NXP Semiconductors SC16IS741IPW,112

Overview

SC16IS741IPW,112 from NXP Semiconductors is a single-channel UART bridge IC with I²C-bus or SPI slave interface, supporting up to 5 Mbit/s data rates, 64-byte TX/RX FIFOs, and automatic RS-485 direction control via RTS. It operates at 2.5 V or 3.3 V, features software reset, IrDA SIR support, and targets battery-powered industrial serial gateways.

For engineers reviewing the SC16IS741IPW,112 datasheet, SC16IS741IPW,112 pinout, SC16IS741IPW,112 application, or SC16IS741IPW,112 equivalent, key selection criteria include dual-interface flexibility (I²C/SPI), low sleep current (<30 µA), hardware/software flow control, RS-485 auto-direction, and 16C450 register compatibility for legacy software porting.

Technical Context

The SC16IS741IPW,112 implements a full-duplex UART with programmable baud rate generator (divisor range 1–65535), selectable 16× or 4× clock mode, and independent RX/TX FIFO trigger level programming via TLR or FCR. Its register set is fully backward-compatible with the 16C450, enabling direct software reuse.

It supports two distinct physical interfaces: I²C-bus slave mode (400 kbit/s fast-mode compliant, noise-filtered SCL/SDA) and SPI slave mode (Mode 0 only), selected by the dedicated I2C/SPI pin. Both interfaces share identical register access and interrupt behavior via IRQ (open-drain, active LOW).

Key Specifications

Pinout & Package

TSSOP16 package (SOT403-1), 4.4 mm body width, surface-mount compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar UART bridge applications.

Compared with SC16IS741IPW,112, the SC16IS752IPW,118 offers dual-channel capability in the same footprint but increases complexity for single-link use, while the MAX3107ETJ+ provides deeper FIFOs and broader voltage support but sacrifices I²C interface flexibility and RS-485 hardware automation.

Availability

SC16IS741IPW,112 is available at Aetrix Electronics and suitable for factory automation, portable diagnostics, and cellular terminal designs requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant sourcing.

Supply support for SC16IS741IPW,112 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with broad expertise in interface, RF, and microcontroller technologies.

The SC16IS741IPW,112 belongs to NXP's SC16IS family of intelligent UART bridges, designed specifically to simplify serial protocol conversion in resource-constrained embedded systems while maintaining software compatibility with legacy platforms.

FAQ

What interface protocols does the SC16IS741IPW,112 support?

The SC16IS741IPW,112 supports I²C-bus slave mode (up to 400 kbit/s) and SPI slave mode (Mode 0 only). Interface selection is controlled by the dedicated I2C/SPI pin: logic HIGH selects I²C, logic LOW selects SPI. Both interfaces provide identical register-level access to the UART and share the same IRQ output behavior. The SC16IS741IPW,112 does not support master-mode operation on either bus.

Does the SC16IS741IPW,112 support automatic RS-485 half-duplex direction control?

Yes, the SC16IS741IPW,112 provides built-in automatic RS-485 driver direction control via its RTS output pin. When enabled through the Enhanced Feature Register (EFR[6]), RTS toggles automatically based on RX FIFO fill level - asserting LOW when space is available and deasserting HIGH when the FIFO nears capacity. This eliminates external direction-control logic and ensures glitch-free bus arbitration. The SC16IS741IPW,112 also supports RTS polarity inversion for compatibility with inverted-enable transceivers.

What is the maximum UART data rate achievable with the SC16IS741IPW,112?

The SC16IS741IPW,112 supports UART data rates up to 5 Mbit/s when operating in 16× clock mode with an appropriate crystal or external clock source. This maximum rate assumes proper configuration of the programmable baud rate generator (DLL/DLH registers) and prescaler (MCR[7]). At lower rates (e.g., 9600 or 115200 bps), the SC16IS741IPW,112 achieves zero percent error using common crystals like 1.8432 MHz or 3.072 MHz, as verified in Tables 7 and 8 of the official datasheet.

How does the SC16IS741IPW,112 handle low-power operation?

The SC16IS741IPW,112 enters Sleep mode when EFR[4] and IER[4] are both set, and conditions are met: RX line idle, TX FIFO and shift register empty, and no pending interrupts except THR. In Sleep mode, the internal UART clock stops, reducing current draw to less than 30 µA at 3.3 V. Wake-up occurs on RX activity, modem pin change, or TX FIFO write. Note that DLL/DLH writes must be performed before entering Sleep mode, as baud rate programming is disabled during sleep.

Is the SC16IS741IPW,112 software-compatible with legacy UARTs?

Yes, the SC16IS741IPW,112 features a register set fully backward-compatible with the industry-standard 16C450 UART. This allows existing drivers and firmware written for 16C450-based systems to operate without modification when interfacing with the SC16IS741IPW,112. All core registers - including RHR/THR, IER, FCR, LCR, MCR, LSR, and MSR - retain identical bit definitions and memory-mapped addresses, ensuring seamless software porting across platforms.