Press Release
November 14, 2005
Epson Toyocom Introduces High-Precision Pressure Sensor with Quartz Oscillator
Epson Toyocom Corporation has boosted its lineup of sensors by introducing its new TSU Series of high-precision quartz pressure sensors, which use quartz oscillators to obtain high-precision pressure measurements. The new lineup can be employed in instruments used in measuring environmental factors such as water level monitors for dams and rivers, as well as in security solutions and other application fields. Sample shipments will begin in late November 2005.
The new TSU Series products use pressure-related fluctuations in their built-in crystal unit's frequency to implement a quartz pressure sensor. By incorporating a double-ended tuning fork crystal unit(*1) that has superb stability and quick responsiveness, these products allow high-precision pressure measurements to be performed with high sensitivity as well as good reliability(*2), hysteresis(*3), and temperature characteristics. By building in the oscillator circuit, Epson Toyocom has enabled frequency output directly from these products, which reduces the effects of the cable length and facilitates use in various types of equipment.
These products will be featured in equipment demonstrating their high sensitivity by the Chuou Kakoki Shoji Co., Ltd. at their booth (No. East 1H3-01) at the INCHEM TOKYO 2005 Chemical Plant Engineering Show, scheduled for November 15 to 18 at Tokyo Big Sight.
Epson Toyocom continues to promote its R&D program to suchin products as part of its "3D" strategy(*4), to serve a wide array of applications in the sensor industry.
| Item | Symbol | TSU-10GL | TSU-20G | TSU-70G | TSU-100G |
| Pressure measurement range | － | 0 to 100 kPa | 0 to 200 kPa | 0 to 700 kPa | 0 to 1 MPa |
| Linearity after linearization | － | 0.1 %FS Max. | 0.05 %FS Max | ||
| Repeatability | － | 0.005 %FS Typ. | |||
| Hysteresis | － | 0.008 %FS Typ. | |||
| Operating temperature range | T_use | -10°C to +70°C | |||
| Storage temperature range | T_stg | -20°C to +80°C | |||
| Operating humidity range | － | 0% to 95% | |||
| Tilt correction | － | None | Equipped | ||
| Built-in temperature sensor | － | None | Option | Option | Option |
| Output frequency without pressure | － | 39 kHz Typ. | |||
| Maximum frequency change | Hz | 4,000 Hz Typ. | |||
| Output waveform | － | Rectangular wave | |||
| Output voltage | Vp-p | 3.2 Vp-p (output load 600Ω) | |||
| Supply voltage | VCC | 12 V (Standard) | |||
| Current consumption | Icc | 2 mA Typ. (output load 600Ω) | |||
| Pressure input/output port | － | PT 1/8" | |||
| Weight | － | 200 g | |||
| Material | － | SUS304 | |||
*1. Double-ended tuning fork crystal unit: as shown in Figure 1, this uses the flexure vibration of two combined tuning fork type crystal units. It features a high Q (resonance sharpness) value, excellent stability, high precision, and fast responsiveness.
(Figure 1)
*2. Good reliability: the same results can be obtained from numerous measurements, which is a sign of high precision.
*3. Hysteresis: this is the differential between a value measured after the voltage has changed from low level to high level and a value measured after the voltage has changed from high level to low level. A smaller hysteresis value means higher precision.
*4. 3D strategy: a strategy based on Epson Toyocom's three main product categories: timing devices, sensing devices, and optical devices.
Timing devices: Crystal units, resonators, oscillators, real-time clock modules, filters, etc.
Sensing devices: Gyro sensors and other devices that convert physical entities into electrical signals
Optical devices: Optical Low Pass Filters (OLPFs) for image correction in digital cameras, optical pickups for DVD drives, etc.
- Operation principle of high-precision quartz pressure sensor
When stress is applied to a twin tuning fork quartz oscillator, its resonance frequency becomes almost linear (see Figure 2 below). By taking advantage of this property, the twin tuning fork quartz oscillator in flexure vibration mode (highly sensitive to stress) can be used as a pressure -sensitive device.
(Figure 2)
