CD1865 Datasheet, PDF (15/150 Pages) Intel Corporation – Intelligent Eight-Channel Communications Controller

Intelligent Eight-Channel Communications Controller — CD1865
3.0
Device Selection Considerations
The CD1865 device is an enhanced version of the same product family as the CD180 and CD1864.
The CD1865 is software compatible with both the CD180 and CD1864. If this is a new CD1865
design, please skip this page.
The CD1865 is recommended for any new designs. Please note that to achieve the high data rates,
66-MHz system clock is required. To support data rates of up to 115.2 kbps, the specified system
clock frequency is required. Please refer to the differences in pins between the CD1864 and
CD1865. It is recommended that the 66-MHz, 2×-clock option (oscillator or crystal) is used
wherever possible.
Table 1. CD18XX Product Family
Features
Package
System clock
Maximum bit rates
Pins
CD180
CD1864
CD1865
84-pin PLCC
12.5 MHz
64 kbps
DTRSEL *
4 modem/IO signals per
channel
100-pin PQFP
25 MHz (×2) or
12.5 MHz (×1)
64 kbps
–
5 modem/IO signals per
channel
100-pin MQFP
66 MHz (×2) or
33 MHz (×1)
115.2 kbps
–
5 modem/IO signals per
channel
Note: This input (DTRSEL) on the CD180 sets the mode for the DTR*/CD* pins. When DTRSEL is
high, the DTR*/CD* pins implement the DTR* output; when low, the DTR*/CD* pins become
CD* inputs.
The CD1864 and CD1865 have separate DTR and CD pins and so the DTRSEL is eliminated.
Table 2. Differences Between the CD1865 and CD1864
Pin Number
CD1865
Pin Name
CD1864
Pin Name
Comments
1
V_CC
n/c
Note 1
16
GND
n/c
Note 1
37
V_CC
n/c
Note 2
NOTES:
1. Pin 1 and pin 16 are truly no-connects on the CD1864 device.
2. Pin 37 on the CD1864 is not a true no-connect, and can cause problems if connected to V_CC. To make a
single board design be compatible with either the CD1864 or CD1865, a configuration jumper must be used
to allow pin 37 to be a no-connect or a V_CC connection.
Note: In January 1995, Intel changed all 100-pin PQFP package types from EIAJ to JEDEC. The
CD1865 is now available in a JEDEC package. Before beginning any new design or converting
from CD1864 to CD1865, please contact Intel for package details.
Warning: The CD1865 device may have potential latch up problems if used in socket. It is recommended that
this device be surface mounted.
Datasheet
15