
Rev. 1.00
�� of ���
�an�a�� 1�� �01�
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
D.C. Characteristics
A.C. Characteristics
9
A.C. Characteristics
Ta=��°C
Symbol
Parameter
Test Conditions
Min.
Typ.
Max. Unit
V
DD
Conditions
f
SYS1
S�stem clock (C��stal OSC)
�.�V~�.�V
PLL Disable
0.4
—
8
MHz
�.7V~�.�V
0.4
—
1�
4.�V~�.�V
0.4
—
�4
f
SYS�
S�stem clock (PLL)
4.�V~�.�V C��stal OSC=4MHz� PLL Enable
4
—
3�
MHz
f
LIRC
3�kHz Inte�nal RC oscillato�
�V
Ta=��°C
-10%
3�
+10%
kHz
�.�V~�.�V Ta=-40°C~8�°C
-�0%
3�
+60%
f
HIRC
3.6864MHz Inte�nal RC oscillato�
3V
Ta=��°C
-3% 3.6864 +3%
MHz
�V
Ta=��°C
-3% 3.6864 +3%
f
TIMER
Time� Inp�t F�eq�enc� (T0~T3)
�.�V~�.�V f
SYS
=8MHz
0
—
�
MHz
�.7V~�.�V f
SYS
=1�MHz
0
—
3
4.�V~�.�V f
SYS
=�4MHz
0
—
6
t
RES
Exte�nal Reset Minim�m Low P�lse width
—
—
1
3.3
�
μs
t
SST
S�stem sta�t-�p time� pe�iod (Powe�-�p o�
wake-�p f�om Powe�-Down mode when
the main oscillato� is off o� s�stem clock is
switching between HXT and HIRC)
—
f
SYS
=HXT o� HIRC
—
10�4
—
t
SYS
t
RSTD
S�stem Reset Dela� Time (LVR �eset)
—
—
16
3�
64
ms
t
SRESET
Softwa�e Reset Width to Reset
—
—
4�
90
1�0
μs
t
HTO
HIRC T��n On Pe�iod
�.�V~�.�V HIRC OFF
→
ON
—
�00
—
μs
t
INT
Exte�nal Inte���pt Minim�m P�lse Width
—
MCU is in No�mal mode o� Idle
mode
—
4
—
t
SYS
t
LVR
Low Voltage Width to Reset
—
—
1�0
�40
480
μs