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CHAPTER 29 ELECTRICAL SPECIFICATIONS ((A) GRADE PRODUCTS)
User’s Manual U17893EJ8V0UD
816
(A) Grade Products
(2) Serial interface: Serial array unit (8/18)
(TA =
40 to +85°C, 2.7 V ≤ VDD = EVDD ≤ 5.5 V, VSS = EVSS = AVSS = 0 V)
(e) Communication at different potential (2.5 V, 3 V) (UART mode) (dedicated baud rate generator output) (2/2)
Parameter
Symbol
Conditions
MIN.
TYP.
MAX.
Unit
Note 1
4.0 V
≤ VDD ≤ 5.5 V,
2.7 V
≤ Vb ≤ 4.0 V
fCLK = 16.8 MHz, fMCK = fCLK,
Cb = 50 pF, Rb = 1.4 k
Ω, Vb = 2.7 V
2.8
Note 2
Mbps
Note 3
Transfer rate
transmission
2.7 V
≤ VDD < 4.0 V,
2.3 V
≤ Vb ≤ 2.7 V
fCLK = 19.2 MHz, fMCK = fCLK,
Cb = 50 pF, Rb = 2.7 k
Ω, Vb = 2.3 V
1.2
Note 4
Mbps
Notes 1.
The smaller maximum transfer rate derived by using fMCK/6 or the following expression is the valid
maximum transfer rate.
Expression for calculating the transfer rate when 4.0 V
≤ VDD = EVDD ≤ 5.5 V and 2.7 V ≤ Vb ≤ 4.0 V
1
Maximum transfer rate =
[bps]
{
Cb × Rb × ln (1
2.2
Vb
)} × 3
1
Transfer rate
× 2 {C
b
× Rb × ln (1
2.2
Vb
)}
Baud rate error (theoretical value) =
× 100 [%]
(
1
Transfer rate
) × Number of transferred bits
* This value is the theoretical value of the relative difference between the transmission and reception sides.
2.
This value as an example is calculated when the conditions described in the “Conditions” column are met.
Refer to Note 1 above to calculate the maximum transfer rate under conditions of the customer.
3.
The smaller maximum transfer rate derived by using fMCK/6 or the following expression is the valid
maximum transfer rate.
Expression for calculating the transfer rate when 2.7 V
≤ VDD = EVDD < 4.0 V and 2.3 V ≤ Vb ≤ 2.7 V
1
Maximum transfer rate =
{
Cb × Rb × ln (1
2.0
Vb
)} × 3
[bps]
1
Transfer rate
× 2 {C
b
× Rb × ln (1
2.0
Vb
)}
Baud rate error (theoretical value) =
× 100 [%]
(
1
Transfer rate
) × Number of transferred bits
* This value is the theoretical value of the relative difference between the transmission and reception sides.
4.
This value as an example is calculated when the conditions described in the “Conditions” column are met.
Refer to Note 3 above to calculate the maximum transfer rate under conditions of the customer.
Caution
Select the TTL input buffer for RxDq and the N-ch open drain output (VDD tolerance) mode for TxDq
by using the PIMg and POMg registers.
(Remark are given on the next page.)