xr16v2651im Exar Corporation, xr16v2651im Datasheet - Page 6

• Manufacturer Part Number: xr16v2651im
• Description: High Performance Duart With 32-byte Fifo And Powersave
• Manufacturer: Exar Corporation

Pin Description
XR16V2651
HIGH PERFORMANCE DUART WITH 32-BYTE FIFO AND POWERSAVE FEATURE
Pin type: I=Input, O=Output, I/O= Input/output, OD=Output Open Drain.
(RESET#)
CLKSEL
RESET
16/68#
N
GND
GND
VCC
NC
AME
32-QFN
Center
P
Pad
17
24
26
13
IN
-
-
#
48-TQFP
P
N/A
24
25
36
42
17
37
IN
#
T
Pwr 2.25V to 3.6V power supply. All input pins are 5V tolerant.
Pwr Power supply common, ground.
Pwr The center pad on the backside of the 32-QFN package is metallic and should be
YPE
-
I
I
I
Intel or Motorola Bus Select.
When 16/68# pin is HIGH, 16 or Intel Mode, the device will operate in the Intel bus
type of interface.
When 16/68# pin is LOW, 68 or Motorola mode, the device will operate in the
Motorola bus type of interface.
Baud-Rate-Generator Input Clock Prescaler Select for channel A and B. This input
is only sampled during power up or a reset. Connect to VCC for divide by 1 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
When 16/68# pin is HIGH for Intel bus interface, this input becomes RESET (active
high). When 16/68# pin is LOW for Motorola bus interface, this input becomes
RESET# (active low).
A 40 ns minimum active pulse on this pin will reset the internal registers and all out-
puts of channel A and B. The UART transmitter output will be held HIGH, the
receiver input will be ignored and outputs are reset during reset period (see
Table 16).
connected to GND on the PCB. The thermal pad size on the PCB should be the
approximate 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 ther-
mal pad.
No connection.
6
Figure 5
D
ESCRIPTION
in the Baud Rate Generator section.
REV. 1.0.2