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