XR16V654_0709 Datasheet, PDF (10/58 Pages) Exar Corporation – 2.25V TO 3.6V QUAD UART WITH 64-BYTE FIFO

XR16V654/654D
2.25V TO 3.6V QUAD UART WITH 64-BYTE FIFO
Pin Description
REV. 1.0.2
NAME
48-QFN
PIN #
64-LQFP 68-PLCC 80-LQFP 100-QFP
PIN #
PIN#
PIN #
PIN #
TYPE
DESCRIPTION
RESET
20
27
37
33
43
I When 16/68# pin is HIGH for Intel bus inter-
(RESET#)
face, this input becomes the Reset pin
(active high). In this case, a 40 ns mini-
mum HIGH pulse on this pin will reset the
internal registers and all outputs. The UART
transmitter output will be held HIGH, the
receiver input will be ignored and outputs
are reset during reset period (Table 17).
When 16/68# pin is at LOW for Motorola
bus interface, this input becomes Reset#
pin (active low). This pin functions similarly,
but instead of a HIGH pulse, a 40 ns mini-
mum LOW pulse will reset the internal reg-
isters and outputs.
Motorola bus interface is not available on
the 64 pin package.
VCC
2, 24, 37 4, 35, 52 13, 47, 6, 46, 66 10, 61, Pwr 2.25V to 3.6V power supply. All inputs,
64
86
except XTAL1, are 5V tolerant.
GND
GND
21, 47
Center
Pad
14, 28,
45, 61
N/A
6, 23, 40,
57
N/A
16, 36,
56, 76
N/A
20, 46, Pwr Power supply common, ground.
71, 96
N/A _{Pwr The center pad on the backside of the QFN}
package is metallic and should be con-
nected to GND on the PCB. The thermal
pad size on the PCB should be the approxi-
mate size of this center pad and should be
solder mask defined. The solder mask
opening should be at least 0.0025" inwards
from the edge of the PCB thermal pad.
N.C.
-
-
-
1, 2, 20,
21, 22,
27, 40,
41, 42,
60, 61,
62, 80
No Connection. These pins are not used in
either the Intel or Motorola bus modes.
Pin type: I=Input, O=Output, I/O= Input/output, OD=Output Open Drain.
10