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XR19L200 4 SINGLE CHANNEL INTEGRATED UART AND RS-232 TRANSCEIVER REV. 1.0.1 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. 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 (RESET#) 23 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 C2+ C2- 15 16 - Charge pump capacitors. As shown in Figure 1, a 0.1 uF capacitor should be placed between these 2 pins. C1+ C1- 24 25 - Charge pump capacitors. As shown in Figure 1, a 0.1 uF capacitor should be placed 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. Pin Descriptions NAME 32-QFN PIN# TYPE DESCRIPTION |
