DS87C550-QNL Maxim Integrated Products, DS87C550-QNL Datasheet - Page 37

• Manufacturer Part Number: DS87C550-QNL
• Description: IC MCU EPROM ADC/PWM HS 68-PLCC
• Manufacturer: Maxim Integrated Products
• Series: 87Cr

Specifications of DS87C550-QNL

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 33MHz
• Connectivity: EBI/EMI, SIO, UART/USART
• Peripherals: Power-Fail Reset, PWM, WDT
• Number Of I /o: 55
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: OTP
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 6x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 68-LCC, 68-PLCC
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

AC ELECTRICAL CHARACTERISTICS
NOTES FOR AC ELECTRICAL CHARACTERISTICS
§
§
§
§
§
PARAMETER
Oscillator Freq. (Ext. Osc.)
ALE Pulse Width
Port 0 Address Valid to ALE Low
Address Hold after ALE Low
ALE Low to Valid Instruction In
ALE Low to PSEN Low
Input Instruction Hold after PSEN
Input Instruction Float after PSEN
Port 0 Address to Valid Instruction
In
Port 2 Address to Valid Instruction
In
PSEN Pulse Width
PSEN Low to Valid Instruction In
PSEN Low to Address Float
t
highlighted in the table “STRETCH VALUE TIMING” for all possible settings of the 4X/
The default condition is CD1 = 1 and CD0 = 0, where 4X/
All parameters apply to both commercial and industrial temperature operation unless otherwise noted.
Electrical characterizations are not 100% tested but are guaranteed by design and characterization.
All signals characterized with load capacitance of 80 pF except Port 0, ALE,
pF.
Interfacing to memory devices with float times (turn off times) over 25 ns may cause contention. This will not
damage the parts, but will cause an increase in operating current.
Specifications assume a 50% duty cycle for the oscillator. Port 2 and ALE timing will change in relation to
duty cycle variation.
MCS
is a time period related to the machine cycle clock and the processor’s input clock frequency. Its value is
(Ext. Crystal)
SYMBOL
1/t
t
t
t
t
t
t
t
t
LLAX1
t
t
t
t
AVIV2
LHLL
AVLL
AVIV
PLAZ
LLPL
PLPH
PXIX
LLIV
PLIV
PXIZ
CLCL
37 of 49
MIN
40
10
10
55
26
77
81
0
1
9
0
0
33MHz
2X
MAX
33
33
60
41
is disregarded.
0.375 t
0.125 t
0.125 t
0.125 t
0.5 t
VARIABLE CLOCK
MIN
MCS
0
1
0
MCS
MCS
MCS
MCS
PSEN
-5
-5
-5
-5
-5
,
0.25t
RD
0.75t
t
t
0.5t
MCS
MCS
MAX
0.625
0.875
-20
33
33
20
2X
0
MCS
and
MCS
MCS
-20
-25
and CD1:0 bits.
-5
-
WR
UNITS
with 100
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns