XR19L200_07 Datasheet, PDF (4/40 Pages) Exar Corporation – SINGLE CHANNEL INTEGRATED UART AND RS-232 TRANSCEIVER

XR19L200
SINGLE CHANNEL INTEGRATED UART AND RS-232 TRANSCEIVER
Pin Descriptions
REV. 1.0.1
NAME
32-QFN
PIN#
TYPE
DESCRIPTION
I/M#
2
I _{Intel or Motorola Bus Select.}
When I/M# pin is HIGH, 16 or Intel Mode, the device will operate in the Intel bus type of
interface.
When I/M# pin is LOW, 68 or Motorola mode, the device will operate in the Motorola bus
type of interface.
RESET
23
(RESET#)
I _{When I/M# pin is HIGH for Intel bus interface, this input becomes RESET (active high).}
When I/M# 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 outputs of
the UART. The UART transmitter output will be held HIGH, the receiver input will be ignored
and outputs are reset during reset period (see Table 11).
C2+
15
- _{Charge pump capacitors. As shown in Figure 1, a 0.1 uF capacitor should be placed}
C2-
16
between these 2 pins.
C1+
24
- _{Charge pump capacitors. As shown in Figure 1, a 0.1 uF capacitor should be placed}
C1-
25
between these 2 pins.
VREF+
26
Pwr _{+5.0V generated by the charge pump.}
VREF-
17
Pwr _{-5.0V generated by the charge pump.}
VCC
27
Pwr _{3.0V to 5.5V power supply. All CMOS/TTL input pins, except XTAL1, are 5V tolerant.}
GND
13
Pwr _{Power supply common, ground.}
GND
-
Pwr _{The center pad on the backside of the 32-QFN package is metallic and is not electrically}
connected to anything inside the device. It must be soldered on to the PCB and may be
optionally 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 thermal pad.
NC
-
- _{No Connect. Note that in Motorola mode, the IOR# pin also becomes an NC pin.}
NOTE:
Pin type: I=Input, O=Output, I/O= Input/output, OD=Output Open Drain. For CMOS/TTL Voltage levels, ’LOW’
indicates a voltage in the range 0V to VIL and ’HIGH" indicates a voltage in the range VIH to VCC. For RS-232
input voltage levels, ’LOW’ is any voltage < -3V and ’HIGH’ is any voltage > 3V. For RS-232 output voltage levels,
’LOW’ is any voltage < -5V and ’HIGH’ is any voltage > 5V.
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