Search found 3762 matches
- Sun Oct 20, 2013 3:32 pm
- Forum: Dev: Hardware
- Topic: 121 pin connector 368255-2 (same as 1241434-1)
- Replies: 43
- Views: 58225
Re: Anyone to draw 121 pin connector?
I just e-mailed a file. See attached picture of the connector. It includes the PCB module with 3D and schematic symbol. I started a draft layout, however I ran out of time and I don't know the exact details you would look for. I think the files I'm sending are at a point where you can massage it int...
- Sat Oct 19, 2013 12:46 am
- Forum: Dev: Hardware
- Topic: Power supply - Sergey89
- Replies: 20
- Views: 22672
Re: Power supply - Sergey89
Typically a 6V transorber will dump significant current at 4.5 to 5V, which can skew an analog signal. Do you have a specific transorber you use? I like this buck regulator. The ripple is a bit high, however if it's set to something like 6V, then a LDO with a high ripple rejection like MAX1857 is us...
- Sat Oct 19, 2013 12:29 am
- Forum: Dev: Software
- Topic: wideband AFR sensor interface
- Replies: 21
- Views: 20230
Re: wideband AFR sensor interface
KICAD draft schematic for CJ125 chip found here https://hardware.open5xxxecu.googlecode.com/git-history/unfinished-unreviewed/KICAD_Project/O2_input_CJ125.sch
- Wed Oct 16, 2013 8:36 pm
- Forum: Dev: Hardware
- Topic: Power supply - Sergey89
- Replies: 20
- Views: 22672
Re: Power supply - Sergey89
I believe the MCU pin will be high impedance, so 0mA flow through the R9 resistor, and therefor no voltage drop. If you have the same voltage on both sides of that resistor, isn't that still to high for the MCU pin?
- Wed Oct 16, 2013 5:00 pm
- Forum: Dev: Hardware
- Topic: Power supply - Sergey89
- Replies: 20
- Views: 22672
Re: Power supply - Sergey89
I see 5.87504V in the area that I think is where the MCU pin would need to stay under 5.3V. Am I reading this correctly? I once posted a hacked together wiki about AN/Digi protection it's found here https://code.google.com/p/daecu/wiki/AN_and_DIGI_Protection Sorry it's very un-polished, however the ...
- Wed Oct 16, 2013 10:34 am
- Forum: Dev: Hardware
- Topic: Actuators driver - Sergey89
- Replies: 3
- Views: 5314
Re: Actuators driver - Sergey89
Beware .1 to .01 ohm connections in P30. They can create tank circuit which can cause stepper motor failures by creating excessive voltage spikes.
- Wed Oct 16, 2013 10:32 am
- Forum: Dev: Hardware
- Topic: Triggers - Sergey89
- Replies: 2
- Views: 5147
Re: Triggers - Sergey89
I'm not seeing the need for these buffers, the MCU input is already high impedance. Perhaps the goal is to have a replaceable component in hopes you'll protect the MCU.
- Wed Oct 16, 2013 10:29 am
- Forum: Dev: Hardware
- Topic: Analog inputs - Sergey89
- Replies: 6
- Views: 8320
Re: Analog inputs - Sergey89
With the clamping diodes I don't see much of need for the op-amp. I guess you get the drop from 5V to 3V, however you can do that with a resistor divider. I don't see much of a need for R9 or C5. Perhaps that op-amp is sensitive to RF noise on the front end. C1 - C4 are not ESD protected, they could...
- Wed Oct 16, 2013 10:21 am
- Forum: Dev: Hardware
- Topic: analog inputs: op-amp + divider - Russian - now MCP6004
- Replies: 124
- Views: 141549
Re: analog inputs: op-amp + divider - Russian
The 150 ohm and .01uF are a very high cut off low pass filter. Those are commonly used on the output of the op-amp. The op-amp is a high gain device, when making a rapid change it can cause some high frequency ringing. This clamp simply blocks high frequency RF from coming out of the op-amp. Because...
- Wed Oct 16, 2013 10:04 am
- Forum: Dev: Hardware
- Topic: Power supply - Sergey89
- Replies: 20
- Views: 22672
Re: Power supply - Sergey89
All in all, not a bad regulator layout. However it's very inefficient, and you'll have to ensure you remove those BTU's to maintain a large temperature range. If you are running 1A on the 5V with a 16V battery, you'll be dissipating (16-5) * 1 = 11 watts of energy. That's 11 watts wasted to provide ...
- Wed Oct 16, 2013 9:32 am
- Forum: Dev: Hardware
- Topic: Injectors driver - Sergey89
- Replies: 4
- Views: 8047
Re: Injectors driver - Sergey89
OEM's have lots of control over how things are manufactured, so they can predict and control things very well. Most notably is the low side impedance when under full injector loads. As an example, if you have 8 cyl, with small injectors, such that you run 99% duty, you'll have a min of 8 amps flowin...
- Tue Oct 15, 2013 5:04 pm
- Forum: Dev: Hardware
- Topic: analog inputs: op-amp + divider - Russian - now MCP6004
- Replies: 124
- Views: 141549
Re: analog inputs: op-amp + divider - Russian
BAT199 has is a bit long in the tooth relative to reverse recovery time coming in at 3uS. I have used the BAT54 for similar with a reverse recovery of 5nS. I also like that the voltage drop on the BAT54 is lower. It drops .1V at 1mA where the BAT199 drops .9V. When I used the BAT54, my goal was to l...