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While working on various data acquisition projects, I realized that making my applications aware of the date would be a necessity.  PCs by definition are already date aware, but I am working on small stand-alone data acq projects without a real time clock.  Enter the Maxim (Dallas) DS1307 64 x 8, Serial, I2C Real-Time Clock.  Maxim has this to say about their chip…

The DS1307 serial real-time clock (RTC) is a low-power, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV SRAM. Address and data are transferred serially through an I2C, bidirectional bus.   The lock/calendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with AM/PM indicator. The DS1307 has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply. Timekeeping operation continues while the part operates from the backup supply.

So couple this chip with a 3V lithium coin cell battery, a crystal and a couple of resistors, and your next microcontroller project will be date aware.

COST: $3.74 USD (Digikey)

* all graphics copyright Maxim Integrated Products

Just a simple “cylon” or “knight rider” style light chaser this time around.  I whipped this up in about an hour, as an exercise in “CharliePlexing“, a method whereby LED connections to a microcontroller are greatly reduced.

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Prototyping boards are usually fscking expensive, $20 – $30 for a good Vero board.  The folks at ProtoStack have reasonably large, reasonably priced protoboards for $8.40.  Check em out.

Finally!  An effective means to prototype and interface to the Arduino Duemilanove without chasing it around the table, pulling it down by the USB or ethernet, or killing the solder joints trying to make positive connections.  I made up the following test and development bed.  More after the jump…

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This week’s Chip of the Week is the STMicroelectronics TDA2050, a 32W single channel “Hi-Fi” Audio Amplifier. This article also marks my first attempts at ripping graphics from datasheets.

ST has this to say about their chip…

The TDA 2050 is a monolithic integrated circuit in Pentawatt package, intended for use as an audio class AB audio amplifier. Thanks to its high power capability the TDA2050 is able to provide up to 35W true rms power into 4 ohm load @ THD = 10%, VS = ±18V, f = 1KHz and up to 32W into 8ohm load @ THD = 10%, VS = ±22V, f = 1KHz. Moreover, the TDA 2050 delivers typically 50W music power into 4 ohm load over 1 sec at VS=22.5V, f = 1KHz.

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