Datasheet

Section 26 Electrical Characteristics
Page 1304 of 1408 R01UH0309EJ0500 Rev. 5.00
Sep 24, 2012
H8S/2456, H8S/2456R, H8S/2454 Group
Table 26.14 USB PLL Characteristics
Conditions: V
CC
= 3.0 V to 3.6 V, AV
CC
= 3.0 V to 3.6, V
ref
= 3.0 V to AV
CC
,
V
SS
= AV
SS
= 0V, EXTAL = 8 to 16 MHz
Item Symbol Min Max Unit Test Conditions
PLL for USB: oscillation
stabilization time
t
USOSC
1 ⎯ ms Figure 26.38
26.1.7 Flash Memory Characteristics
Table 26.15 Flash Memory Characteristics
Conditions: V
CC
= 3.0 to 3.6V, AV
CC
= 3.0 to 3.6V, V
ref
= 3.0 V to AV
CC
, V
SS
= AV
SS
= 0V,
φ = 8 MHz to 33 MHz
Standard value
Item Applicable area
Min. Typ. Max. Unit
User ROM 1000*
2
⎯ ⎯ Programming and erase count*
1
Data flash area 10000*
2
⎯ ⎯
Times
User ROM ⎯ 150 4000 Programming time
(per 4 bytes)
Data flash area ⎯ 300 4000
μs
User ROM ⎯ 300 3000 Erase time (per 1 block)
Data flash area ⎯ 300 3000
ms
User ROM 3.0 Programming and erase voltage
Data flash area
⎯ 3.6 V
User ROM Read voltage
Data flash area
3.0 ⎯ 3.6 V
User ROM 1 ⎯ ⎯ Access state
Data flash area 2 ⎯ ⎯
State
Notes: 1. When programming is to be performed multiple times on a system, reduce the effective number of
programming operations by shifting the writing addresses in sequence and so on until the
remaining blank area is as small as possible and only then erasing the entire block once. For
example, if sets of 16 bytes are being programmed, erasing the block once after programming the
maximum number of sets (256) minimizes the effective number of programming operations.
We recommend keeping information on the number of times erasure is performed for each block,
and setting up the limit on the number of times.
2. If an erase error occurs during erasure, execute the clear status command and then the erase
command at least 3 times until the erase does not recur.