Broadcom AR25 Reflective Absolute Single-Turn Encoder
Broadcom® AR25 25-Bit Reflective Absolute Single-Turn Encoder is a miniature absolute encoder ASIC designed to cater to the growing demand for space-constrained applications. Employing advanced reflective optical-encoding theory, the AR25 series offers high position accuracy with a correction algorithm that is unattainable by magnetic encoders.
The AR25 encoder is a one-chip solution that offers flexibility to accommodate variable overall diameters, ranging from 30mm to 60mm. The AR25 also supports through-hole solutions up to 30mm in diameter. User-programmable resolutions are from 15-bit to 25-bit single-turn absolute outputs. In addition, the AR25 also provides differential analog sine/cosine or digital incremental ABIUVW signals with configurable CPRs and pole pairs. The AR25 also features a state-of-the-art auto-calibration function that simplifies integration into the user's end systems.
The AR25 series also supports integration with the Broadcom proprietary battery-less Energy Harvesting MultiTurn (EHMT) solution. Alternatively, other multi-turn solutions, such as gear-based and battery backup, are also supported by a dedicated MT interface port. For power supply, the ASIC supports dual-mode operating voltages of either 3.3V or 5V, which are suitable for handheld and portable device applications. The operating temperature range is -40°C to 125°C, ideal for most industrial applications.
To enhance user system design flexibility, the AR25 offers various protocols that the user can select. Among the available protocols are the Encoder Serial Link (ESL) or RS-485 half-duplex protocol, SSI, BiSS-C, and SPI 4-wire.
Features
- 6mm × 6mm × 1.05mm (L x W x H) miniature surface-mount QFN package
- User-programmable absolute resolution of 15 bits to 25 bits
- User-programmable incremental output (ABI) resolutions ranging from 1 CPR to 220 CPRs
- User-programmable commutation signals (UVW) ranging from 1 to 32 pole-pairs
- High-temperature range of –40°C to 125°C, suitable for most industrial operations
- Dual-mode operating voltages of 3.3V and 5V, enabling handheld and portable device applications
- Multi-turn integration (EHMT, gear, or battery backup)
- Optical radius (ROP) flexibility (blind-hollow or throughshaft applications)
- Built-in line transceiver for protocol with selectable drivability strength
- Auto-accuracy calibration with a constant speed that is one click away
- Selectable communication protocols
- RS485 (2.5/5/10Mb/s)
- ESL (2.5/5/10Mb/s)
- SSI 2-wire (up to 10MHz)
- SPI 4-wire (up to 10MHz)
- BiSS-C (up to 10MHz)
- External memory supports up to 128Kb
- Built-in temperature sensor
- RoHS-compliance
Applications
- Robotic automation and engineering
- Factory automation and drone
- Medical and dental devices and equipment
- High-accuracy portable and handheld devices
- Miniature motor, servo motor, and linear actuator
- Through-shaft motor, gear motor, and speed reducer
Datasheets
Block Diagram
