beautypg.com

Circuit – FUJITSU F2MCTM-16LX User Manual

Page 390

background image

374

CHAPTER 19 LOW VOLTAGE DETECTION/CPU OPERATING DETECTION RESET

19.2

Configuration of Low Voltage/CPU Operating Detection
Reset Circuit

Low voltage/CPU operating detection reset circuit has following three blocks.
• CPU operating detection circuit
• Voltage comparison circuit
• Low voltage/CPU operating detection reset control register (LVRC)

Block Diagram of Low Voltage/CPU Operating Detection Reset Circuit

Figure 19.2-1 Block Diagram of Low Voltage/CPU operating Detection Reset Circuit

V

CC

-
+

V

SS

Voltage comparison
circuit

Counter

F/ F

CPU operating detection circuit

Oscillation clock

Reserved Reserved Reserved Reserved

CL

LVRF

Reserved

CPUF

Low voltage/CPU operating detection
reset control register (LVRC)

Clear

OF

Internal data bus

Fixed voltage supply

Internal reset

Noise canceler