ST16C654 EXAR [Exar Corporation], ST16C654 Datasheet - Page 7

• Manufacturer Part Number: ST16C654
• Description: 2.97V TO 5.5V QUAD UART WITH 64-BYTE FIFO
• Manufacturer: EXAR [Exar Corporation]

ST16C654/654D
2.97V TO 5.5V QUAD UART WITH 64-BYTE FIFO
REV. 5.0.0
Pin Description
Pin type: I=Input, O=Output, I/O= Input/output, OD=Output Open Drain.
ANCILLARY SIGNALS
(RESET#)
CHCCLK
CLKSEL
RESET
16/68#
XTAL1
XTAL2
N
RIC#
RID#
RIA#
RIB#
GND
VCC
N.C.
AME
64-TQFP
4, 35, 52
14, 28,
45, 61
P
63
19
30
50
25
26
27
21
IN
-
-
-
#
68-PLCC
6, 23, 40,
13, 47,
P
28
42
62
35
36
31
30
37
64
57
IN
8
-
-
#
100-QFP
1- 4, 26-
10, 61,
20, 46,
28, 29,
30, 51-
55, 77,
78, 79,
71, 96
P
98
33
48
84
40
41
36
35
42
43
86
80
IN
#
T
Pwr 2.97V to 5.5V power supply. The inputs are not 5V tolerant when
Pwr Power supply common, ground.
YPE
O
I
I
I
I
I
I
UART channels A-D Ring-Indicator (active low) or general purpose
input.
Crystal or external clock input.
Crystal or buffered clock output.
Intel or Motorola Bus Select (input with internal pull-up).
When 16/68# pin is at logic 1, 16 or Intel Mode, the device will oper-
ate in the Intel bus type of interface.
When 16/68# pin is at logic 0, 68 or Motorola mode, the device will
operate in the Motorola bus type of interface.
Motorola bus interface is not available on the 64 pin package.
Baud-Rate-Generator Input Clock Prescaler Select for channels A-
D. This input is only sampled during power up or a reset. Connect to
VCC for divide by 1 (default) and GND for divide by 4. MCR[7] can
override the state of this pin following a reset or initialization. See
MCR bit-7 and
This input provides the clock for UART channel C. An external 16X
baud clock or the crystal oscillator’s output, XTAL2, must be con-
nected to this pin for normal operation. This input may also be used
with MIDI (Musical Instrument Digital Interface) applications when
an external MIDI clock is provided. This pin is only available in the
100-pin QFP package.
When 16/68# pin is at logic 1 for Intel bus interface, this input
becomes the
Motorola bus interface is not available on the 64 pin package.
operating at 3.3V.
No Connection. These pins are not used in either the Intel or Motor-
ola bus modes. These pins are open, but typically, should be con-
nected to GND for good design practice.
7
Figure 6
in the Baud Rate Generator section.
D
ESCRIPTION