STMPE2401TBR STMicroelectronics, STMPE2401TBR Datasheet - Page 47

• Manufacturer Part Number: STMPE2401TBR
• Description: IC I/O EXPANDER I2C 24B 36TFBGA
• Manufacturer: STMicroelectronics

Specifications of STMPE2401TBR

• Interface: I²C
• Number Of I /o: 24
• Interrupt Output: Yes
• Frequency - Clock: 400kHz
• Voltage - Supply: 1.65 V ~ 1.95 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 36-TFBGA
• Includes: Keypad, POR, PWM
• For Use With: 497-6426 - BOARD EVAL BASED ON STMPE2401
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6133-2

STMPE2401
14
Rotator controller
Rotator controller consists of 3 terminal, each capable of becoming an input with internal
pull-up, or and output. At any moment, 2 terminals are inputs and one terminal is output.
Figure 10. Rotator controller
The Rotator Controller is responsible for the detection of the direction of rotator and the
reporting of these direction sequences. The direction of a rotator can be either up or down.
A rotator has 3 contacts and detection of shorts on these contacts is used to determine the
direction of rotation. Following diagram shows the definition of the direction of rotation and
how the FSM states and driven outputs correspond to rotation.
Table 46. 3 possible conditions: A-B short, B-C short, C-A short.
Figure 11. Possible conditions
Input
LO
C
B
A
C
A
B
State
1
1
2
2
3
3
Output
Current State
A
A
B
B
C
C
Input
B
B
A
A
A
A
Input
C
C
C
C
B
B
State
2
3
3
1
2
1
Output
C
C
B
A
B
A
Next State
Input
A
A
A
B
A
B
Rotator controller
Input
C
C
C
C
B
B
Result
Down
Down
Down
Up
Up
Up
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