PAL Controls Simple Dual Port Memory:  04/27/95 EDN-Design Ideas / (added 6/06)

Parallel Port Controls Arbitrary Waveform Generator:  06/13/02 EDN Design Ideas  /  (added 1/05)  You can use the parallel port of your PC and a few additional components to generate a powerful, easy-to-use arbitrary-waveform generator. By using a Visual Basic program with the circuit in Figure 1, you can generate any waveform (for example, sinusoid, triangle, amplitudeor frequency-modulated, or exponential decay) by simply entering its characteristic equation....

Parallel Port Servo Controller:  (electronic circuit added 4/05)

PC Based Lighting Control:  short pointer to each of the available commercial PC based lighting console systems (added 6/06)

PC Controlled Voltage or Current Source:  Fair Waring, site contains annoying popups.  This project was begun as a means to charge and cycle NiCad batteries but has become a versatile tool for experiments requiring either a controlled voltage up to +30V and/or a current of +/2.5 Amps. (added 6/06)

PC Controls Light Dimmer:  08/19/99 EDN-Design Ideas / (added 6/06) Circuit design idea from EDN Magazine to control one light dimming from PC

PC Infrared Remote Control #1:  (circuit / schematic design added 6/06)

PC Interface for Point Controller:  (electronic circuit added 4/05)

PC IR Remote Control Hardware:  (electronic circuit added 4/05)

PC IR Remote Control:  (circuit / schematic design added 6/06)

PC Securely Controls Relay:  11/23/95 EDN-Design Ideas / (added 6/06) 

PC Speaker Volume Control Circuit #2:  (circuit / schematic design added 6/06)

PC Speaker Volume Control Circuit:  (circuit / schematic design added 6/06)

PC-Based DC Motor Speed Controller:  (electronic circuit added 4/05)

Peltier Element Controls Itself:  10/27/94 EDN-Design Ideas / (added 3/03) Peltier elements, or semiconductor heat pumps, combined with heat sinks are a designer's choice when controlled low temperature is required for CCDs and high-density ICs. These devices are suitable for device temperature cycling in reliability tests and for regular cooling. Because mounting inexpensive temperature sensors directly onto the controlled temperature surface isn't easy, a simple circuit (Fig 1b) provides the control. The circuit is successful because the Peltier element is a reciprocal device....   

Phase Controlled Lighting System:  This project was developed to provide some pleasant room lighting as the author was fed up with inflexible standard incandescent light bulbs used in most rooms. Specifically it details the use of five Low Voltage Lamp units as up-lighters placed around a room. Each lamp can be turned on/off individually and all lamps can be dimmed from full brightness down to zero brightness. Figure 1 shows one of the lamps mounted to a wall. (added 6/06)

PIC Based Motor Controller:  (circuit / schematic added 2/03)

PIC16c505 IR/Wireless Remote Control:  (electronic circuit added 7/03)

PIC16F84 Miniature Real Time Controller:  (circuit / schematic design added 6/06)

PIC16F84 RF remote Controller:  (circuit / schematic design added 6/06)

PIC16F84 Stepper Motor Controller:  (circuit / schematic design added 6/06)

PIC16F873 Light Controller:  (circuit / schematic design added 6/06)

PLL Implements FPGA Based SDRAM Controller :  05/21/98 EDN-Design Ideas / (added 6/06)  As FPGA capabilities increase and time to market decreases, FPGAs gain more acceptance for implementing both data and control paths. Thus, they find wide use as controllers and datapath glue logic for fast-page DRAMs. Synchronous DRAMs (SDRAMs), whose control signals use a clock input as reference, are a natural target for FPGA-based controllers. SDRAMs operate at frequencies of 100 MHz and higher (in contrast with fast-page DRAMs, for which a 60-MHz memory-system clock was considered high). Figure 1 shows a way to implement FPGA-based SDRAM controllers. Figure 2 shows the timing for a Xilinx XC4010E-2 device. You can apply the method to FPGAs from other vendors, as well as to high-frequency systems other than SDRAMs.... 

PLL-based converter controls light source :  07/02/98 EDN-Design Ideas  / (added 6/06)   Using the circuit in Figure 1, you can digitally control the light intensity of a lamp. The control loop is based on a PLL, in which the VCO comprises a light-to-frequency converter (TSL220) coupled to a light source that derives its drive from a switching regulator (L4970A). The output of the phase/frequency comparator (4046) serves as the control voltage for the switching regulator. The control voltage is proportional to the frequency error between the reference frequency (fREF) and the signal frequency (fIN) coming from the light-to-frequency converter. Changing the reference frequency regulates the voltage supplied to the lamp to force the output of the TSL220 to lock to fREF. The two resistors at the output of the 4046 provide an attenuation of 1000 to guarantee the loop stability....

Position detectors provide motor control logic:  05/24/01 EDN-Design Ideas / (added 6/06)

Power Chopper 1:  (Schematic added 10/06)

Power Output Stage Automatic Bias System Control IC (LT1166):  DN126  Design Notes (Linear Technology) (app note added 1/06)

Power Source is Insensitive to Load Changes:  04/04/02 EDN Design Ideas  /  (added 1/05)  For the heating and cooling elements common in industrial systems, resistance is not a fixed quantity. These elements include such devices as positive-temperature-coefficient heaters and thermoelectric coolers. Their resistance can change more than 100% during operation, and the result is a change in power dissipation for elements receiving drive from a fixed voltage or current source. ...

Precision Attenuator with Digital Control:  (circuit / schematic design added 6/06)

Precision Digital AC Power Controller:  (electronic Circuit / Schematic added 10/04)

Printer Port Controls Video Multiplexer:  08/01/96 EDN-Design Ideas  /  (added 6/06)

Processor Controls Watchdog Circuit:  01/18/96 EDN-Design Ideas / (added 6/06) 

Processor's PWM Output Controls Lcd/LED Driver:  05/27/04 EDN Design Ideas  /  (added 1/05)  The PWM (pulse-width-modulation) output available from many microprocessors is based on an internal 8or 16-bit counter and features a programmable duty cycle. It is suitable for adjusting the output of an LCD driver, a negative-voltage LCD driver, or a current-controlled LED driver. cost alternative that provides not only a 4to 20-mA output,

Programming supeR10 external bus controller registers:  AN1980  (app note added 6/06)

Programming the Automatic Fan Speed Control Loop:  AN-613 Analog Devices Application Note   (app note added 2/06)

Proportional Radio Remote Control:  (electronic circuit added 4/05)

Provide 4  to 20 Mpwm Control:  09/01/98 EDN-Design Ideas / (added 5/02)   -Are useful when you use4to20-mA current-loop signals to control a PWM signal

Pulse Width Modulation DC Motor Control:  controls the motor speed by driving the motor with short pulses (added 4/05)

Pushbutton Switch Controls Power Supply and µC:  09/25/97 EDN-Design Ideas / (added 3/03)  Switching handheld units on and off with a pushbutton switch is a desirable feature. Thus, switching-regulator/ controller ICs for battery-powered applications provide a logic input to switch the device to a shutdown mode. This type of shutdown pin can require additional components and logic gates to implement the pushbutton interface. However, a simple circuit can implement an on/off function with no external logic (Figure 1). The circuit is based on IC1's step-down controller, which provides the toggle on/off function internally with a SET/RESET latch. Momentarily grounding the ON pin sets the latch and turns on the regulator; momentarily grounding the LBI/OFF pin resets the latch and turns off the regulator....  

PWM Controller:  555 Timer based PWM motor control project for electric fan or other DC motor (added 6/06)

PWM DC motor Control with SG3525:  (circuit / schematic design added 6/06)

PWM DC Motor Speed Control:  (circuit / schematic design added 6/06)

PWM motor Controller:  (circuit / schematic design added 6/06)

PWM Motor/Light Controller Variants:  (electronic circuit added 4/05)

PWM Motor/Light Controller:  (electronic circuit added 4/05)

PWM Speed Control:  includes theory and some example circuits (added 6/06)

Quartz Crystal Based Remote Thermometer Features Direct Celsius Readout:  03/17/05 EDN Design Ideas  / (added 5/05)  Although quartz crystals have served as temperature sensors, designers haven't taken advantage of the technology because few manufacturers offer the sensors as standard products (references 1 and 2). In contrast to conventional resistanceor semiconductor-based sensors, a quartz-based sensor provides inherently digital-signal conditioning, good stability, and a direct digital ou...