TC648 Microchip, TC648 Datasheet - Page 8

• Manufacturer Part Number: TC648
• Description: Fan Speed Controller
• Manufacturer: Microchip

TC648
FIGURE 4-1:
DS21448C-page 8
Power-Up
V
V
IN
OUT
> 1.25V
V
Power-Up
Power-on
V
No
OTF = 1
IN
No
AS
Yes
Reset
= 0
< V
OTF = 0
0V
AS
TC648 Behavioral Algorithm Flowcharts.
Yes
?
No
Yes
Yes
Yes
V
V
Speed Mode
V
V
OUT
IN
Shutdown
V
Minimum
IN
IN
OTF = 1
OUT
> 1.25V ?
Auto-
> V
Duty Cycle Proportional to V
0V ?
Speed Mode
Yes
No
No
OTF
= 0
Minimum
(V
Fire Start-up
Operation
AS
?
Normal
Timer
V
+ V
IN
>
HAS
YES
No
)
No
V
OUT
IN
= 0
Shutdown
V
OTF = 0
OUT
Auto-
2002 Microchip Technology Inc.
= 0
Yes
Yes
V
Cycle Prop.
V
Operation
V
No
No
OUT
OTF = 1
IN
Normal
IN
to V
> V
< V
IN
Duty
OTF
AS
?
?