SPI Interface Big 7-Seg LED  Big display for general purpose usage, the interfacing is SPI serial interface, requires only 3-wires.  Multiple digit can easily be made.  DXF files single side PCB.   __ Designed by Wichit Sirichote

SPI2CF, a fast & efficient WLAN interface for the AVR The page is about equipping an Atmel AVR microcontroller based system with a Prism WLAN interface.  This document is intended for people that already have experiences with the AVR microcontrollers and teaches them how to add a cheap but flexible WLAN interface to your AVR projects. __ Designed by Till Harbaum <Till @ Harbaum.org>

Splitting & arbiting a bidirectional serial bus EDN-Design Ideas 03/18/2016    Serial buses like I2C are wIdeaspread.  This Design Idea demonstrates ways of splitting each bidirectional line into two unidirectional ones – and Design by Jeff Anderson

Stepper Motor Interface M1 is a stepper taken from an old disk drive.  There are five pins, i.  e.  , common, coil 1, 2, 3 and 4.  Resistance measured between common pin and each coil is about 75 Ohms.  Driving current for each coil is then needed about 60mA at +5V supply.  A darlington transistor array, ULN2003 is used to increase driving capacity of the 2051 chip __ Designed by Wichit Sirichote

Storage Oscilloscope Adapter Yes, it's finally here !.  The DSOA Mk3 has been a long time coming (many years in fact) , but it was finally published in the October/November 98 issues of EA.  EA October 98 issue cover shot of DSOA Mk3 Here are the basic specs.  

Student DC Power Supply Build a simple DC supply having three output terminals: regulated +5VDC, unregulated +10VDC and 7.5VAC.  The supply is suitable for microcontroller experimenting.   __ Designed by Wichit Sirichote

Sun Type 5 keyboard on the PC Many people have dreamed of having their Sun Type 5 keyboard attached to their PC.  Now with this adapter, it is finally possible.  Because the standard Sun keyboards use TTL RS232 at 1200 bps to talk to the Suns, it's relatively easy to make them talk to any non-Sun computer by converting this to true RS232.  However PC's don't understand keyboards hooked up to serial ports without special drivers.  While such drivers do exist you will still need to keep a PC keyboard about if you want to change the BIOS setup etc __ Designed by Jonathan A. Buzzard

Sunvisor-Integrated GPS navigator We decided not to get the built-in GPS navigation for the Mini Cooper because it is awfully expensive and from the reviews, it looks like it isn't very good.  I commited myself to install a TomTom navigator in the car, and it should be better, cheaper, and should look like a factory option.   __ Designed by Roberto Barrios EB4EQA

Supervise & Power-Sequence an SOC 05/13/10 EDN-Design Ideas Microprocessors, microcontrollers, and SOCs(systems on chips) often need a reset pulse to initialize properly.  Many of these devices also use separate I/O- and core-voltage supplies.  When you use multiple supplies, you must turn them on in a specific sequence to prevent the circuits from ending up in an unknown state or burning out due to unexpected current paths.  You should also monitor the voltages to ensure that the device does not come out of reset until both voltages settle to levels within the operating- voltage range.    Design by Eric Schlaepfer, Maxim Integrated Products, Sunnyvale, CA

Supervisory Monitors-modem connection 04/09/98 EDN-Design Ideas (Scroll to find this circuit) In telemetry or security applications in which a modem connection automatically establishes itself between two systems, a failure in one of the systems can interrupt the data exchange while the connection remains established until someone physically breaks the line or restarts the failed system.  This situation Design by J Basilio Simies and Jorge Landeck, Instrumentation Center of the University of Coimbra, Coimbra, Portugal

Supply 2A Pulses for GSM Transmission from 500mA USB or PCMCIA Ports DN307) Design Notes__ Linear Technology/Analog Devices

Supply Derives 5 & 3.3V from USB port 20-Dec-01 EDN-Design Ideas The circuit in Figure 1 derives its power from a USB port and produces 5 and 3.3V supply rails for portable devices, such as digital cameras, MP3 players, and PDAs.  The circuit allows the port to maintain communications while, for example, charging a lithium-ion battery.  IC2 boosts the battery voltage, VBATT, to 5V, and IC3 buck-regulates that 5V output down to 3 Design by Chad Olson, Maxim Integrated Products, Sunnyvale, CA

S-video to composite video adapter 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.   __ Designed by Tomi Engdahl

Switch Debouncer This circuit will remove the transient spikes and contact bounces from a non-latching push button switch.   __ Designed by Andy Collison

SWTP PR-40 Printer Interface Schematics The above was the most commonly used schematic for connecting a printer.  It allowed the user to switch between two outputs: to the video monitor, and to both the video monitor and the printer.  The below schematics functions as the prevous one, but adds a third switch setting for printing without sending output to the video monitor.  This increased the data output speed to the printer. __ Designed by Tom Owad

Synchronizing Controller Detects baud rate 03/02/98 EDN-Design Ideas NOTE :  File contains many circuits, please scroll to find this one.  A simple and inexpensive implementation using an eight-pin 12C508 controller(Microchip Technology, Chandler, AZ] provIdeas both bit-rate detection and a synchronous, appended-clock output from an asynchronous input-data stream(Figure 1a].    Design by William Grill, Riverhead Systems, Littleton, CO