XR19L400 SINGLE CHANNEL INTEGRATED UART AND RS-485 TRANSCEIVER APRIL 2018 REV. 1.0.4 APPLICATIONS GENERAL DESCRIPTION Battery-Powered Equipment The XR19L400 (L400) is a highly integrated device that combines a full-featured single channel Universal Handheld and Mobile Devices Asynchronous Receiver and Transmitter (UART) and RS- Handheld Terminals 485 transceivers. The L400 is designed to operate with a Industrial Peripheral Interfaces single 3.3V or 5V power supply. The L400 is fully compliant with RS-485 Standards. Point-of-Sale (POS) Systems The L400 operates in four different modes: Active, Partial FEATURES Sleep, Full Sleep and Power-Save. Each mode can be invoked via hardware or software. Upon power-up, the Meets true RS-485 standards at 3.3V or 5V operation L400 is in the Active mode where the UART and RS-485 transceiver function normally. In the Partial Sleep mode, the Up to 8 Mbps data transmission rate internal crystal oscillator of the UART or charge pump of the 45us sleep mode exit (charge pump to full power) RS-485 transceiver is turned off. In Full Sleep mode, both ESD protection for RS-485 I/O pins at the crystal oscillator and the charge pump are turned off. +/-15kV - Human Body Model While the UART is in the Sleep mode, the Power-Save +/- 8kV - IEC 61000-4-2, Contact Discharge mode isolates the core logic from the control signals (chip select, read/write strobes, address and data bus lines) to +/- 15kV - IEC 61000-4-2, Air-Gap Discharge minimize the power consumption. The RS-485 receivers Software compatible with industry standard 16550 UART remain active in any of these four modes. Intel/Motorola bus select Complete modem interface Sleep and Power-save modes to conserve battery power Wake-up interrupt upon exiting low power modes FIGURE 1. BLOCK DIAGRAM *5 V Tolerant Inputs Crystal Charge Pump BRG Osc/Buffer PwrSave A2:A0 64 Byte TX+ TX D7:D0 TX FIFO TX- IOR RX+ 64 Byte IOW (R/W ) RX RX FIFO RX- CS (CS ) VCC33 INT (IRQ ) RESET (RESET ) CTS Modem I/M DSR I/Os HALF/FULL RI CD UART RS-485 Transceiver XR19L400 1 Intel or Motorola Bus Interface UART Registers XTAL1 XTAL2 GND VCC33 R EN VCC50 ACP C1+ C1-XR19L400 SINGLE CHANNEL INTEGRATED UART AND RS-485 TRANSCEIVER REV. 1.0.4 FIGURE 2. PIN OUT OF THE DEVICE D0 30 TXA- D0 30 TXA- 1 1 D1 NC D1 NC 2 29 2 29 D2 3 28 RXA+ D2 3 28 RXA+ D3 4 27 RXA- D3 4 27 RXA- XR19L400 XR19L400 D4 5 26 C1+ D4 5 26 C1+ 40-pin QFN 40- pin QFN D5 6 25 C1- D5 6 25 C1- Motorola Bus Mode Intel Bus Mode D6 NC D6 NC 7 24 7 24 D7 8 23 NC D7 8 23 NC 9 22 9 22 CS NC CS NC TEST2 10 21 VCC33 TEST2 10 21 VCC33 VCC GND (1) ORDERING INFORMATION PART NUMBER OPERATING TEMPERATURE RANGE LEAD-FREE PACKAGE PACKAGING METHOD (2) XR19L400IL40TR-F -40C to +85C Yes 40-pin QFN Tape and Reel NOTES: 1. Refer to www.exar.com/XR19L400 for most up-to-date Ordering Information. 2. Visit www.exar.com for additional information on Environmental Rating. 2 11 POWERSAVE 40 A0 12 XTAL1 39 A1 XTAL2 13 38 A2 IOW 14 37 INT 15 IOR 36 TEST1 NC 16 35 TEST0 I/M 17 34 HALF/FULL 18 RESET VCC50 33 19 ACP 32 TXA+ 20 R EN 31 GND 11 POWERSAVE 40 A0 12 XTAL1 39 A1 XTAL2 13 38 A2 R/W 14 37 IRQ 15 NC 36 TEST1 NC 16 35 TEST0 I/M 17 34 HALF/FULL 18 RESET VCC50 33 19 ACP 32 TXA+ 20 R EN 31 GND