STK672-400C-E

No.A2136-9/19

Usage Notes

1. Input pins and functional overview

[Input pins]

Hybrid IC pin No.

Symbol

Function

Pin type

19

Vref

Current setting

Input impedance: 200k

Ω (typical)

10, 11, 17

MODE1, MODE2, MODE3

Excitation mode setting

TTL level Schmitt input

12

CLK

Phase switching clock

(speed command)

Same as the above

13

CWB

Motor direction setting

Same as the above

14

RESET

System reset

Same as the above

15

ENABLE

Motor current off

Same as the above

2. Input signal functions

[CLK (Phase switching clock)]

(1) Input frequency: DC to 50kHz

(2) Minimum pulse width: 10

μs

(3) Pulse width duty: 40 to 60%

(4) Pin circuit type: TTL level Schmitt trigger input

(5) A multi-stage noise exclusion circuit is included.

(6) Function

• M3:1

When M3 is 1:The excitation phase is advanced one step on each CLK signal rising edge.

• M3:0

When M3 is 0:The excitation phase is advanced one step alternately on each CLK signal rising or falling edge.

• Timing chart

[CWB (Motor direction setting)]

(1) Pin circuit type: TTL level Schmitt trigger input

(2) Function

• When CWB = 0: The motor turns in the clockwise direction

• When CWB = 1: The motor turns in the counterclockwise direction

(3) Note: The value of the CWB input must not be changed in the period from 7

μs before a CLK input rising or falling

edge until 7

μs after that edge.

[ENABLE (Forces the excitation drive outputs A, AB, B, and BB to the off state and selects the hybrid IC's internal

state to be operating or hold)]

(1) Pin circuit type: TTL level Schmitt trigger input

(2) Function

a) When ENABLE is 1: Normal operating state

b) When ENABLE is 0: The motor current is turned off and the excitation drive output is turned off forcibly. At

this time, the hybrid IC's system clock is stopped and the hybrid IC is not influenced by

changes to any input pins other than the reset input.

Excitation counter up/down

CLK input

System clock

Phase excitation

counter clock

Control output timing

Control output switching timing