AS5035 – 64 PPR INCREMENTAL MAGNETIC ROTARY ENCODER

Revision 1.5

www.austriamicrosystems.com

Page 3 of 17

5

Connecting the AS5035

5.1

Power Supply

5.1.1

5.0V Operation

Connect a 4.5V to 5.5V power supply to pin VDD5V only.

Add a 1µF to 10µF buffer capacitor to pin VDD3V3

5.1.2

3.3V Operation

Connect a 3.0V to 3.6 V power supply to both pins VDD5V

and VDD3V3. If necessary, add a 100nF ceramic buffer

capacitor to pin VDD3V3.

LDO

I

N

T

E

R

F

A

C

E

2.2...10µF

100n

4.5 - 5.5V

A

Index

B

VDD3V3

VSS

VDD5V

5V Operation

Internal

VDD

CSn

LDO

100n

3.0 - 3.6V

VDD3V3

VSS

VDD5V

3.3V Operation

Internal

VDD

I

N

T

E

R

F

A

C

E

A

Prog

OTP_CLK

OTP_DO

Index

B

CSn

Prog

OTP_CLK

OTP_DO

Figure 4: Connections for 5V / 3.3V supply voltages

5.2

Logic High and Low Levels

VDD5V will be either 3.0 - 3.6V or 4.5 - 5.5V, depending on

configuration.

In either case, the logic levels on output pins A, B and

Index will be

Vout high = VDD5V – 0.5V,

Vout low = VSS+0.4V.

The logic level on the CSn input pin will be

Vin high = VDD5V*0.7,

Vin low = VDD5V*0.3

5.3

Output Current

The available maximum output current on pins A, B and

Index to maintain the Vout high and Vout low levels is

2mA (sink and source) at VDD5V = 3.0V

4mA (sink and source) at VDD5V = 4.5V

5.4

Chip Select Pin CSn

5.4.1

Without Power-up Diagnostic Feature

For standalone operation without microcontroller, pin CSn

should be connected to VSS permanently. The incremental

outputs will be available, as soon as the internal offset

compensation is finished (within <50ms).

5.4.2

With Power-up Diagnostic Feature

A diagnostic feature is available to detect a temporary loss

of

power

or

initial

power-up

of

the

AS5035:

if the CSn pin is high or left open (internal pull up resistor

~50k

Ω) during power-up, the incremental outputs will

remain in high state: A = B = Index = High.

This state indicates a power-up or temporary loss of power,

as in normal operation A, B and Index will never be high at

the same time. When Index is high, both A and B are low.

To clear this state end enable the incremental outputs,

CSn must be pulled low. The incremental outputs will

remain enabled if CSn returns to high afterwards.