Go Down

### Topic: how to rectifiy the 100 Khz sine wave signal (Read 1 time)previous topic - next topic

#### arulselvam

##### Nov 09, 2017, 10:10 pm
hi friends, i have 5V peak to peak output 100 Khz sine wave signal from sensor, i want to rectify this signal as DC how i can achieve this task. please help me

#### jremington

#1
##### Nov 09, 2017, 10:35 pmLast Edit: Nov 09, 2017, 10:35 pm by jremington
A diode is often used to rectify signals.

If you want to read the signal directly with the ADC, then offset the signal by 2.5V DC, as shown in this AC voltage monitor circuit.

#### raschemmel

#2
##### Nov 09, 2017, 10:44 pm
Full Wave Bridge Rectifier

D1 -D4 = 1n4001 diodes
C = 470uF to 1000uF

(values based on low current load. Since load current or application were not specified, power supply cannot be designed specifically for a load that was not specified.
Arduino UNOs, Pro-Minis, ATMega328, ATtiny85, LCDs, MCP4162, keypads,<br />DS18B20s,74c922,nRF24L01, RS232, SD card, RC fixed wing, quadcopter

#### Wawa

#3
##### Nov 09, 2017, 10:48 pm
Depends what you want to do with that signal.
Only detect if it's there?
Measure it's peak/peak voltage, or frequency?
Is it a digital 0-5volt signal, or AC centered around ground?

@raschemmel
A 1N400x is too slow for 100kHz.
Leo..

#### arulselvam

#4
##### Nov 09, 2017, 11:40 pm
Depends what you want to do with that signal.
Only detect if it's there?
Measure it's peak/peak voltage, or frequency?
Is it a digital 0-5volt signal, or AC centered around ground?

@raschemmel
A 1N400x is too slow for 100kHz.
Leo..
i want to measure peak to peak value its ac signal from xr2206

#### arulselvam

#5
##### Nov 10, 2017, 12:31 am
can i use UF4007 diode to rectify this signal

#### larryd

#6
##### Nov 10, 2017, 12:38 am
Try 1N4148 (1N914), experiment with output capacitors and load values.

.
No technical PMs.
The last thing you did is where you should start looking.

#### Wawa

#7
##### Nov 10, 2017, 12:40 am
Yes, a 1N4148 would be better
And reduce the buffer cap to 100n.
Leo..

#### raschemmel

#8
##### Nov 10, 2017, 03:12 am
100,000 Hz/60 Hz = 1666

1000 uF/1666 = 0.6 uF
Arduino UNOs, Pro-Minis, ATMega328, ATtiny85, LCDs, MCP4162, keypads,<br />DS18B20s,74c922,nRF24L01, RS232, SD card, RC fixed wing, quadcopter

#### Wawa

#9
##### Nov 10, 2017, 03:31 am
Smoothing cap value needed depends on load resistor value (you need one).
If there is no load (very high impedance input pin), then rectified voltage on the cap will stay there for a long time.
As larryd said: experiment with output capacitors and load values.

You might not need a full bridge if XR2206 and Arduino grounds are shared.
Leo..

#### JohnRob

#10
##### Nov 10, 2017, 05:41 am
Do you have an accuracy goal.  With a 5V P-P signal the diode drop 0.3 to 0.5 v is a large portion of you signal.  Is that adequate for what you need?

There are precision rectifier circuits which basically is an opamp with the diode inside the feedback loop.  For a 100k Hz you would have to carefully choose your components.

#### MarkT

#11
##### Nov 10, 2017, 11:57 am
At least use schottky diodes to rectify, not 1N4148 or 1N400x series!!
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

#### 6v6gt

#12
##### Nov 11, 2017, 08:24 am
hi friends, i have 5V peak to peak output 100 Khz sine wave signal from sensor, i want to rectify this signal as DC how i can achieve this task. please help me
What sensor (link) and what are you going to do with the rectified  result ?
You may be able to attempt a signal processing treatment of your input signal eg subtracting 2.5 and returning the absolute value of the voltage, but an Arduino may be too slow for any elaborate processing here.

#### raschemmel

#13
##### Nov 11, 2017, 11:29 amLast Edit: Nov 11, 2017, 11:31 am by raschemmel
EXAR 2206

(Supply Voltage = 10Vdc, hence +/- 5V AC out)
Arduino UNOs, Pro-Minis, ATMega328, ATtiny85, LCDs, MCP4162, keypads,<br />DS18B20s,74c922,nRF24L01, RS232, SD card, RC fixed wing, quadcopter

#### allanhurst

#14
##### Nov 11, 2017, 12:10 pm
Do you have an oscilloscope? - that's the obvious way...

Allan

Go Up