UPD784907 Datasheet, PDF (77/98 Pages) NEC – 16-BIT SINGLE-CHIP MICROCONTROLLER

µPD784907, 784908
(3) Bus hold timing
Parameter
Delay from HLDRQ↑ to float
Delay from HLDRQ↑ to HLDAK↑
Delay from float to HLDAK↑
Delay from HLDRQ↓ to HLDAK↓
Delay from HLDRQ↓ to active
Symbol
tFQHC
tDHQHHAH
tDCFHA
tDHQLHAL
tDHAC
VDD = 5.0 V
VDD = 5.0 V
VDD = 5.0 V
VDD = 5.0 V
VDD = 5.0 V
Conditions
(2 + 4 + a + n)T + 50
(3 + 4 + a + n)T + 30
T + 30
2T + 40
T – 20
Remark T: tCYK (system clock cycle time) VDD = 5.0 V T = 79 ns (MIN.)
a: 1 during address wait, otherwise, 0
n: number of wait states (n ≥ 0)
(4) Refresh timing
Parameter
Random read/write cycle time
REFRQ low-level pulse width
Delay from ASTB↓ to REFRQ
Delay from RD↑ to REFRQ
Delay from WR↑ to REFRQ
Delay from REFRQ↑ to ASTB
REFRQ high-level pulse width
Symbol
tRC
tWRFQL
tDSTRFQ
tDRRFQ
tDWRFQ
tDRFQST
tWRFQH
VDD = 5.0 V
VDD = 5.0 V
VDD = 5.0 V
VDD = 5.0 V
VDD = 5.0 V
VDD = 5.0 V
VDD = 5.0 V
Conditions
3T
1.5T – 25
0.5T – 9
1.5T – 9
1.5T – 9
0.5T – 9
1.5T – 25
Remark T: tCYK (system clock cycle time) VDD = 5.0 V T = 79 ns (MIN.)
MIN.
MAX.
Unit
765
ns
825
ns
109
ns
199
ns
59
ns
MIN.
MAX.
Unit
238
ns
94
ns
31
ns
110
ns
110
ns
31
ns
94
ns
Data Sheet U11680EJ2V0DS00
77