This is not really an app note, but more of a tutorial on DIY op-amp based linear regulators. The article describes the basics of op-amp regulator, and includes schematics and in-depth explanations of how the various circuits work. This article follows the history of a popular series of DIY linear regulators. Starting from initial concepts […]
Tag Archives: op-amp
App note: An applications guide for operational amplifiers
Here is a application guide from Texas Instruments is an overview of operational amplifier-related circuits, theory, and formulas. Inverting amplifiers, buffers, analog adders, filters, and many more are covered. The general utility of the operational amplifier is derived from the fact that it is intended for use in a feedback loop whose feedback properties determine […]
App note: Op-amp/comparator module for dsPIC
Some dsPIC33E and PIC24E microcontrollers have an comparator module that can function as an op-amp [PDF]. The module can be used as a simple non-inverting amplifier by adding two external resistors, no external op-amp chip needed. The output can be read internally by the ADC module, or routed externally to use in your circuit.
Simple USB DIY Li-ion battery charger circuit
arup shared his USB DIY Li-ion battery charger circuit in the project log forum. The circuit uses both op-amps of an LM358 to control the charging of a single cell lithium ion battery. Charging automatically stops when the battery is full, and it is possible to charge batteries that have gone below the undervoltage limit. Power […]
TS1001 low power, low voltage op-amp review
We have been experimenting with the Touchstone semi TS1001 ultra-low power, low voltage op-amp demo board, and the results are in. For our tests, the board inverting op-amp circuit was powered by a solar cell from a calculator with two 0.5v zener in series. The total supply was about 950mV, well below the operating range […]
Touchstone TS1001 op-amp demo board unboxing
Touchstone Semi sent a demo board for the record-breaking, low power, low voltage TS1001 op-amp. We covered their design competition earlier. The demo board has a complete support circuit so the parts are ready to evaluate. It’s populated with two TS1001 op-amps, in inverting and non-inverting configurations. Attention component manufacturers: this is how to sample […]
Touchstone Semi Coolest Op Amp design competition
Touchtone Semiconductor is a startup company whose products include an op amp known as the TS1001, which they say is the only such component to operate on 0.8 V and 0.6uA. They’ve announced a Coolest Op Amp design competition for developers who incorporate the TS1001 into their designs. See the Touchstone Semi’s website for a […]
Dangerous DSO part 4: Over simulated
Yesterday we covered the Dangerous DSO analog front end. This circuit divides our +/-10volt input to +/-0.5volts, and re-centers it between the 2volt and 3volt range the ADC can measure. Today we’ll simulate the circuit to get a better feel for how it works. Dangerous DSO is a new logic analyzer/oscilloscope design we’ve been using […]
Dangerous DSO part 3: Messing with the front-end
Yesterday we looked at how the Dangerous DSO analog to digital converter works, and it turns out to be a pain in the butt. It only measures a 1volt (1Vp-p) range between 2volts and 3volts. That’s not a very useful range for an oscilloscope, so we need an analog front-end that transforms the input signal […]