Post Created date
PD0, PD1 Output Not Working
Thanks for the pointers guys. I'm a career RF and analog IC guy. I've got a product to deliver so I'm serious about learning pretty much every intricacy about the AVR MCUs and...
Thursday, 15 October 2009 - 00:06
PD0, PD1 Output Not Working
Guess who's the noob? I downloaded Eagle so I could view the schematic and PD0/PD1 are connected through a 1k resistor to the FT232 UART-USB bridge. So the UART must be enabled...
Monday, 12 October 2009 - 00:02
PD0, PD1 Output Not Working
Sorry, I've got an ATMega168 Arduino (actually a Seeeduino). I don't have a true schematic for the board but the pin is directly wired to a header that I have my logic analyzer...
Sunday, 11 October 2009 - 19:34
Low Current LCD Backlight
Thanks for the comments guys. I also just noticed that the backlight current was a lot different based on LED color. I was also surprised to see how much difference there was...
Friday, 25 September 2009 - 10:42
Li-ion BQ2057C charger, help!
Just back from a trip to Rome on business without internet access. Now I"m getting my fix! djoshi wrote: So for Vin 5V 1A that is (5-4.63)*1A=0.37W. So 0.37*50C/W=18.5C, would...
Friday, 25 September 2009 - 10:18
Li-ion BQ2057C charger, help!
Sorry, my 5V comment was confusing. You typically route the battery voltage around to other voltage regulators, ICs, etc. I assumed 3.0V to 5.0V as the voltage range for that main...
Saturday, 19 September 2009 - 14:17
Li-ion BQ2057C charger, help!
R2 is just a pull-up for the OC output on CC, the circuit isn't sensitive to its value. It sounds like it's operating correctly to me. For Li+ power supply designs I assume 5.0V...
Saturday, 19 September 2009 - 12:53
Measure AVR temp by checking RC osc freq
I wonder about that. I was thinking it would be fairly consistent. The internal R and C should have pretty consistent temperature coefficients, right? So to first order I would...
Saturday, 19 September 2009 - 03:14
Low Current LCD Backlight
Thanks for the comments. That's a good point on the voltage vs. current mode sourcing. I thought all LCD modules had an on-board resistor to set current for a given supply voltage...
Saturday, 19 September 2009 - 00:17
Interfacing Current Shunt
Check your solution against the tolerance you need. Parts like the INA family are trimmed on-chip in production to give extremely high common mode rejection. This just means you...
Saturday, 19 September 2009 - 00:02
Microntroller or dedicated chip for low battery indicator?
For future reference, in case you want to monitor without the MCU and need a really low current setup. Alkalines discharge at a few percent per year, say 2%, with a capacity of...
Friday, 18 September 2009 - 23:55
5V 5mA, best option for power? Power regulator info?
True, you can just run an output as an oscillator, use 2 diodes and 2 caps and you have a boosted output. The only problem I see in this application is that your Li+ batt voltage...
Friday, 18 September 2009 - 12:15

Pages