Datasheet

Section 19 Band-Gap Circuit, Power-On Reset, and Low-Voltage Detection Circuits
Rev. 3.00 Sep. 10, 2007 Page 381 of 528
REJ09B0216-0300
φ
RES
CRES
CK
R
PSS
VBGR
ExtU
ExtD
VDDII
Vcc
R
S
Q
OVF
Vreset
VintD
VintU
LVDRES
LVDCR
LVDSR
LVDINT
[Legend]
PSS: Prescaler S
LVDCR: Low-voltage-detection control register
LVDSR: Low-voltage-detection status register
VBGR: Reference voltage from BGR
ExtD: Compared voltage for falling external input voltage
ExtU: Compared voltage for rising external input voltage
VDDII: Bit 5 in LVDCR
Noise filter
circuit
Noise filter
circuit
Internal
reset signal
Power-on reset circuit
Interrupt
control
circuit
Internal data bus
Interrupt request
Ladder
network
External
power
supply
150 kΩ
Figure 19.2 Block Diagram of Power-On Reset Circuit and Low-Voltage Detection Circuit