XR16C2550 Datasheet, PDF (10/38 Pages) Exar Corporation – 2.97V TO 5.5V DUART WITH 16-BYTE FIFO

XR16C2550
2.97V TO 5.5V DUART WITH 16-BYTE FIFO
xr
REV. 1.0.1
FIGURE 5. EXTERNAL CLOCK CONNECTION FOR EXTENDED DATA RATE
External Clock
vcc
gnd
VCC
R1
2K
XTAL1
XTAL2
To obtain maximum data rate, it is necessary to use full rail swing on the clock input. See external clock
operating frequency over power supply voltage chart in Figure 6.
FIGURE 6. OPERATING FREQUENCY VERSUS POWER SUPPLY CHART.
Requires a 2K ohms pull-up resistor on XTAL2 pin to increase operating speed
Operating frequency for XR16C2550
with external clock and a 2K ohms
pull-up resistor on XTAL2 pin.
80
-40^oC
70
25^oC
85^oC
60
50
40
30
3.0 3.5 4.0 4.5 5.0 5.5
Suppy Voltage
10