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AS5140H

Data Sheet - P i n A s s i g n m e n t s

Pins 1 and 2 are the magnetic field change indicators, MagINCn and MagDECn (magnetic field strength increase or decrease through variation

of the distance between the magnet and the device). These outputs can be used to detect the valid magnetic field range. Furthermore those

indicators can also be used for contact-less push-button functionality. Pins 3, 4 and 6 are the incremental pulse output pins. The functionality of

these pins can be configured through programming the one-time programmable (OTP) register:

Mode 1.x: Quadrature A/B Output

Represents the default quadrature A/B signal mode.

Mode 2.x: Step / Direction Output

Configures pin 3 to deliver up to 512 pulses (up to 1024 state changes) per revolution. It is equivalent to the LSB (least significant bit) of the

absolute position value. Pin 4 provides the information of the rotational direction.

Note:

Both modes (mode 1.x and mode 2.x) provide an index signal (1 pulse/revolution) with an adjustable width of one LSB or three LSB’s.

Mode 3.x: Brushless DC Motor Commutation Mode

In addition to the absolute encoder output over the SSI interface, this mode provides commutation signals for brushless DC motors with either

one pole pair or two pole pair rotors. The commutation signals are usually provided by 3 discrete Hall switches, which are no longer required, as

the AS5140H can fulfill two tasks in parallel: absolute encoder + BLDC motor commutation. In this mode,

- Pin 12 provides the LSB output instead of the PWM (Pulse-Width-Modulation) signal.

- Pin 8 (Prog) is also used to program the different incremental interface modes, the incremental resolution and the zero position into the

OTP (see page 21). This pin is also used as digital input to shift serial data through the device in Daisy Chain configuration, (see page 14).

- Pin 11 Chip Select (CSn; active low) selects a device within a network of AS5140H encoders and initiates serial data transfer. A logic high

at CSn puts the data output pin (DO) to tri-state and terminates serial data transfer. This pin is also used for alignment mode (see page

22) and programming mode (see page 19).

- Pin 12 allows a single wire output of the 10-bit absolute position value. The value is encoded into a pulse width modulated signal with 1µs

pulse width per step (1µs to 1024µs over a full turn). By using an external low pass filter, the digital PWM signal is converted into an ana-

log voltage, allowing a direct replacement of potentiometers.

PWM_LSB

12

Pulse Width Modulation of approx. 1kHz; LSB in Mode3.x

NC

13

For internal use. Must be left unconnected.

NC

14

For internal use. Must be left unconnected.

VDD3V3

15

3V-Regulator Output (see Figure 17)

VDD5V

16

Positive Supply Voltage 5V

Table 2. Pin Assignment for Different Incremental Output Modes

Output Mode

Pin 3

Pin 4

Pin 6

Pin 12

1.x: Quadrature

A

B

Index

PWM

2.x: Step/direction

LSB

Direction

Index

PWM

3.x: Commutation

U

V

W

LSB

Table 1. Pin Descriptions

Pin Name

Pin Number

Description