High-voltage transmit/receive switches

rsdio writes:  These chips look highly flexible for interfacing between different voltage logic circuits MAX4936, MAX4937, MAX4938, MAX4939 Octal high-voltage transmit/receive switches Integrated T/R switches significantly reduce component count while reducing power Integrated solution reduces system component count, saving space and improving system reliability Consumes less system power, allowing design flexibility in ultra-portable applications Integrated […]

App note: SMBus-programmable battery chargers

rsdio writes:  SMBus is similar to I2C, and should therefore be easily connected to most PIC or AVR projects. Highly integrated, 850kHz/500kHz SMBus-programmable battery chargers: MAX17435/MAX17535, highly integrated SMBus™ battery chargers capable of operating at 850kHz and 500kHz, respectively. Unlike competitive solutions, MAX17435/MAX17436 allow the charge setting to be programmed via the SMBus interface, eliminating […]

25A 14V step-down regulator with integrated FETs

McZ writes in with an impressive step-down regulator: The TPS56221 is a high-efficiency synchronous switcher with integrated FETs, which achieves a power density of greater than 200W/in3 with greater than 90 percent efficiency at high loads. The easy-to-use SWIFT step-down regulator supports 25-A point-of-load designs for telecommunications, networking and other applications.

App note: Low-cost circuit converts clock to low-distortion sinewave

rsdio writes:  nothing beats a pure sine wave oscillator, except another pure sine wave oscillator at a similar frequency: This circuit derives a pure sinewave from a crystal-controlled clock source by using a ring counter to remove the highest-amplitude unwanted harmonics, and filtering the result with an 8th-order lowpass, switched-capacitor elliptic filter (MAX7400).

App note: developing embedded graphics applications with PIC® MCUs with integrated graphics controller

Microchip has a new application note for developers designing their first MCU graphics related application. It describes the definitions and terms relating to graphics applications, and discusses the theory, necessary decision factors, hardware considerations, available microcontrollers and development tools. This is a fairly comprehensive doc, starting out with the basics and moving quickly to complex […]

App note: Extend range of current-sense amplifiers

A current-sensor would be useful in a lab power supply. This app note is about chaining two current-sense chips to use at high voltages: Using a transistor as shown, you can double the allowed voltage limit on a current-sense amplifier by stacking two such amplifiers one upon the other. The voltage signal from the bottom […]

App note: High-voltage, programmable-gain current monitor

Another article that might help with bench power supply designs: This circuit monitors current flow at high voltage (48V and higher) using a standard 5V difference amplifier (MAX4198) referenced to ground. It also employs a digital potentiometer (MAX5402) for gain adjustment. Thanks rsdio!

App note: Linkwitz equalizer puts the bass in subwoofers

rsdio writes:  If anyone is building a subwoofer crossover, this is a great article! Nice use of opamps too. The linearity and high power-handling capability of modern low-frequency loudspeakers have made it easy to electronically extend the bass response. This extension is especially useful in second-order systems like a closed box, where cone excursions are […]

MAX31855 cold-junction compensated thermocouple-to-digital converter

Drone writes: Here is another MAXIM unobtainium installment The new MAX31855 is a rather nice cold-junction compensated thermocouple-to-digital converter. It takes the likes of the MAX6675 to the next level. This part is supposedly going to become available around the end of June 2011. From the product page: “The MAX31855 performs cold-junction compensation and digitizes […]

App note: Parallel LED drivers for maximum current

rsdio writes: This looks like a handy utilization of the basic bipolar transistor current mirror, based on the DMMT5401. For once, the key component is not a Maxim part, but Diodes Inc. ;-) Using a pair of matched transistors to translate a high-side current-sense signal down to a ground reference, this circuit lets you parallel […]

Designing PCBs for automotive applications

This application note gives PCB design tips for reducing EMI in automotive environments. A lot of the advise can be applied to any PCB layout. Electromagnetic interference (EMI) and electromagnetic compatibility (EMC) testing is an important part of design verification for serializer/deserializer (SerDes) devices in automotive applications. EMI and EMC must be considered early in […]

App Note: Versatility of CTMU

This Microchip application note explores the many uses for the Charge Time Measurement Unit (CTMU). CTMU is a flexible analog module that provides accurate differential time measurement between pulse sources, as well as asynchronous pulse generation. Together with other on-chip analog modules, the CTMU can be used to precisely measure time, measure capacitance, measure relative […]

Chip powers LED lamps in MR16 halogen bulb systems

This driver is used in LED replacement lamps for MR16 halogen bulb sockets. It’s compatible with common dimmers: The MAX16840, an LED driver that employs a proprietary architecture to ensure flicker-free, dimmable operation with electronic transformers and cut-angle dimmers. Maxim’s patent-pending approach enables the design of retrofit LED lamps that can replace halogen MR16s without […]

1.8V/3V sim card power supply with level translator

McZ found a sim card power supply with level translator: The TXS4555 is a complete Smart Identity Module (SIM) card solution for interfacing wireless baseband processors with a SIM card to store I/O for mobile handset applications. The device complies with ISO/IEC Smart-Card Interface requirements as well as GSM and 3G mobile standards. It includes […]

App note: DC voltage controls PWM dimming of high-brightness LEDs

An app note on a LED-driver circuit: This LED-driver circuit includes a hysteretic controller U1 (MAX16820), related power components, and a control circuit based on the quad op amp U2 (LMX324). U1 drives five HB LEDs from a 24V source, using only inductor L1, MOSFET Q1, and catch diode D1. Thanks rsdio!

LM0901a1411090451C polis operational amplifier

Akos tips us to the LM0901a1411090451C polis operational amplifier: The LM0901A1141090451C is a macropower, low performance, degraded circuit operational amplifier designed to have a no load power dissipation of less than 0.553W at Vs = ±1pV and less than 200W at Vs = ±2pV. Open loop gain is greater than 0.001k and input bias current […]

Using the EUSART

The term UART (Universal Asynchronous Receiver Transmitter) is the technical term for the good old serial port found on most MCUs. The term USART similarly refers to a serial port capable of handling both synchronous and asynchronous operation. Over the past few years, Microchip has been integrating an updated serial port into many of their […]