which is an A/D-converter with serial output. The output of the TLC548 is not directly suitable for standard serial data reception…. (added 10/04)

Simple Analog-To-Digital Converter - These are four different AVR programmers that can be controlled via standard ports of a PC.  (added 10/05)

Simple Avr Programmers - Microchip Application Note Published 16-Sep-02   (app note added 2/06)

Simple Can Node Using The Mcp2510 And Pic12c67x - (Design Ideas - EDN, 11/09/2006)  Greatest-of-three voltage detector drives indicators and external display. (electronic design idea added 9/2008) 

Simple Circuits Sort Out The Highest Voltage - DN1008  Design Notes (Linear Technology)  (app note added 1/06)

Simple Efficient All-In-One USB Power Management Ic Solution - (Design Ideas - EDN, 06/07/2007)  The low input-bias current of a voltage-follower op amp allows this simple fixture to measure the leakage current of capacitors and reverse-biased active devices. (electronic design idea added 9/2008) 

Simple Fixture Determines Leakage Of Capacitors And Semiconductor switches - If you are thinking about adding a USB interface between your project and a PC, read on. Implementing USB is now easier than you think. Eddy Insam will show you how. The USB (Universal Serial Bus) provides a new way of interfacing low and medium speed peripherals to personal computers. That old workhorse, the RS232 connector, is fast becoming obsolete, even becoming absent in newly purchased PCs. ….(electronic schematic added 11/08)

Simple Ft245 USB Oscilloscope For The PC - (electronic circuit added 4/05)

Simple Midi switcher - Sometimes when experimenting with different soundcards and MIDI interfaces it is useful to see if there is some data going in MIDI interface. This can be easily tested with this adapter, which converts the midi signals to visible light pulses. Just the circuit and plug it to the MIDI output of ... (added 4/05)

Simple Midi Tester - 05/26/94 EDN Design Ideas /  (added 11/05)

Simple Module Gives Voice To PC  - 09/28/95 EDN-Design Ideas / (added 11/05) 

Simple Monovibrator Uses Three Pld Pins - If you need to add simple data acquisition capabilities to your PC, then look no further than the Analog Interface Unit. The Analog Interface Unit (AIU) is a simple circuit that connects to a PC parallel port, and allows you to sample and output 8-bit analog signals under software control. Here are some of the features : * 8-bit ADC and DAC * Powered from the parallel port * 1Mohm input impedance. * Software selectable +/-1.25V or +/-2.5V input and output ranges. ….(design added 11/08)

Simple PC Data Acquisition Circuit - ….(design added 08/08)

Simple PC Thermometer - (electronic circuit added 11/05)

Simple Printer Emulator Adapter - (electronic circuit added 4/05)

Simple Rs-232 Serial Port Buffer Circuit - (electronic circuit added 4/05)

Simple Rs232c Level Converter Using Transistors - Here is an inexpensive way to get slow-moving analog data directly into a spreadsheet on your computer! A simple circuit connects to a serial port and a short Qbasic program gathers and saves 12 bit data to a file. A spreadsheet... (electronic design added 6/07)

Simple Serial Interface Schematic Was Missing A Ground. - National Semiconductor Application Note   (app note added 6/06)

Simple Technique Makes Low Cost PC Board Shields - This is a description of a very simple unit designed and constructed for use as a wireless data connection between two nearby computers. The error rate is excellent over short runs, and the transmission speed means that a useful PPP link can be established between the machines. Which are, of course, running Linux..... (added 4/05)

Simple Wireless Radio Data Link - ….(circuit design added 08/08)

Simplemouse SmarTCard Programmer Circuit - Aligent Application Note  (app note added 4/08)

Simplified PC Connections For Gpib Instruments - 06/24/2004  EDN-Design Ideas  Simulating the output-offset current of a current mirror is straightforward. You simply have to apply an input current, measure the output current, and calculate the difference. This output-offset current, however, is not equal to the input-offset current, especially when the circuit is not a 1-to-1 mirror.  (added 10/05)

Simulate Input Offset Current For Current Mirrors - 08/05/99 EDN-Design Ideas / (added 5/03) In many µC designs, nearly all the I/O pins are occupied. If only one I/O pin is available, the circuit in Figure 1 can help you implement a serial RS-232C interface. For many purposes, half-duplex operation using a software-driven RS-232C interface provides a good communications link. Many µCs have open-drain I/O pins,....

Single µC Pin Makes Half Duplex Rs 232c - 01/04/96 EDN-Design Ideas / (added 2/06)  The design in Figure 1 allows for a single board to support both an 8and a 16-bit bus width. The 8-bit Am186EM µC would use both SRAMs and have 0 Ohm resistors or jumpers connecting A17 and WHB to the SRAMs. The 16-bit Am188EM µC would ....

Single Board Supports Two Bus Widths - DN289  Design Notes (Linear Technology) (app note added 1/06)

Single Interface Chip Controls Two Smart Cards - DN29  Design Notes (Linear Technology) (app note added 6/06)

Single Supply Rs-232 Interface For Bipolar To D Converters - 10/22/98 EDN-Design Ideas  / (added 11/05)   

Single Wire Connects Microcontrollers  - 03/31/05 EDN Design Ideas  / (added 5/05)  Using this interface topology, you can reduce the number of keypad interface wires to just one and thus save critical microcontroller I/O ports.

Single Wire Keypad Interface Frees Microcontroller I/O Pins - National Semiconductor Application Note   (app note added 2/06)

Sio Input/Output Register Description - 04/10/99 EDN-Design Ideas / (added 6/06)  [Note:  File contains multiple circuits.  Scroll to find this one.]  You can now get both modules and carrier boards for the PC-MIP mezzanine format. MEN and SBS-Greenspring (now called SBS Technologies) developed the format as a smaller alternative to PMC ....

Small Mezzanine-Board Format Offers More I/O - ….(electronic schematic added 08/08)

Smart Card Programmer - Microchip Application Note Published 16-Aug-00   (app note added 2/06)

Smart Sensor Can Node Using The Mcp2510 And Pic16f876 - ….(design added 08/08)

SmartCard PC Emulator - (electronic design added 6/07)

SmartCard PC Serial Reader / Writer Phoenix - DN193  Design Notes (Linear Technology) (app note added 1/06)

Smbus Accelerator Improves Data Integrity - (Design Ideas - EDN, 10/12/2006)  Phase-shift network plus a few active components yields low-distortion output. (electronic design idea added 9/2008) 

Soft Limiter For Oscillator Circuits Uses Emitter-Degenerated Differential Pair - EE-162 SoftwareCode-Analog Device Application Notes  (app note added 6/06) 

Software Code Ee-162  - EE-236 Analog Devices Application Notes  (app note added 2/06)

Software Code Ee-236  - EE-247 Analog Devices Application Notes  (app note added 2/06)

Software Code Ee-247  - EE-248 Analog Devices Application Notes  (app note added 2/06)

Software Code Ee-248  - National Semiconductor Application Note   (app note added 6/06)

Software I2c Routine For The Cop8 - Microchip Application Note Published 26-Aug-97   (app note added 2/06)

Software Implementation Of Asynchronous Serial I/O - Microchip Application Note Published 26-Aug-97   (app note added 2/06)

Software Implementation Of I˛C Bus Master - 06/08/95 EDN-Design Ideas / (added 11/05)

Software Implements Digital Potentiometer - 12/06/01 EDN Design Ideas  /  (added 1/05)The program in Listing 1 uses a pseudo-RETI instruction to provide a five-priority-level interrupt system for the 8051P microcontroller. The interrupt-priority order, from high to low, is INT0 IT0 INT1 IT1 INTP. Before the pseudo-RETI instruction arrives in the IT0 or IT1 interrupt-......

Software Makes Full Use Of 8051's Interrupt System - 08/03/98 EDN-Design Ideas  / (added 2/06)

Software Pll Locks Vcxo To Reference  - 05/16/02 EDN Design Ideas  /  (added 1/05)  You can use the circuit in Figure 1 to allow the I2C or SMBus to control device resets in a system by using the PCA9554 I2 C I/O-port IC. Normally, a reset function takes an active-low signal. On power-up of the PCA9554, the IC sets all the I/O pins as inputs. The 4.7-kΩ pull-down ....

Software Reset Uses I˛C I/O Port - (07/03/97 EDN-Design Ideas / (added 11/05)  

Software Routine Minimizes Large Logic Tables - (07/18/96 EDN-Design Ideas / (added 11/05) 

Software Routine Stabilizes Hardware Register  - 09/25/03 EDN Design Ideas  /  (added 1/05)The subset-sum problem is one of the most frequently occurring NP (nondeterministic, polynomial-time)-complete) problems. It asks whether a subset of numbers in a set of positive integers adds up exactly to a given value. A relaxed version of the problem tries to identify a subset of numbers that adds up to ....

Software Snippet Provides Improved Subset Sum Algorithm - 12/04/97 EDN-Design Ideas / (added 11/05)  

Software Speeds 8051 Rs-232c Receiver  - (electronic circuit added 8/02)

Sound Blaster Microphone Preamplifier - The Sound Blaster 16 PCI and Sound Blaster 16 ISA do not have a very sensitive microphone input. This little one transistor amplifier is powered directly from the microphone jack on the sound card and has LOTS of gain. Just put a 100uF bypass capacitor in parallel with the diode to increase gain even more. Note that sound cards....(added 2/05)

Sound Blaster Preamp: Fixes That Well Known Problem And Needs No Batteries  - (application / block diagram added 6/07)

Sound Card - Previously, E-DSP visited the possibility of using your sound card as a signal/function generator. I was curious about the results, but did not have a Windows machine close by to test it. After some searching, I found a Linux alternative and was able to test the limitations of my Sound Blaster Live!...(project added 6/07)

Sound Card Based Signal Generators - This is an improved version of the audio interface commonly used to connect a computer soundcard to a transceiver's receive and transmit audio circuits. This kind of interface is used by computer programs that send and receive SSTV, RTTY, CW, PSK31 and various other digital modes entirely in software. Soundcard interfaces are not data controllers, TNCs, decoders....(added 4/05)

Sound Card Interface With Tone Keyer - Make a sound card is no more a complex issue. If you use great IC PCM2702 from BURR BROWN / Texas Instruments you can create a fully functional USB sound card. This sound card can be powered from USB port and has one stereo output. You don’t need to install any driver for Windows XP and Vista, because they are already inside. This is really plug and play. ….(design added 11/08)

Sound Card With Pcm2702 - (schematic / circuit (added (6/03)

Soundcard Joystick Port Problem Solver - (circuit / schematic design added 04/09)

Steam Sound - Many floppy drives and some subminiature printers contain bipolar stepping motors that draw very little current. The first circuit will drive small 5 volt steppers directly but you can switch to a 407)0 chip and add output transistors to drive heaftier loads at higher voltages. The circuit is not particularly susceptible to motor....(added 2/05)

Stepping Motor Driver: Minimalist Circuit Uses One Cmos Gate And Is Reversible  - Intersil Application Block Diagram  (app note added 2/06)

Storage Area Network San - (application / block diagram added 6/07)

Storage Cd - Fairchild Application Notes / (app note added 6/06)

Substituting The Rc5051 For The Rc5050 / Ab-10 - National Semiconductor Application Note   (app note added 2/06)

Summary Of Well Known Interface Standards - 04/09/98 EDN-Design Ideas  / (added 11/05)   

Supervisory Circuit Monitors Modem Connection  - Fairchild Application Notes / (app note added 6/06)

Suppressing Mosfet Gate Ringing In Converters: Selection Of A Gate Resistor / Ab-9 - This simple adapter can be used to convert Y/C video (S-video) to a composite video. This adapter is useful in cases where your video output device has only S-video output but your signal source accepts only composite video input. This circuit works with both PAL and NTSC video standards. (added 4/05)

S-Video To Composite Video Adapter - Pericom Semiconductor Application Brief # 010 (app note added 02/05)

switching Rgb Video Between Monitor And TV Using Pi5v330 - (diagram added 2/07)

System Level Design Considerations When Using I2c Serial Eeprom Devices - (design circuit added 8/02)