21 ELECTRICAL CHARACTERISTICS
21-4
Seiko Epson Corporation
S1C17M20/M21/M22/M23/M24/M25
TECHNICAL MANUAL (Rev. 1.0)
21.4 System Reset Controller (SRC) Characteristics
#RESET pin characteristics
Unless otherwise specified: V
DD
= 1.8 to 5.5 V, V
SS
= 0 V, Ta = -40 to 85
°
C
Item
Symbol
Condition
Min.
Typ.
Max.
Unit
High level Schmitt input threshold voltage V
T+
0.5
×
V
DD
–
0.8
×
V
DD
V
Low level Schmitt input threshold voltage V
T-
0.2
×
V
DD
–
0.5
×
V
DD
V
Schmitt input hysteresis voltage
D
V
T
180
–
–
mV
Input pull-up resistance
R
IN
100
230
500
k
W
Pin capacitance
C
IN
–
–
15
pF
Reset Low pulse width
t
SR
5
–
–
µs
#RESET
t
SR
V
T+
V
T-
POR/BOR characteristics
Unless otherwise specified: V
DD
= 1.8 to 5.5 V, V
SS
= 0 V, Ta = -40 to 85
°
C
Item
Symbol
Condition
Min.
Typ.
Max.
Unit
POR/BOR canceling voltage
V
RST+
1.41
–
1.75
V
POR/BOR detection voltage
V
RST-
1.25
–
1.55
V
POR/BOR hysteresis voltage
D
V
RST
40
60
–
mV
POR/BOR detection response time
t
RST
–
–
20
µs
POR/BOR operating limit voltage
V
RST
OP
–
0.5
0.95
V
POR/BOR reset request hold time
t
RRQ
0.01
–
4
ms
POR&BOR
reset request
V
DD
V
SS
V
RST
OP
V
RST-
V
RST-
V
RST-
V
RST+
Indefinite (operating limit)
POR/BOR reset request
t
RRQ
X
X
X
REQ
REQ
t
RRQ
REQ
t
RRQ
t
RST
t
RST
t
RST
X
V
RST
OP
V
RST
OP
V
RST+
REQ
∆
V
RST
Note: When performing a power-on-reset again after the power is turned off, decrease the V
DD
voltage
to V
RST
OP or less.
Reset hold circuit characteristics
Unless otherwise specified: V
DD
= 1.8 to 5.5 V, V
SS
= 0 V, Ta = -40 to 85
°
C
Item
Symbol
Condition
Min.
Typ.
Max.
Unit
Reset hold time
*
1
t
RSTR
0.5
–
1.7
ms
*
1 Time until the internal reset signal is negated after the reset request is canceled.
21.5 Clock Generator (CLG) Characteristics
Oscillator circuit characteristics including resonators change depending on conditions (board pattern, components
used, etc.). Use these characteristic values as a reference and perform matching evaluation using the actual printed
circuit board.
IOSC oscillator circuit characteristics
Unless otherwise specified: V
DD
= 1.8 to 5.5 V, V
SS
= 0 V, Ta = -40 to 85
°
C
Item
Symbol
Condition
Ta
Min.
Typ.
Max.
Unit
Oscillation start time
t
sta
I
–
–
3
µs
Oscillation frequency
f
IOSC
25
°
C
679
700
721
kHz
-40 to 85
°
C
651
700
749
kHz