Triggering HCSR-04 (Ultrasonic sensor) With 555 Timer IC

Siddu B's picture

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Triggering HCSR-04 (Ultrasonic sensor) With 555 Timer IC
September 27, 2016 - 10:49am

Dear Sir/Madam

 

I want to Trigger Ultrasonic sensor (HCSR04) with 555 Timer IC(By generating 10us) , Insted of connecting to the MCU . Is it possible......

Please kindly let me know.....

Thanking you.... 

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Configure a 555 (IC:A) to
September 28, 2016 - 5:39pm

Configure a 555 (IC:A) to generate square waves (astable multivibrator) at low frequency, say 50 Hz.

Connect output of IC:A to the reset pin of another 555 (IC:B)

Configure 555 (IC:B) for to generate square waves (astable multivibrator) at 100 kHz to generate the 10us pulse you require.

Connect the output of IC:B to the trigger pin of HCSR04.

This way you trigger HCSR04 once every 20ms.

 

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I missed one point:
September 28, 2016 - 5:42pm

I missed one point:

Connect output of IC:A to a monoshot (74123), which is configured for 10 us duration.

Connect its output to the trigger pin of HCSR04.

No need to use IC:B.

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Thank You Very Much Ashok....
September 29, 2016 - 9:32am

Thank You Very Much Ashok.....

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74HC123N
October 26, 2016 - 5:19pm

Hi Bro

I bought 74HC123N

but i made connection as per datasheet , i could not get the output...

can you please help me