Specifications

178
3706C–MICRO–2/11
AT89LP3240/6440
26.6 Reset Characteristics
The values shown in this table are valid for T
A
= -40°C to 85°C and V
DD
= 2.4 to 3.6V, unless otherwise noted.
26.7 External Data Memory Characteristics
The values shown in this table are valid for T
A
= -40°C to 85°C and V
DD
= 2.4 to 3.6V, unless otherwise noted. Under oper-
ating conditions, load capacitance for Port 0 and ALE = 100 pF; load capacitance for all other outputs = 80 pF. Parameters
refer to Figure 26-15 and Figure 26-16.
Notes:1.This assumes 50% clock duty cycle. The half period depends on the clock high value t
CHCX
(high duty cycle).
2. This assumes 50% clock duty cycle. The half period depends on the clock low value t
CLCX
(low duty cycle).
Table 26-3. Reset Characteristics
Symbol Parameter Condition Min Max Units
R
RST
Reset Pull-up Resistor 50 150 kΩ
V
POR
Power-On Reset Threshold 1.3 1.6 V
V
BOD
Brown-Out Detector Threshold 1.8 2.0 V
V
BH
Brown-Out Detector Hysteresis 200 300 mV
t
POR
Power-On Reset Delay 135 150 µs
t
WDTRST
Watchdog Reset Pulse Width 16t
CLCL
ns
Table 26-4. External Data Memory Characteristics
Symbol Parameter
Variable Oscillator
UnitsMin Max
1/t
CLCL
Oscillator Frequency 0 24 MHz
t
LHLL
ALE Pulse Width
(3)
t
CLCL
- d ns
t
AVLL
Address Valid to ALE Low 0.5t
CLCL
- d
(1)
ns
t
LLAX
Address Hold after ALE Low 0.5t
CLCL
- d
(2)
ns
t
RLRH
RD Pulse Width
(4)
t
CLCL
- d ns
t
WLWH
WR Pulse Width
(4)
t
CLCL
- d ns
t
RLDV
RD Low to Valid Data In t
CLCL
- d ns
t
RHDX
Data Hold after RD 0ns
t
RHDZ
Data Float after RD t
CLCL
- d ns
t
LLDV
ALE Low to Valid Data In 2t
CLCL
- d ns
t
AVDV
Address to Valid Data In 2.5t
CLCL
- d
(1)
ns
t
LLWL
ALE Low to RD or WR Low t
CLCL
- d t
CLCL
+ d ns
t
AVWL
Address to RD or WR Low 1.5t
CLCL
- d
(1)
ns
t
QVWX
Data Valid to WR Transition 0.5t
CLCL
- d
(1)
ns
t
QVWH
Data Valid to WR High 1.5t
CLCL
- d
(1)
ns
t
WHQX
Data Hold after WR 0.5t
CLCL
- d
(2)
ns
t
RLAZ
RD Low to Address Float -0.5t
CLCL
+ d
(1)
ns
t
WHAX
Address Hold after RD or WR High 0.5t
CLCL
- d
(2)
ns
t
WHLH
RD or WR High to ALE High
(5)
t
CLCL
- d t
CLCL
+ d ns