NXP Semiconductors SC16IS850LIBS,151

Overview

SC16IS850LIBS,151 from NXP Semiconductors is a single-channel UART IC with dual I²C-bus or SPI slave interface, supporting up to 5 Mbit/s data rate, 128-byte TX/RX FIFOs, 1.8 V operation, and integrated IrDA SIR encoder/decoder. It enables protocol conversion between I²C/SPI and RS-232/RS-485 in battery-powered industrial communication nodes.

For engineers reviewing the SC16IS850LIBS,151 datasheet, SC16IS850LIBS,151 pinout, SC16IS850LIBS,151 application, or SC16IS850LIBS,151 equivalent, key selection criteria include I²C/SPI interface select logic, HVQFN24 package thermal pad requirements, automatic RS-485 direction control via RTS, sleep current <5 µA at 1.8 V, and 128-byte programmable FIFO trigger levels.

Technical Context

The SC16IS850LIBS,151 implements a fully programmable UART core with backward-compatible 16C850 register mapping, supporting both 32-byte legacy and 128-byte extended FIFO modes controlled by TXINTLVL/RXINTLVL registers. Its baud rate generator accepts up to 80 MHz clock input and uses rational division (via CLKPRES + DLL/DLM) for precise custom rates.

Hardware flow control operates via RTS/CTS with EFR[6:7] enable, while software flow control uses programmable Xon/Xoff characters (single or double byte). RS-485 driver direction is managed automatically through RTS signal polarity inversion (AFCR1[2]) and turn-around timing (RS485TIME register), eliminating external transceiver control logic.

Key Specifications

Pinout & Package

HVQFN24 package (SOT616-3), 4 × 4 × 0.85 mm body with exposed thermal pad requiring solder connection to PCB ground plane for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SC16IS750IPW and MAX3107ETJ+, the SC16IS850LIBS,151 uniquely combines 128-byte FIFOs, dual I²C/SPI interface, integrated RS-485 direction control, and IrDA SIR-enabling compact, low-power, feature-rich serial bridging without external glue logic or voltage translation.

Availability

SC16IS850LIBS,151 is available at Aetrix Electronics and suitable for factory automation, portable diagnostics, and cellular data terminal applications requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant sourcing.

Supply support for SC16IS850LIBS,151 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 markets, with deep expertise in interface and mixed-signal IC design.

The SC16IS850LIBS,151 belongs to NXP's SC16IS family of intelligent UART bridges, engineered specifically for low-power, space-constrained industrial communication nodes needing seamless I²C/SPI-to-serial protocol conversion.

FAQ

What interface protocols does the SC16IS850LIBS,151 support?

The SC16IS850LIBS,151 supports I²C-bus (Fast-mode, 400 kbit/s) and SPI (Mode 0, up to 12 Mbit/s) as slave interfaces, selectable via the I2C/SPI pin. It does not operate as a master on either bus. The UART side supports RS-232 and RS-485 physical layers via external transceivers, with automatic RS-485 direction control enabled through RTS signaling. The SC16IS850LIBS,151 also integrates IrDA SIR encoding/decoding up to 115.2 kbit/s.

How does the SC16IS850LIBS,151 manage RS-485 driver direction without external logic?

The SC16IS850LIBS,151 uses its RTS output pin to directly control RS-485 driver direction, with configurable turn-around timing via the RS485TIME register. When automatic RS-485 mode is enabled (EFR[4]=1), the device asserts RTS before transmission and de-asserts it after the final stop bit, ensuring clean bus transitions. Polarity inversion (AFCR1[2]) allows mapping RTS functionality to DTR if required. This eliminates discrete direction-control circuitry in the SC16IS850LIBS,151 design.

What is the minimum supply voltage and sleep current specification for the SC16IS850LIBS,151?

The SC16IS850LIBS,151 operates down to 1.8 V and draws less than 5 µA in sleep mode at that voltage. Sleep mode activates automatically when RX is idle, TX FIFO and shift register are empty, and no pending interrupts remain except THR. This ultra-low quiescent current makes the SC16IS850LIBS,151 ideal for battery-powered field instruments and energy-harvesting sensor nodes requiring multi-year operational life.

Can the SC16IS850LIBS,151 be used with both crystal and external clock sources?

Yes, the SC16IS850LIBS,151 supports both configurations. A crystal (1–25 MHz) connects between XTAL1 and XTAL2 to form an internal oscillator. Alternatively, an external clock signal (up to 80 MHz) connects to XTAL1 only, with XTAL2 left unconnected. The baud rate generator uses this clock source - divided by a rational divisor (via CLKPRES, DLL, DLM) - to achieve precise UART rates, including non-standard values required in industrial protocols.

Does the SC16IS850LIBS,151 support hardware and software flow control simultaneously?

Yes, the SC16IS850LIBS,151 supports independent configuration of auto hardware flow control (RTS/CTS, enabled via EFR[6:7]) and auto software flow control (Xon/Xoff, enabled via EFR[5:4]). Both can be active concurrently: RTS manages local buffer overflow, CTS responds to remote buffer status, and Xon/Xoff characters handle flow control at the data-link layer. Trigger levels for each are separately programmable - FCR[7:4] for legacy mode or FLWCNTH/FLWCNTL for extended mode - ensuring robust operation in mixed-protocol environments.