AS5140H Automotive Rotary Encoder IC

Description

The AS5140H is a contactless magnetic rotary encoder for accurate angular measurement over a full turn of 360° and over an extended ambient temperature range of -40°C to 150°C.

It is a system-on-chip combining integrated Hall elements, analog front end and digital signal processing in a single device.

To measure the angle, only a simple 2-pole magnet rotating over the center of the chip is required.
The magnet may be placed above or below the IC.

The absolute angle measurement provides instant indication of the magnet’s angular position with a resolution of 0.35° = 1024 positions per revolution. This digital data is available as a serial bit stream and as a PWM signal. Furthermore, a user-programmable incremental output is available.

An internal voltage regulator allows the AS5140H to operate at either 3.3V or 5V supplies.

The AS5140H is pin-compatible to the AS5040; however it uses low-voltage OTP programming cells with additional programming options.

Key Features

• Contactless high resolution rotational position encoding over a full turn of 360°
• 2 digital 10-bit absolute outputs:
  • Serial interface and
  • Pulse width modulated (PWM) output
• 3 incremental output modes:
  • Quadrature A/B and Index output signal
  • Step / Direction and Index output signal
  • 3-phase commutation for brushless DC motors
  • 10-, 9-, 8- or 7-bit user programmable resolution
• User programmable zero / index position
• Failure detection mode for magnet placement monitoring and loss of power supply
• Rotational speeds up to 10,000rpm
• Push button functionality detects movement of magnet in Z-axis
• Serial read-out of multiple interconnected AS5140H devices using daisy chain mode
• Fully automotive qualified to AEC-Q100, grade 0
• Wide ambient temperature range: -40°C to 150°C
• Small Pb-free package: SSOP-16 (5.3mm x 6.2mm)

Applications

• Automotive applications:
  • Engine compartment sensors
  • Transmission gearbox encoder
  • Throttle valve position control
• Industrial applications
  • Rotary sensors in high temperature environment

Block Diagram