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AS5134

Datasheet - Application In form atio n

Figure 17. OTP Programming Connection

Note: The maximum capacitive load at PROG in normal operation is less than 20pF. However, during programming the capacitors C1+C2 are

needed to buffer the programming voltage during current spikes, but they must be removed for normal operation. To overcome this

setup), if the capacitors can not be removed at final assembly.

During programming the OTP, the diode ensures that no current is flowing from PROG (8-8.5V) to VDD (5V).

In the standard case (see Figure 17), the verification of a correct OTP readout can be done either by analog readback of the OTP reg-

ister or with the aid of the OTP_OK bit. The special case setup provides only the OTP_OK bit for verifying the correct reading of the

The OTP_OK bit can be accessed with command #4 (see Table 9).

As long as the PROG pin is accessible it is recommended to use standard setup. In case the PROG pin is not accessible at final

assembly, the special setup is recommended.

8.1.2 Programming Verification

After programming, the programmed OTP bits must be verified in two ways:

information. Otherwise, it indicates that the programming was not performed correctly.

Note: Either “Digital Verification” or “Analog Verification” must be carried out in addition to the “Digital Read Out”.

i) At room temperature

ii) Right after the programming

analog voltage with each clock representing a sequence of the bits in the OTP register (starting with D61). A voltage of <500mV indicates a

correctly programmed bit (“1”) while a voltage level between 2V and 3.5V indicates a correctly unprogrammed bit (“0”). Any voltage level in

between indicates incorrect programming.

PROG

GND

C1

C2

100nF

10µF

PROM Cell

maximum

parasitic cable

inductance

L<50nH

Standard Case

PROG

GND

C1

C2

100nF

10µF

PROM Cell

L<50nH

Special Case

Remove for normal operation