TEA3718DP datasheet(14/26 Pages) STMICROELECTRONICS

Numer części	TEA3718DP

Szczegółowy opis	Stepper motor driver

PDF	26 Pages

Scroll/Zoom	100%

Producent	STMICROELECTRONICS [STMicroelectronics]

Strona internetowa	http://www.st.com

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Functional blocks

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4.1

Alarm output (TEA3718SP, TEA3718DP and TEA3718SDP)

The ALARM output pin becomes low when the junction temperature reaches T

° C. When an

alarm condition occurs, parts of the supply voltage (dividing bridge R - RC) is fed to the

comparator input pin (

Figure 16). Depending on the RC value the behavior of the circuit on

an alarm condition is as follows:

●

RC > 80 ohms, the output stage is switched off

●

RC > 60 ohms, the current in the motor windings is reduced according to the

approximate formula: (see also

Figure 18 and Figure 19)

with VTH = threshold of the comparator (VCH, VCM, VCL) R = 700 ohms (typical).

For several Multiwatt packages a common detection can be obtained as in

Figure 17.

Figure 16.

Alarm detection for power DIP package

VTH

----------

VCC

RRC

------------------

--------

•

–

TEA3718DP Arkusz danych(PDF) 14 Page - STMicroelectronics