L6238 datasheet(31/35 Pages) STMICROELECTRONICS

31 / 35 page

Table 5: Control Register.

Ctrl

Bit #

Signal

Name

Control Function Description

Log ic

Default

State

Ext/Int

Determines whether the once-per-

revolution signal (used as the motor’s

feedback for speed) comes from internally

generated source or is to be supplied

externally as an input.

0 = Use Int

Speed Fdbk

1 = Use Ext

Speed Fdbk

Fref Enable

When enabled, passes external PLL fref to

Phase Detector

0 = Enable

1 = Disable

Lock_

Thrsh_0

Two bits that set the Lock Signal threshold

in the Phase Detector

Refer to Table 7

Lock_

Thrsh_1

Linear

Not used.

0 = Required

Out_Ena

Enables Output Drivers. When this signal is

used to Tri-State the outputs, it also resets

the resynchronization algorithm.

This bit along with the OUTPUT ENABLE

pin forms a logical AND function.

0 = Enable

1 = Disable

Run/Brake

When brought high, initiates the Align and

Go algorithm. When low, Brake action

occurs after the Brake Delay Timeout.

This bit along with the RUN/BRAKE pin

forms a logical AND function.

1 = Run

0 = Brake

Seq_Reset

Resets the sequencer to Phase 1. Reset

when in Brake Mode.

1 = Reset

0 = Normal

Auto/Ext

Selects either the Internal Auto Start-Up or

External Algorithm.

1 = Auto

0 = External

Seq_Incr

Increments sequencer

1 = Mask Bemf

0 = Normal

Phase_

Delay_0

Three bits that set the Delay between the

detection of the Bemf zero crossing and

the commutation to the next phase.

Refer to Table 6

Phase_

Delay_1

Phase_

Delay_2

Auto_Str_

Dly_0

These 2 Bits define 4 possible delayes for

Auto Start-Up Algorithm.

Refer to Table 8

Auto_Str_

Dly_1

Ilim_Gain

Programs the I Limit for either the value set

by ILIM SET or /2

0 = Ilimit

1 = Ilimit/2

L6238

31/35

L6238 Datasheet(PDF) 31 Page - STMicroelectronics

L6238 Datasheet(HTML) 31 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

Datasheet Download

Link URL