NXP Semiconductors SC18IS600IBS,128

Overview

SC18IS600IBS,128 from NXP Semiconductors is an SPI-to-I²C bridge IC that enables a microcontroller's SPI interface to control I²C-bus slave devices. It operates as a single-master I²C controller with 400 kbit/s I²C speed, 1.2 Mbit/s SPI (Mode 3), and integrated 96-byte TX/RX buffers. Used in embedded systems requiring protocol translation between host processors and sensor or EEPROM peripherals.

For engineers reviewing the SC18IS600IBS,128 datasheet, SC18IS600IBS,128 pinout, SC18IS600IBS,128 application, or SC18IS600IBS,128 equivalent, key selection criteria include its TSSOP16 package, 2.4–3.6 V supply, 5 V-tolerant I/Os, power-down mode with WAKEUP pin, and support for quasi-bidirectional GPIO configuration via IOConfig register.

Technical Context

The SC18IS600IBS,128 implements a dedicated hardware I²C-bus controller with full protocol handling-including arbitration, START/STOP generation, ACK/NACK management, and clock stretching-offloading timing-critical tasks from the host MCU. Its internal RC oscillator runs at 7.3728 MHz ±1%, enabling precise I²C clock derivation via the programmable I2CClk register.

It uses a register-mapped SPI slave interface where commands (e.g., 0x00 for write, 0x01 for read, 0x20/0x21 for register access) initiate discrete I²C transactions. Status reporting occurs through the I2CStat register (e.g., 0xF0 = success, 0xF1 = address NACK), and interrupts are signaled on the open-drain INT pin upon completion or error.

Key Specifications

Pinout & Package

TSSOP16 package (4.4 mm body width, SOT403-1); 16-pin surface-mount with exposed pad not present. Pin functions validated per NXP datasheet Rev. 8 (2019).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SPI-to-I²C bridge applications.

Compared with PCA9665D,112 and MAX7357ATL+, the SC18IS600IBS,128 uniquely delivers full hardware I²C master control over SPI with minimal host firmware involvement, making it the only solution among the three that offloads complete I²C protocol execution.

Availability

SC18IS600IBS,128 is available at Aetrix Electronics and suitable for industrial sensor hubs, smart energy metering, automotive body control modules, and IoT edge gateways requiring stable component supply across extended product lifecycles.

Supply support for SC18IS600IBS,128 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 company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The SC18IS600IBS,128 belongs to NXP's interface bridge IC product line, designed specifically to simplify communication between resource-constrained microcontrollers and legacy or mixed-voltage I²C peripherals in space- and power-sensitive embedded systems.

FAQ

What is the maximum I²C-bus clock frequency supported by the SC18IS600IBS,128?

The SC18IS600IBS,128 supports I²C-bus speeds up to 400 kbit/s (Fast-mode). The actual clock frequency is determined by the I2CClk register value and internal 7.3728 MHz oscillator; for example, I2CClk = 0x19 yields ~100 kHz, while minimum value 0x05 achieves ~369 kHz. The SC18IS600IBS,128 does not support High-speed mode (3.4 Mbit/s).

How does the SC18IS600IBS,128 handle I²C bus arbitration and clock stretching?

The SC18IS600IBS,128 fully implements I²C arbitration logic and automatically detects and responds to clock stretching by slave devices on the SCL line. It halts transmission until SCL is released, then resumes - all handled in hardware without host intervention. This behavior is confirmed in Section 6.3 of the SC18IS600IBS,128 datasheet.

Can the SC18IS600IBS,128 operate with a 5 V I²C bus while powered from 3.3 V?

Yes - all I/O pins of the SC18IS600IBS,128, including SDA and SCL, are 5 V tolerant. When interfacing with a 5 V I²C bus, external 5 V pull-ups are used on SDA/SCL, and the SC18IS600IBS,128 operates safely from its 2.4–3.6 V VDD supply. However, quasi-bidirectional pins should avoid sustained 5 V drive to minimize leakage current.

What is the function of the WAKEUP/IO4 pin on the SC18IS600IBS,128?

The WAKEUP/IO4 pin (Pin 15) serves dual roles: it wakes the SC18IS600IBS,128 from power-down mode when pulled LOW by the host, and functions as a quasi-bidirectional I/O in active mode. Unlike GPIO0–GPIO3, its mode is fixed and not software-configurable; it retains glitch suppression and Schmitt-triggered input characteristics.

Does the SC18IS600IBS,128 support SPI Mode 0 or only Mode 3?

The SC18IS600IBS,128 supports SPI Mode 3 exclusively (CPOL = 1, CPHA = 0), meaning SCLK is idle HIGH and data is sampled on the falling edge. Attempting Mode 0 (CPOL = 0, CPHA = 0) will result in communication failure. This is explicitly stated in Section 2 ("Features and benefits") and Section 6.4 of the SC18IS600IBS,128 datasheet.