Use a Trick to Count Scope Events:  01/21/99 EDN-Design Ideas  / (added 11/05)  One advantage digital storage oscilloscopes (DSOs) have over analog scopes is trace persistence. You can easily see infrequent waveform features using a scope in infinite-persistence mode. However, the frequency of these features relative to that of a "normal" signal can sometimes be less than obvious. You may wonder, does that glitch appear 10% or only 1% of the time? And how often does that short clock cycle occur? When you take trace noise into account, even a color-gradded display does not directly or accurately give the information. A histogram is the most accurate way to give the information, but it requires time and expertise. The following hint provides a quick way to determine, using a DSO, how often each of two waveforms occurs....

Use of the LMV112 to Reduce Reference Clock Interaction in Handheld Device:  National Semiconductor Application Note   (app note added 2/06)

Use time domain analysis of Zobel network:  06/27/02 EDN Design Ideas  /  (added 8/03  A Zobel network is useful in making a reactive load appear as a pure resistance to a driving source prone to stability problems (Reference 1). A typical situation is an audio power amplifier driving a loudspeaker, modeled at first approximation as an inductance and a series resistor (Figure 1a). The addition of a series R2C network in parallel with the series R1L network forms a Zobel network ......

Using Pericom's PI6C10x Pentium II/Celeron 100 MHz Clock in Place of W48S111-14:  Pericom Semiconductor Application Note # 010 (app note added 02/05)

Using the ADXL202 in Pedometer and Personal Navigation Applications:  AN-602 Analog Devices Application Notes  (app note added 6/06)

Using the LM555 Timer with Photocell Detectors:  (schematic added 8/03)

Using the Power vs Time Curve:  MicroNote 104 from Microsem Guides the reader in determining peak pulse power and peak pulse current for pulse widths of different values than those specified for a given device. (app note added 6/06)

Variable timer:  (schematic added 8/03)

VCXO makes inexpensive dual clock reference:  11/27/03 EDN Design Ideas  /  (added 1/05)  This Design Idea describes an inexpensive circuit to generate two extremely high-quality, crystal-clock-reference-signals, one of which is a PWM-controlled VCXO (voltage-controlled crystal oscillator) clock signal (Figure 1). The design also includes circuitry to statically switch and hold the VCXO at its nominal fixed frequency of operation (equivalent to 50% PWM) without requiring any external......

Versatile Timer Operates from Microseconds to Hours:  National Semiconductor Application Note 24 Feb1999 (app note added 4/02)

Video clock superimposer using PIC16C711:  (electronic circuit added 04/05)

Video Clock Superimposer:  (schematic added 8/03)

Watchdog Circuit Protects Against Loss of Battery Charger's Control Signals:  07)/21/05 EDN Design Ideas  / (added 10/05)  Hardware circuit keeps software-based charging within limits.

Watchdog Circuit uses AC Triggering:  08/16/01 EDN Design Ideas  /  (added 1/05)  A dc-triggered reset of a watchdog circuit is prone to failure. If the watchdog program hangs up, then the reset signal becomes activated continuously, and the microprocessor has no way to escape the situation. We found that a simple solution uses an ac trigger to reset the watchdog circuit (Figure 1)....

Watchdog Circuit uses Leftover Gates:  08/01/96 EDN-Design Ideas / (added 3/03)  

Watchdog Time Out is Independent of Reset:  09/01/95 EDN-Design Ideas / (added 3/03)  

Watchdog Timer Allows Entry to Test Mode:  07)/19/01 EDN Design Ideas  /  (added 1/05)  Manuals for microprocessor-based devices often include instructions for entering a "secret mode" in which you can test or reset the device. These instructions typically ask you to depress and hold one or two switches for a minimum time interval. You can adopt several measures to avoid accidentally triggering the test mode: Depress two keys, hold both keys simultaneously and continuously through......

Watchdog Timer Assumes Varied Roles:  02/01/01 EDN-Design Ideas / (added 05/03)

Watchdog Timer Reboots PCs:  06/05/97 EDN-Design Ideas / (added 3/03)  

Watchdog-reset catcher aids embedded-system debugging :  11/19/98 EDN-Design Ideas  / (added 11/05)   

WatchMan Watcher:  (electronic Circuit / Schematic added 10/04)

Wide Range Timer:  National Semiconductor Application Notes,28 Jun1996 / (app note added 4/02)

Zero-Delay Clock Buffer Layout and Schematic Guidelines PI6C2502:  Pericom Semiconductor Application Note # 050 (app note added 02/05)