CHAPTER 22 ELECTRICAL SPECIFICATIONS (
µ
PD789488, 78F9488, 789489, 78F9489)
User’s Manual U15331EJ4V1UD
353
(2) Serial interface 20 (SIO20) (T
A
= –40 to +85
°
C, V
DD
= 1.8 to 5.5 V)
(a) 3-wire serial I/O mode (internal clock output)
Parameter Symbol
Conditions
MIN.
TYP.
MAX.
Unit
V
DD
= 2.7 to 5.5 V
800
ns
SCK20 cycle time
t
KCY1
V
DD
= 1.8 to 5.5 V
3200
ns
V
DD
= 2.7 to 5.5 V
t
KCY1
/2–50
ns
SCK20 high-/low-level
width
t
KH1
,
t
KL1
V
DD
= 1.8 to 5.5 V
t
KCY1
/2–150
ns
V
DD
= 2.7 to 5.5 V
150
ns
SI20 setup time
(to SCK20
↑
)
t
SIK1
V
DD
= 1.8 to 5.5 V
500
ns
V
DD
= 2.7 to 5.5 V
400
ns
SI20 hold time
(from SCK20
↑
)
t
KSI1
V
DD
= 1.8 to 5.5 V
600
ns
V
DD
= 2.7 to 5.5 V
0
250
ns
Delay time from SCK20
↓
to SO20 output
t
KSO1
R = 1 k
Ω
, C = 100 pF
Note
V
DD
= 1.8 to 5.5 V
0
1000
ns
Note
R and C are the load resistance and load capacitance of the SO20 output line.
(b) 3-wire serial I/O mode (external clock input)
Parameter Symbol
Conditions
MIN.
TYP.
MAX.
Unit
V
DD
= 2.7 to 5.5 V
800
ns
SCK20 cycle time
t
KCY2
V
DD
= 1.8 to 5.5 V
3200
ns
V
DD
= 2.7 to 5.5 V
400
ns
SCK20 high-/low-level
width
t
KH2
,
t
KL2
V
DD
= 1.8 to 5.5 V
1600
ns
V
DD
= 2.7 to 5.5 V
100
ns
SI20 setup time
(to SCK20
↑
)
t
SIK2
V
DD
= 1.8 to 5.5 V
150
ns
V
DD
= 2.7 to 5.5 V
400
ns
SI20 hold time
(from SCK20
↑
)
t
KSI2
V
DD
= 1.8 to 5.5 V
600
ns
V
DD
= 2.7 to 5.5 V
0
300
ns
Delay time from SCK20
↓
to SO20 output
t
KSO2
R = 1 k
Ω
, C = 100 pF
Note
V
DD
= 1.8 to 5.5 V
0
1000
ns
Note
R and C are the load resistance and load capacitance of the SO20 output line.
(c) UART mode (dedicated baud rate generator output)
Parameter Symbol
Conditions
MIN.
TYP.
MAX.
Unit
V
DD
= 2.7 to 5.5 V
78125
bps
Transfer rate
V
DD
= 1.8 to 5.5 V
19531
bps