Overview
Information | High-Performance 2.25V - 5.5V DUART |
---|---|
Data Bus Interface | Intel, Motorola |
# of Channels | 2 |
Max Data Rate 5V (Mbps) | 6.25 |
Max Data Rate 3.3V (Mbps) | 4 |
Max Data Rate 2.5V (Mbps) | 3 |
Max Data Rate 1.8V (Mbps) | na |
Tx FIFO (Bytes) | 64 |
Rx FIFO (Bytes) | 64 |
Auto Flow Control | ✔ |
Auto RS-485 Half-Duplex Control | ✔ |
Multidrop (9-bit) Mode | |
Fractional Baud Rate Generator | |
Power Down Mode | ✔ |
Supply Voltage Range VCC (V) | 2.25 to 5.5 |
Auto RTS/CTS | ✔ |
Package | TQFP-48 |
FIFO Level Counters | ✔ |
Selectable/ Programable Trigger Levels | P |
IrDA Sup | ✔ |
5V Tolerant Inputs | ✔ |
Max UART/GPIO Input Voltage (V) | 5.5 |
Max UART/GPIO Output Voltage (V) | VCC |
Temperature Range (°C) | -40 to 85 |
The XR16L2751 UART (Universal Asynchronous Receiver Transmitter) is a dual-channel, 2.25V to 5.5V supply product with 5V tolerant inputs. It has a selectable Intel or Motorola data bus interface, and its pin-out is comparable to the ST16C2550CQ and XR16C2850CM. It has a PowerSave feature in sleep mode; this isolates the data bus interface from other bus activities that could cause a wasteful power drain. The PowerSave feature also eliminates the requirement for external buffers, which can reduce cost and board space.
Several device family features can enable more data byte transfer per interrupt service -- this can lower CPU bandwidth requirements. The programmable TX and RX FIFO interrupt trigger levels, and FIFO counters, further reduce the interrupt service period. Additionally, the automatic hardware (RTS/CTS) and software (Xon/Xoff) flow control (with auto RTS hysteresis) eliminates data loss and re-transmission, which can increase data throughput.
Data rates of up to 6.125Mbps at 5V, 4Mbps at 3.3V and 3Mbps at 2.5V are supported at 8x sampling clock rate. The device supports on-chip crystal oscillator or external clock inputs. The 2751 is offered in a low profile 48-pin TQFP package in commercial and industrial temperature grade.
- Support data rates up to 6.125Mbps at 5.0V, 4 Mbps at 3.3V, and 3 Mbps at 2.5V
- Transmit and receive FIFO level counters
- Automatic Sleep-mode
- Automatic Xon/Xoff software flow control
- Data rate up to 6.25 Mbps
- Infrared (IrDA 1.0) data encoder/decoder
- Programmable Tx and Rx FIFO trigger levels
- Automatic RTS/CTS
- Pb-Free, RoHS Compliant Versions Offered
- Portable Appliances
- Factory Automation and Process control
- Cellular Data Devices
- Ethernet Network Routers
- Telecommunications Network Routers
Documentation & Design Tools
Type | Title | Version | Date | File Size |
---|---|---|---|---|
Data Sheets | XR16L2751 2.25V to 5.5V DUART with 64-Byte FIFO and Powersave | 1.2.3 | April 2010 | 1.1 MB |
Application Notes | DAN-190, MaxLinear UARTs in RS-485 Applications | R01 | July 2023 | 2.4 MB |
Application Notes | AN-204, UART Sleep Mode | 1.0.0 | June 2010 | 515.8 KB |
Application Notes | DAN-176, Power-Save Feature: Sleep Current Down to 15µA | 1.0.0 | August 2004 | 42.5 KB |
Application Notes | DAN-161, Migrating from XR16C2850 to XR16L2751 | 1.0.0 | August 2002 | 23 KB |
Application Notes | DAN-130, ST16C2550 vs. TL16C752B | 1.0.0 | June 2002 | 119.3 KB |
User Guides & Manuals | Evaluation Board User's Manual | 1.3.0 | August 2003 | 24.7 KB |
Product Brochures | Interface Brochure | R01 | June 2024 | 3.6 MB |
Schematics & Design Files | ISA Eval Board Schematic | 1.4.0 | August 2007 | 109 KB |
Schematics & Design Files | PCI Eval Board Schematic | 1.1.0 | July 2007 | 167.8 KB |
Software: Drivers | Linux 2.6.13 | 1.0.0 | December 2009 | 10.8 KB |
Software: Drivers | Linux 2.6.18 | 1.0.0 | December 2009 | 12.1 KB |
Software: Drivers | Windows XP & 2000 | 1.3.0.0 | December 2009 | 61 KB |
Simulation Models
Package Type | Vcc | Temp | Mode | Version | File |
---|---|---|---|---|---|
TQFP | 2.5V | Commercial | Intel | 2 | |
TQFP | 2.5V | Commercial | Motorola | 1 | |
TQFP | 3.3V | Commercial | Intel | 2 | |
TQFP | 3.3V | Commercial | Motorola | 1 | |
TQFP | 5V | Commercial | Intel | 2 | |
TQFP | 5V | Commercial | Motorola | 1 | |
TQFP | 2.5V | Industrial | Intel | 2 | |
TQFP | 2.5V | Industrial | Motorola | 1 | |
TQFP | 3.3V | Industrial | Intel | 2 | |
TQFP | 3.3V | Industrial | Motorola | 1 | |
TQFP | 5V | Industrial | Intel | 2 | |
TQFP | 5V | Industrial | Motorola | 1 |
Quality & RoHS
Part Number | RoHS | Exempt | RoHS | Halogen Free | REACH | TSCA | MSL Rating / Peak Reflow | Package |
---|---|---|---|---|---|---|---|
XR16L2751CM-F | N | Y | Y | Y | Y | L3 / 260ᵒC | TQFP48 |
XR16L2751IM-F | N | Y | Y | Y | Y | L3 / 260ᵒC | TQFP48 |
Click on the links above to download the Certificate of Non-Use of Hazardous Substances.
Parts & Purchasing
Part Number | Pkg Code | Min Temp | Max Temp | Status | Suggested Replacement | Buy Now | Order Samples | PDN |
---|---|---|---|---|---|---|---|---|
XR16L2751CM-F | TQFP48 | 0 | 70 | NRND | Order | |||
XR16L2751CMTR-F | TQFP48 | 0 | 70 | OBS | XR16L2751CM-F | |||
XR16L2751IM-F | TQFP48 | -40 | 85 | NRND | Order | |||
XR16L2751IMTR-F | TQFP48 | -40 | 85 | OBS | XR16L2751IM-F |
Active - the part is released for sale, standard product.
EOL (End of Life) - the part is no longer being manufactured, there may or may not be inventory still in stock.
CF (Contact Factory) - the part is still active but customers should check with the factory for availability. Longer lead-times may apply.
PRE (Pre-introduction) - the part has not been introduced or the part number is an early version available for sample only.
OBS (Obsolete) - the part is no longer being manufactured and may not be ordered.
NRND (Not Recommended for New Designs) - the part is not recommended for new designs.
Packaging
Pkg Code | Details | Quantities | Dimensions |
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TQFP48 |
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Notifications
FAQs & Support
Search our list of FAQs for answers to common technical questions.
For material content, environmental, quality and reliability questions review the Quality tab or visit our Quality page.
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Please check that all the following conditions are satisfied first.
- no interrupts pending (ISR bit-0 = 1)
- modem inputs are not toggling (MSR bits 0-3 = 0)
- RX input pin is idling HIGH • divisor (the value in DLL register) is non-zero
- TX and RX FIFOs are empty
Be sure sleep mode bit has been set to 1. If there are multiple UART channels, the sleep conditions must be true for all channels.
See more on Sleep Mode in AN204 UART Sleep Mode.
Yes. Note: some devices do have powersave mode. If UART goes into powersave mode, then the registers are not accessible.
See more on Sleep Mode in AN204 UART Sleep Mode.
Read LSR register to check whether the UART receives the data or not.
- If LSR value is 0x60, it means that either UART receiver FIFO doesn’t receive the data or the data in receiver FIFO has been read out before the read of LSR.
- If LSR value is 0x00, it means data is still in the THR (clock doesn’t oscillate to transmit data).
- If LSR value is 0xFF, it means either UART is in powersave mode or UART is powered off. For those devices with powersave mode, be sure that UARTS are not in powersave mode.
See more on Sleep Mode in AN204 UART Sleep Mode.
- Check whether the register set can be accessed.
- Check whether the crystal is oscillating fully.
- Check whether the data can be transmitted in internal loopback mode.
See more on Sleep Mode in AN204 UART Sleep Mode.
Videos
MxL UARTs Auto RS-485 Direction Control
This video describes how the automatic RS-485 half-duplex direction control feature in MaxLinear UARTs reduces driver development and frees up CPU/MCU loading. This feature eliminates the need to monitor the status of the UART’s transmit shift register and automatically switches MaxLinear RS-485 transceivers from the transmit mode to the receive mode. This video summarizes the content in application note DAN-190.