AS5043

Data Sheet – Analog Readback Mode

www.austriamicrosystems.com

Revision 1.80

18 – 36

13 Analog Readback Mode

Non-volatile programming (OTP) uses on-chip zener diodes, which become permanently low resistive when subjected to

a specified reverse current.

The quality of the programming process depends on the amount of current that is applied during the programming

process (up to 130mA). This current must be provided by an external voltage source. If this voltage source cannot

provide adequate power, the zener diodes may not be programmed properly.

In order to verify the quality of the programmed bits, an analog level can be read for each zener diode, giving an

indication whether this particular bit was properly programmed or not.

To put the AS5043 in Analog Readback Mode, a digital sequence must be applied to pins CSn, PROG and CLK as

shown in Figure 15. The digital level for this pin depends on the supply configuration (3.3V or 5V; see section 1, page 5).

The second rising edge on CSn (OutpEN) changes pin PROG to a digital output and the log. high signal at pin PROG

must be removed to avoid collision of outputs (grey area in Figure 15).

saved as a reference for the calculation of the subsequent programmed and unprogrammed OTP bits.

Following this step, each rising slope of CLK outputs one bit of data in the reverse order as during programming.

(see Figure 15: Output Range OR0 and -1 , ClampMdEn, RefExtEn, FB_IntEn, Z0…Z9, ccw)

During analog readback, the capacitor at pin PROG (see Figure 12) should be removed to allow a fast readout rate.

gives an indication on the quality of the programmed bit: a reading of <100mV indicates a properly programmed bit and a

reading of >1V indicates a properly unprogrammed bit.

A reading between 100mV and 1V indicates a faulty bit, which may result in an undefined digital value, when the OTP is

read at power-up.

Following the 16

Figure 15: Analog OTP Register Read

In te rn al

te st bit

dig it al

CS n

CL K

1

16

PROG

Pro g EN

OR 1

OR 0

A n a log R e a d b a ck D ata a t P R O G

Ou tpE N

Prog ch an ges t o O u tput

Powe r-o n -

R e s e t;

c ycle supply

Ref Ext

EN

Clamp

Md EN

Z6

Z5

Z 8

Z7

ccw

Z9