Summary of CambridgeIC gets design win Start-up
The CAM204 is a single-chip resonant inductive position sensor IC offering ratiometric measurements, SPI slave communication, user I/Os, support for up to four sensors, and external DAC drive. It delivers 10–16 bit noise-free resolution, automatic resonator tuning, high update rates, wide temperature range, and operation from a single 2.7–3.6 V supply. CambridgeIC’s CAM204 underpins Turck’s Ri Series angle sensors, using a PCB coil assembly and a passive LC resonator target for robust, high-gap, magnetically tolerant angle and displacement sensing.
Parts used in the CAM204 project:
- CAM204 single-chip resonant inductive position sensor IC
- PCB with three coils (one excitation coil, two sensor coils)
- Passive LC resonant circuit (ferrite-cored coil and capacitor)
- External DAC (optional, for up to 4 analog outputs)
- SPI interface wiring (for SPI slave communications)
- User IO connections (for position triggers and sample indicators)
- Power supply 2.7–3.6 V
- Enclosure or plastic housing (sensor can be housed behind thick plastic)
CAM204
The CAM204 is a single-chip non-contact position sensor IC for resonant inductive position sensing.
Features
- Resonant inductive position sensing engine
- Fully ratiometric measurements
- SPI communications (slave device)
- User IOs for position triggers and sample indicators
- Measures up to 4 sensors
- Can drive external DAC for up to 4 analog outputs
- Internal software upgradable over SPI
Performance
- Noise Free Resolution 10…16 bits at typical gap, depending on sensor
- Automatic tuning to resonators across ±7% frequency range
- < ±0.1% position change across temperature
- Update rate > 1000 samples/s (Type 1 sensors)
- Single 2.7…3.6V supply
- -40°C to +125°C (CAM204BE)
Fabless sensing chip firm CambridgeIC is providing the technology behind Turck’s latest angle sensor family, its Ri Series.
‘Resonant inductive position sensing’ is CambridgeIC’s fundamental technology, which is implemented inside its chip, the CAM204 – announced at Electronica late last year.
The sensor element is a PCB with tracks defining three coils – one for excitation, and two sensor coils which connect to the chip.
This measures displacement or angle compared with a moving target, which consists of a passive LC resonant circuit – a ferrite-cored coil connected to a capacitor, for example.
“The technology is a high-tech version of the older resolver, synchro and RVDT technologies,” said CambridgeIC. “A coil and capacitor form a simple electrical resonator which replaces the stator. Using a resonant circuit means large signal levels even at big gaps, so that the sensor can be housed behind a thick plastic housing.”
Compared with sensors that detect a magnet’s angle using Hall effect or magnetoresistive sensor elements, claims the firm, its system is tolerant of magnetic fields experienced near drives, motors and electrical welders. And no alignment bearings are required because the technology is tolerant of some misalignment.
For more read: CambridgeIC gets design win Start-up
- What is the CAM204?
The CAM204 is a single-chip non-contact resonant inductive position sensor IC. - How many sensors can the CAM204 measure?
It can measure up to 4 sensors. - Does the CAM204 support digital communication?
Yes, it supports SPI communications as a slave device. - Can the CAM204 drive analog outputs?
Yes, it can drive an external DAC for up to 4 analog outputs. - What resolution does the CAM204 provide?
Noise free resolution is 10 to 16 bits at typical gap depending on sensor. - How tolerant is the CAM204 to temperature changes?
It provides less than ±0.1% position change across temperature and operates from -40°C to +125°C for CAM204BE. - What supply voltage does the CAM204 require?
It requires a single 2.7 to 3.6 V supply. - How fast can the CAM204 update position measurements?
Update rate is greater than 1000 samples per second for Type 1 sensors. - What kind of target does the CAM204 sense against?
It senses displacement or angle against a passive LC resonant circuit such as a ferrite-cored coil connected to a capacitor. - Is the CAM204 tolerant of external magnetic fields?
Yes, the technology is tolerant of magnetic fields encountered near drives, motors, and electrical welders.
