Post Created date
Driving a bunch of LED's. const voltage or const current
You are talking about the Catalyst series. Beware that you will need to do the PWM yourself by clocking it in constantly. These chips do not have a per LED enable/disable pin that...
Friday, 12 August 2011 - 02:44
Power harvesting cap
High current and high voltage charging spikes on a normal battery chemistry, as far as I know, will ALWAYS adversely affect the battery lifetime. That said: Step1: Use solid...
Friday, 12 August 2011 - 02:28
Measuting LED temperature
National has a very extensive range of sensors. LM92 is still in my stock as it works great over a large temperature range, but they also make the I2C devices in even smaller...
Friday, 12 August 2011 - 02:16
Zero crossing detection for TRIAC control
Loaded transformers are well known for their unreliability in keeping the signal neat. If you don't want to go into difficult calculations and long winded explanations of phase...
Friday, 12 August 2011 - 02:06
Virtual Com Port with two USB-headers
Well... okay then. But wouldn't you need to make a different PCB and inherently another package for the USB included final release anyway? I haven't met customers yet that needed...
Tuesday, 9 August 2011 - 13:28
which motor should i use for making a line follower robot ?
I'm tempted to mention the First Lego League here... Hey! I did!
Tuesday, 9 August 2011 - 09:14
Virtual Com Port with two USB-headers
I must say I don't understand the obsession of the DIY community to abuse standard connectors for their own signals. Snap connectors, high tensile connectors, micro connectors,...
Tuesday, 9 August 2011 - 09:02
Anybody ever make a 100 pin TQFP PCB ?
Never had a problem etching MSOP, TSSOP or TQFP in about any pitch. It's more a matter of choosing the right screen than getting complicated etching materials. at 55 to 65 degrees...
Tuesday, 9 August 2011 - 08:41
Pulse Width Modulation
Way too much biasing resistance on the gates. Coarse estimate top of my head the gate time constant with 10kohm and 12V for this type of power mosfet is between 10 and 50 micro...
Tuesday, 9 August 2011 - 01:03
why don't u like chinese pcb board
ignoramus wrote:Here is an example of yet another PCB shop going tits up Check the auction house records for the past few years for the sales...
Monday, 8 August 2011 - 23:03
Low cost battery backed RTC solutions?
Only way to find out is get quotes for both options. What was meant by the comment about not needing an RTC is that a new generation tiny (13A, 2313A, etc) will consume so little...
Friday, 5 August 2011 - 23:41
Pulse Width Modulation
Good point. Often starts near stall-current and drops off at a rate that's dependant on the motor design and application. For some designs start current can be assumed to be over...
Friday, 5 August 2011 - 22:08