Name of a componant

Thread Starter

Needhelp1232

Joined Jan 14, 2021
12
Hello, I recently posted a thread about the function of an electronic circuit and it helped me a lot. I am now looking for the name of a simple 6-pin component. The number on it has no reference on Google and i can not find any component looking exactly like this one after some researches. It looks like a 555 timer chip but with only 6 pins. Does someone know the name of this ? Thanks a lot in advance for the help.7E0D632B-C2FA-4AFF-972B-F6CB6573E974.jpeg
 

MrChips

Joined Oct 2, 2009
23,507
Often it would help if you gave us a bigger picture, literally speaking.
Show us a view of the entire board.
Do tell us the make and model of the device and at least its function. Knowing these items will give us additional clues as to what is your mystery component.
 

Thread Starter

Needhelp1232

Joined Jan 14, 2021
12
Often it would help if you gave us a bigger picture, literally speaking.
Show us a view of the entire board.
Do tell us the make and model of the device and at least its function. Knowing these items will give us additional clues as to what is your mystery component.
Sorry, there it is !
The function of the circuit is like a « sound grenade ». If you remove the trigger, a piezoelectric disc vibrates really fast and loud, which generates a very loud sound (130db). It works with 3 batteries and there is a 3 pin inductor (I think) that amplifies the electric signal (see the lady picture, the black cylinder)110404FF-D3CA-4030-99D2-F923E6C53194.jpeg585C8643-8E87-45C3-A258-958EAD52978C.pngCB1BA81C-5F58-4335-A815-8CF88E6CA3C5.jpeg77894A54-F7E8-4FC8-93CC-813F50A1F049.jpeg
 

jpanhalt

Joined Jan 18, 2008
11,088
I did a bit of searching for 3399Z earlier today, and the best I could come up with was a Richo linear voltage regulator (rn5rf-series ) with external transistor for higher current. That seemed appropriate given the transistor in near proximity and capacitor. Unfortunately, those devices are a similar package but with only 5-pins.

If it is an LDO voltage regulator, you can probably determine that by a few voltage measurements.
 

GeBJT

Joined Nov 3, 2020
19
It's taken a while, but here is my guess as to what might be inside the mystery IC "U1". The attached .asc is a simulation for a 2kHz piezo driver. Whether my speculation for U1 is right or wrong the simulation also illustrates how to use a step-up transformer to drive a high impedance resonant transducer.

2kHzPiezoSounder.png

Brief circuit notes

The oscillator is based around a configuration similar to a low voltage version of the 555. The main difference being the use of a stabilised reference for the timing components.

The oscillator frequency must be closely matched to the piezo resonance. I have assumed that this is achieved by selection of a 1% tolerance timing resistor R2. (200k in reality, 20k in simulation). I have also assumed that a capacitor of a few nF can be feasibly integrated (not certain about this). Possibly 3.45nF in reality, 34.5nF in simulation.

Electrical power to piezo is about 100mW, enough to make a loud noise but not the 130dBA as claimed by similar devices.

Yes, the inductor in the piezo equivalent cct (Lx1) really is 100Henry.

If you leave out the 2u "Maximum Timestep", you will get different results (why, is outside the scope of this note!).

Some interesting plots

V(lo) oscillator sawtooth waveform. R2 defines the length of the rising part.

V(vpz) approx -120V pulses which "hit" the piezo every 0.5mS.

(V(batt)-V(rl))*I(Rx1) electrical power dissipated in piezo. 2x oscillator frequency. Takes about 200mS (simulated) to stabilise.
 

Attachments

Thread Starter

Needhelp1232

Joined Jan 14, 2021
12
It's taken a while, but here is my guess as to what might be inside the mystery IC "U1". The attached .asc is a simulation for a 2kHz piezo driver. Whether my speculation for U1 is right or wrong the simulation also illustrates how to use a step-up transformer to drive a high impedance resonant transducer.

View attachment 232583

Brief circuit notes

The oscillator is based around a configuration similar to a low voltage version of the 555. The main difference being the use of a stabilised reference for the timing components.

The oscillator frequency must be closely matched to the piezo resonance. I have assumed that this is achieved by selection of a 1% tolerance timing resistor R2. (200k in reality, 20k in simulation). I have also assumed that a capacitor of a few nF can be feasibly integrated (not certain about this). Possibly 3.45nF in reality, 34.5nF in simulation.

Electrical power to piezo is about 100mW, enough to make a loud noise but not the 130dBA as claimed by similar devices.

Yes, the inductor in the piezo equivalent cct (Lx1) really is 100Henry.

If you leave out the 2u "Maximum Timestep", you will get different results (why, is outside the scope of this note!).

Some interesting plots

V(lo) oscillator sawtooth waveform. R2 defines the length of the rising part.

V(vpz) approx -120V pulses which "hit" the piezo every 0.5mS.

(V(batt)-V(rl))*I(Rx1) electrical power dissipated in piezo. 2x oscillator frequency. Takes about 200mS (simulated) to stabilise.
Wow thanks a lot man ! I didn’t expect such a big and precise help !
 
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