STPM12ATR datasheet(24/43 Pages) STMICROELECTRONICS

24 / 43 page

Theory of operation

STPM11/12/13/14

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When a no-load condition is detected MOP and MON are held low.

7.15

Configuring the STPM1X

All the configuration bits that control the operation of the device can be written temporarily or

permanently. For temporary writing, the configuration bits value are written in the Shadow

Registers which are simple latches that hold the configuration data. For permanent writing,

the configuration bits are stored in the OTP (one time programmable) cells that keep the

information for an undefined period of time even if the STPM1X is without supply, but, once

written, they cannot be changed. The temporary writing is useful mainly during testing of the

device or during the calibration phase. All the configuration parameters can be changed an

infinite number of times in order to test the device operation.

The shadow registers are cleared whenever a reset condition occurs.

The configuration bits are different for STPM11/12 and for STPM13/14 due to the presence

of the Tamper module. Each of them consists of paired elements, one is latch (the OTP

shadow), and one is the OTP anti-fuse element. When the STPM1X is released in the

market, all anti-fuses represent logic low state but they can be written by the user in order to

configure the STPM1X. This means that STPM1X can retain these bits of information even if

it has been unsupplied for an undefined time. That's why the CFG signals are used to keep

certain configuration and calibration values of the device.

Figure 19.

Positive energy or absolute computation energy (ABS=1) stepper driving signals

MON

MOP

Figure 20.

Negative energy stepper driving signals

MON

MOP

STPM12ATR Datasheet(PDF) 24 Page - STMicroelectronics