US MEAS Piezoelectric Film Sensor Vibration Sensor - LDT Series

1. US MEAS Piezoelectric Film Sensor Vibration Sensor LDT Series Description:

LDT0 is a flexible element with silver paste electrodes screen-printed on a 28µm PVDF piezoelectric film. The film is laminated on a 0.125mm polyester substrate and has two crimp terminals. Because the piezoelectric film is offset from the neutral axis, bending creates high strain within the film, resulting in high voltage output. When the device is bent by direct contact, it acts as a flexible switch, and the output is sufficient to directly drive MOSFET or CMOS circuits. If the element is supported by the leads and vibrates freely, it acts as an accelerometer or vibration sensor. Adding a mass or changing the free-end length can adjust the resonant frequency and sensitivity for different applications. Multi-axis response can be achieved by offsetting the mass from the axis.

2. US MEAS Piezoelectric Film Sensor Vibration Sensor LDT Series Features:

(1) LDT0 as a vibration sensor --- Insert the crimp terminal pins through the PCB and solder them to the conductive pattern on the other side. Use a charge amplifier to detect the output signal from the vibration table (using a charge amplifier allows a longer measurement time constant, obtaining an 'open-circuit' voltage response). Add a small mass (approximately 0.26g) to one end of the sensor and measure again. Results are shown in Table 1, with overlapped plots in Figure 1. Without the mass, the resonant frequency of LDT0 is around 180Hz. Adding the mass at the end reduces the resonant frequency and increases the 'baseline' sensitivity.
(2) LDT0 as a flexible switch --- Using a charge amplifier to obtain 'open-circuit' voltage sensitivity, the output from deformation at the sensor's end can be measured (with the crimp terminal end fixed). A 2mm deformation is sufficient to produce 7V, and bending the sensor's end 90° can produce 70V (see Table 2, Figure 2).
(3) LDT0 frequency response --- Connecting a source capacitance of about 480pF to a resistive input load exhibits high-pass filter characteristics. Using an electronic noise source to generate broadband signals, the effects of various load impedances can be measured, and the -3dB point of the R-C filter can be determined (see Table 3, Figure 3).

3. US MEAS Piezoelectric Film Sensor Vibration Sensor LDT Series Applications:

Automotive anti-theft alarms

Vibration in horizontal drum washing machines

Electronic targets

Counter triggers

Vital signs monitoring

4. US MEAS Piezoelectric Film Sensor Vibration Sensor LDT Series Parameters:

Type	Piezoelectric film cantilever beam with mass
Output	High voltage output
Package	Film element
Operating Temperature Range	0～70℃
Accuracy	1.4V/g~16V/g
Power Supply	Passive
Features	Wide frequency (0.001Hz to 1000MHz), high sensitivity, high dielectric strength, low acoustic impedance, high stability
Electrical Connection	PCB mounting