It is well known that a 555 timer in astable mode can be frequency modulated by applying a control voltage (CV) to pin 5. The schematic on the top of Figure 1 shows this classic 555 VCO. Modulating pin 5 has some severe drawbacks: The control ...
Modern high-speed RS-485 data links are pushing the envelope to the absolute breaking point with regards to data rate versus cable length. Applications include position encoders, traffic monitoring, seismic networks, and GPS transceivers. Data ...
The circuit uses a very inexpensive C-MOS IC that is connected to a small photodiode. Using a unique inductive feedback network, the circuit provides high sensitivity under high ambient light conditions. It is a great circuit when you want to ...
Recently, frequent and favorite contributor Nick Cornford gave us a cool and novel acoustic-interface design for a super sub-ohmmeter capable of audibly sniffing out defects in PWBs: “Tuneful track-tracing” ( Ref. 1 ). Figure 1’s ...
Frequent contributor R. Jayapal recently shared an interesting Design Idea (DI) for power supply control and sequencing in MCU-based applications that combine analog and digital circuitry: “Short push, long push for sequential operation of ...
A topic that has recently drawn a lot of interest (!) and no fewer than four separate design articles (!!) here in Design Ideas, is the conversion of 0 to 20 mA current sources into industrial standard 4 mA to 20 mA current loop signals. ...
Commercially available IR distance rangers typically handle a 3- to 30-in. detection distance. Many times, it is necessary to determine smaller distances. The circuit in Figure 1 is useful for measuring small distances to reflective surfaces. Its ...
High-resolution mixed-signal devices present an interesting challenge as you try to find the right voltage-reference design. Although no universal approach exists for these voltage-reference designs, the circuit in Figure 1 presents an interesting ...
An important figure of merit for all precision constant current sources is their active impedance. Which is to say, just how “constant” is their output held against changes in applied voltage? Frequent and expert Design Idea (DI) ...
The versatility of the venerable LMC555 CMOS analog timer is so well known it’s virtually a cliche, but sometimes it can still surprise us. The circuit in Figure 1 is an example. In it a single linear pot in a simple RC network sets the ...