AS5040

Data Sheet

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Revision 2.10

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Table 2 Pin Description SSOP16

Pin

Symbol

Type

Description

1

MagINCn

DO_OD

Magnet Field Magnitude INCrease; active low, indicates a distance

reduction between the magnet and the device surface.

2

MagDECn

DO_OD

Magnet Field Magnitude DECrease; active low, indicates a distance

increase between the device and the magnet.

3

A_LSB_U

DO

Mode1.x:

Quadrature A channel

Mode2.x: L

east Significant Bit

Mode3.x: U

signal (phase1)

4

B_Dir_V

DO

Mode1.x

: Quadrature B channel quarter period shift to channel A.

Mode2.x: Dir

ection of Rotation

Mode3.x: V

signal (phase2)

5

NC

-

Must be left unconnected

6

Index_W

DO

Mode1.x and Mode2.x

: Index signal indicates the absolute zero position

Mode3.x

: W signal (phase3)

7

VSS

S

Negative Supply Voltage (GND)

8

Prog

DI_PD

OTP Programming Input and Data Input for Daisy Chain mode. Internal

pull-down resistor (~74k

Ω).

May be connected to VSS if programming is not used

9

DO

DO_T

D

ata Output of Synchronous Serial Interface

10

CLK

DI, ST

Cl

ock Input of Synchronous Serial Interface; Schmitt-Trigger input

11

CSn

DI_PU, ST

C

hip Select, active low; Schmitt-Trigger input, internal pull-up resistor

(~50k

Ω) connect to VSS in incremental mode (see 0)

12

PWM_LSB

DO

P

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

13

NC

-

Must be left unconnected

14

NC

-

Must be left unconnected

15

VDD3V3

S

3V-Regulator Output (see Figure 19)

16

VDD5V

S

Positive Supply Voltage 5 V

DO_OD

digital output open drain

S

supply pin

DO

digital output

DI

digital input

DI_PD

digital input pull-down

DO_T

digital output /tri-state

DI_PU

digital input pull-up

ST

Schmitt-Trigger input

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 AS5040 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 18).

This pin is also used as digital input to shift serial data through the device in Daisy Chain configuration,

(see page 11).

Pin 11 Chip Select (CSn; active low) selects a device within a network of AS5040 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 (page 21) and programming mode (page 16).