AS5035 – 64 PPR INCREMENTAL MAGNETIC ROTARY ENCODER

Revision 1.5

www.austriamicrosystems.com

Page 6 of 17

7.1

OTP Programming Timing

OTP programming requires access to the factory settings

register of the AS5035. Improper or accidental modification

of the factory settings may render the chip unusable.

Therefore the Zero Position and CCW programming is

recommended only with austriamicrosystems proprietary

hardware and software.

Note: During the programming process, the transitions in

the programming current may cause high voltage spikes

generated by the inductance of the connection cable. To

avoid these spikes and possible damage to the IC, the

connection wires, especially the signals Prog and VSS

must be kept as short as possible. The maximum wire

(see Figure 6) should not exceed 50mm (2 inches). To

suppress eventual voltage spikes, a 10nF ceramic

capacitor should be connected close to pins Prog and VSS.

This capacitor is only required for programming, it is not

required for normal operation.

ensure that the signal Prog is stable at the rising edge of

CLK (see Figure 7). Additionally, the programming supply

voltage should be buffered with a 10µF capacitor mounted

close to the switching transistor. This capacitor aids in

providing peak currents during programming.

The specified programming voltage at pin Prog is 7.3 –

7.5V (see section 12.8). To compensate for the voltage

drop across the VPROG switching transistor, the applied

programming voltage may be set slightly higher (7.5 -

8.0V).

7.1.1

CCW Bit Programming

The absolute angular output value, by default, increases

with clockwise rotation of the magnet (top view). Setting

the CCW-bit (see Figure 7) allows for reversing the

indicated direction, e.g. when the magnet is placed

underneath the IC:

CCW = 0 – angular value increases clockwise;

CCW = 1 – angular value increases counterclockwise.

Note: Further information on the required hardware and

software for Zero Position programming of the AS5035 can

be

found

in

the

“AS5035”

section

of

the

austriamicrosystems website:

http:www.austriamicrosystems.com

( Rotary Encoders AS5035)

Figure 7: Programming access – write data (first section of Figure 8)

Figure 8: Complete programming sequence