IC MPU 16BIT 5V 20MHZ 68PLCC

EE80C188XL20

Manufacturer Part NumberEE80C188XL20
DescriptionIC MPU 16BIT 5V 20MHZ 68PLCC
ManufacturerIntel
EE80C188XL20 datasheet
 


Specifications of EE80C188XL20

Processor Type80C186FeaturesXL suffix, 16-Bit
Speed20MHzVoltage5V
Mounting TypeSurface MountPackage / Case68-PLCC
Family NameIntel186Device Core80188
Device Core Size16bFrequency (max)20MHz
Instruction Set ArchitectureCISCSupply Voltage 1 (typ)5V
Operating Supply Voltage (max)5.5VOperating Supply Voltage (min)4.5V
Operating Temp Range0C to 70COperating Temperature ClassificationCommercial
MountingSurface MountPin Count68
Package TypePLCCLead Free Status / RoHS StatusLead free / RoHS Compliant
Other names863554  
1
Page 1
2
Page 2
3
Page 3
4
Page 4
5
Page 5
6
Page 6
7
Page 7
8
Page 8
9
Page 9
10
Page 10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
Page 7/48

Download datasheet (401Kb)Embed
PrevNext
DRAM Refresh Control Unit
The Refresh Control Unit (RCU) automatically gen-
erates DRAM refresh bus cycles The RCU operates
only in Enhanced Mode After a programmable peri-
od of time the RCU generates a memory read re-
quest to the BIU If the address generated during a
refresh bus cycle is within the range of a properly
programmed chip select that chip select will be acti-
vated when the BIU executes the refresh bus cycle
Power-Save Control
The 80C186XL when in Enhanced Mode can enter
a power saving state by internally dividing the proc-
essor clock frequency by a programmable factor
This divided frequency is also available at the
CLKOUT pin
All internal logic including the Refresh Control Unit
and the timers have their clocks slowed down by
the division factor To maintain a real time count or a
fixed DRAM refresh rate these peripherals must be
re-programmed when entering and leaving the pow-
er-save mode
Interface for 80C187 Math
Coprocessor (80C186XL Only)
In Enhanced Mode three of the mid-range memory
chip selects are redefined according to Table 1 for
use with the 80C187 The fourth chip select MCS2
80C186XL 80C188XL
functions as in compatible mode and may be pro-
grammed for activity with ready logic and wait states
accordingly As in Compatible Mode MCS2 will func-
tion for one-fourth a programmed block size
Table 1 MCS Assignments
Compatible
Enhanced Mode
Mode
MCS0
PEREQ Processor Extension Request
MCS1
ERROR NPX Error
MCS2
MCS2
Mid-Range Chip Select
MCS3
NPS
Numeric Processor Select
ONCE Test Mode
To facilitate testing and inspection of devices when
fixed into a target system the 80C186XL has a test
mode available which allows all pins to be placed in
a high-impedance state ONCE stands for ‘‘ON Cir-
cuit Emulation’’ When placed in this mode the
80C186XL will put all pins in the high-impedance
state until RESET
The ONCE mode is selected by tying the UCS and
the LCS LOW during RESET These pins are sam-
pled on the low-to-high transition of the RES pin
The UCS and the LCS pins have weak internal pull-
up resistors similar to the RD and TEST BUSY pins
to guarantee ONCE Mode is not entered inadver-
tently during normal operation LCS and UCS must
be held low at least one clock after RES goes high
to guarantee entrance into ONCE Mode
7