Click here to ask about the production status of specific part numbers. MAX3109 Dual Serial UART with 128-Word FIFOs General Description Benefits and Features 2 The MAX3109 advanced dual universal asynchronous Bridges an SPI/MICROWIRE or I C Microprocessor receiver-transmitter (UART) has 128 words of receive and Bus to an Asynchronous Interface Such as RS-485, SM transmit first-in/first-out (FIFO) and a high-speed SPI or RS-232, or IrDA 2 I C controller interface. The 2x and 4x rate modes allow SIR- and MIR-Compliant IrDA Encoder/Decoder Line Noise Indication Ensures Data Link Integrity a maximum of 24Mbps data rates. A phase-locked loop (PLL) and the fractional baud-rate generators allow a high Deep, 128-Word Buffer and Automated Control degree of flexibility in baud-rate programming and refer- Features Help Offload Activity on the Microcontroller ence clock selection. Automatic RTS and CTS Flow Control Independent logic-level translation on the transceiver and Automatic XON/XOFF Software Flow Control 9-Bit Multidrop-Mode Data Filtering controller interfaces allows ease of interfacing to micro- controllers, FPGAs, and transceivers that are powered - Special Character Detection - GPIO-Based Character Detection by differing supply voltages. Automatic hardware and - Two Timers Routed to GPIOs software flow control with selectable FIFO interrupt trig- - 8 Flexible GPIOs with 20mA Drive Capability gering offloads low-level activity from the host controller. Automatic half-duplex transceiver control with program- Saves Board Space mable setup and hold times allow the MAX3109 to be TQFN (5mm x 5mm) Package used in high-speed applications such as PROFIBUSDP. Dual UART in a Single Package The 128-word FIFOs have advanced FIFO control, reduc- Fast Data Rates Allow Maximum System Flexibility ing host processor data flow management. Across Interface Standards The MAX3109 is available in a 32-pin TQFN (5mm x 24Mbps (max) Data Rate 5mm) package and is specified over the -40C to +85C High-Resolution Programmable Baud-Rate extended temperature range. SPI Up to 26MHz Clock Rate 2 Fast Mode Plus I C Up to 1MHz Applications Integrated PLL and Divider Handheld Devices Medical Systems Power Management Control Features Minimize Power Meters Point-of-Sales Systems Power Consumption for Portable Applications Programmable Logic HVAC or Building Control 1.71V to 3.6V Supply Range Controllers (PLCs) Shutdown and Autosleep Modes - 1A Shutdown Current Functional Diagram Logic-Level Translation on the Controller and VL VCC V18 VEXT Transceiver Interfaces Ensure System Compatibility TRANSMITTER TX0 LDOEN LDO SYNC RX0 Register Compatible with MAX3107, MAX3108, and LOGIC-LEVEL 2 CTS0 TRANSLATION SPI/I2C RTS0 MAX148301 UART0 SPI MOSI/A1 GPIO0 AND MISO/SDA 2 GPIO1 I C CS/A0 GPIO2 INTERFACE REGISTERS SCLK/SCL GPIO3 AND LOGIC-LEVEL CONTROL MAX3109 TRANSLATION RST TX1 RX1 IRQ CTS1 RTS1 UART1 GPIO4 FRACTIONAL 2 GPIO5 XIN DIVIDER PLL BAUD-RATE CRYSTAL GPIO6 GENERATOR OSCILLATOR XOUT GPIO7 AGND DGND IrDA is a service mark of Infrared Data Association Corporation. 19-5806 Rev 6 8/20MAX3109 Dual Serial UART with 128-Word FIFOs TABLE OF CONTENTS Absolute Maximum Ratings ...................................................................... 7 Package Thermal Characteristics ................................................................. 7 DC Electrical Characteristics ..................................................................... 7 AC Electrical Characteristics 10 Timing Diagrams ............................................................................. 12 Typical Operating Characteristics ................................................................ 13 Pin Configuration ............................................................................. 14 Pin Description ............................................................................... 14 Detailed Description........................................................................... 16 Receive and Transmit FIFOs 16 Transmitter Operation 17 Receiver Operation 17 Line Noise Indication . 18 Clock Selection . 19 Crystal Oscillator . 19 External Clock Source . 19 PLL and Predivider 19 Fractional Baud-Rate Generators . 19 2x and 4x Rate Modes . 20 Low-Frequency Timer 20 UART Clock to GPIO 21 Multidrop Mode . 21 Auto Data Filtering in Multidrop Mode . 21 Auto Transceiver Direction Control 21 Transmitter Triggering and Synchronization . 21 Transmitter Synchronization 22 Intrachip and Interchip Synchronization . 22 Delayed Triggering 22 Trigger Accuracy . 22 Synchronization Accuracy 23 Auto Transmitter Disable . 24 Echo Suppression . 24 Auto Hardware Flow Control . 24 AutoRTS Control 24 AutoCTS Control . 25 Auto Software (XON/XOFF) Flow Control 25 Receiver Flow Control . 25 Transmitter Flow Control . 26 Maxim Integrated 2 www.maximintegrated.com