I have a small IR sensor that needs a 10uf cap near Vcc and GND per the spec sheet and wondered would be the best way to attach it. Should I somehow try to solder it or just cut the lead wires and solder it to them. I just want it to look nice and not just a hack job, which is what I excel in.
I would solder it to the power pins you see on the 'front' of the sensor.
Can you get to the back of the pins, so you can solder a SMD capacitor which will not look like a hack job if you solder it nicely. I cannot give you a more definitive answer as the the pinout has not been presented. If they are side by side a piece of cake.
On the back of the pin connector part of the PCB there's room for a 10uF 1206 ceramic cap across the pins, assuming
you don't need to wire it between the two outer pins, which would need a short piece of wire too.
Hi,
Can you post a link to the spec/datasheet of the IR sensor please?
Personally I would solder it outside at the socket pins, 10uF of any voltage rating will be a squeeze on the pcb.
Tom.... 
10uF MLCC caps are available down to 0402 for lower voltages, there's loads of room!
10uF 1206 size are available upto a voltage rating of upto 50V
Have you tested (externally) that the extra capacitance solves the problem?
If you refer to the timing chart in the datasheet, it shows that you'll need to avoid the first measurement.
Thanks for the help.
I was going to solder but the last time I made a mess of it and had to throw it out(glad is was only a $2 component).
The outer 2 pins on the left are the Vcc and Gnd pins in the photo posted by @TomGeorge.
It specifically states a by-pass capacitor of 10uf or larger to stabilize power, all I have are 10uf electrolytic caps or a 0.1uf ceramic cap at the moment.
I was going to power it with 3.3V,
Here is the spec sheet
IR sensor.pdf (1.06 MB)
dlloyd:
Have you tested (externally) that the extra capacitance solves the problem?
If you refer to the timing chart in the datasheet, it shows that you'll need to avoid the first measurement.
I don't need any immediate measurements from the sensor, I was installing the cap because on my last project I was installing caps to smooth out all the noise interference on all the components I used so a few pennies more upfront will save headaches later was my thinking.
From the datasheet:
In order to stabilize power supply line, we recommend to connect a by-pass capacitor of 10F or more between Vcc and GND near this product.
Hmm ... so its a "SHARP" decision to not include adequate filtering on the PCB, then have no easy means for the user to add the cap near the unit. This is not a "sharp" decision!
Does the connector to this sensor already exist? If not, you could maybe crimp the cap leads in with the connector wiring and avoid soldering altogether. It doesn't state the cap has to be mounted on the board.
we recommend to connect a by-pass capacitor of 10F or more between Vcc and GND near this product.
MarkT:
10uF MLCC caps are available down to 0402 for lower voltages, there's loads of room!
That's pretty impressive, I didn't know those come that small! However at 5V the capacitance is probably reduced to 1-2µF... ceramic caps suffer from decreasing capacitance when the voltage increases, the smaller the part the stronger this effect.
Considering the capacitance recommended (10 µF or more) physical placement shouldn't matter too much, either end of the supply wires should do (assuming they are not particularly long), as long as from the cap the wires go to only the sensor, and nothing else.
dlloyd:
From the datasheet:
In order to stabilize power supply line, we recommend to connect a by-pass capacitor of 10F or more between Vcc and GND near this product.
Hmm ... so its a "SHARP" decision to not include adequate filtering on the PCB, then have no easy means for the user to add the cap near the unit. This is not a "sharp" decision!
That's funny you say that. I wonder that all the time with the components I have used(Hall sensor, Prox. switch, buttons etc. all require them) If they need them put them on, I'm sure everyone wouldn't mind paying a couple pennies more. I always thought they left them off because every application would require something different.
wvmarle:
Considering the capacitance recommended (10 µF or more) physical placement shouldn't matter too much, either end of the supply wires should do (assuming they are not particularly long), as long as from the cap the wires go to only the sensor, and nothing else.
The Arduino is a long ways away from the sensor so I always put them as near to the sensor as I can.
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