Diodes Incorporated PI7C9X1170BCLEX

Overview

PI7C9X1170BCLEX from Diodes Incorporated is an I²C-bus/SPI-to-UART bridge controller implementing a single-channel full-duplex UART with 64-byte TX/RX FIFOs, backward-compatible register mapping to the 16C450, and support for baud rates up to 16 Mbit/s (4× sampling) or 33 Mbps SPI interface. It operates across 1.8 V, 2.5 V, and 3.3 V supply rails and integrates eight programmable GPIO pins. Used in industrial computing and battery-operated embedded systems requiring protocol translation between microcontrollers and legacy serial peripherals.

For engineers reviewing the PI7C9X1170BCLEX datasheet, PI7C9X1170BCLEX pinout, PI7C9X1170BCLEX application, or PI7C9X1170BCLEX equivalent, key selection criteria include its dual-interface flexibility (I²C or SPI host side), hardware/software flow control implementation, RS-485 direction control via RTS, IrDA SIR support up to 1.152 Mbps, and compatibility with standard UART driver stacks targeting 16C450 register sets.

Technical Context

The PI7C9X1170BCLEX implements a register-compatible UART core with fully programmable character formatting (5–8 bit, parity, stop bits), fractional baud rate generation, and independent RX/TX FIFO trigger level control via FCR and TLR registers. Its interrupt architecture supports seven prioritized sources including Xoff detection, modem status change, and I/O pin transitions.

It supports both I²C-bus (fast-mode, slave-only, address strapping via A0/A1) and SPI (mode 0, slave-only, 33 Mbps max) host interfaces, with interface selection controlled by the I2C/SPI# pin. Internal logic enables automatic RS-485 half-duplex direction control using RTS polarity inversion and built-in IrDA encoder/decoder for SIR-compliant infrared communication.

Key Specifications

Pinout & Package

PI7C9X1170BCLEX is housed in a 24-pin TQFN package (ZD suffix) with exposed thermal pad. Pin assignment is fixed and validated per Diodes DS40307 Rev 8-2; all pins are electrically defined and functionally verified for I²C/SPI host interface, UART I/O, GPIO, and power domains.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SC16IS752IPW and MAX3107EAE+T, the PI7C9X1170BCLEX uniquely combines dual-interface flexibility (I²C/SPI), integrated RS-485 direction control, eight GPIOs, and IrDA SIR-making it optimal for cost-sensitive, space-constrained embedded systems requiring mixed-protocol interoperability.

Availability

PI7C9X1170BCLEX is available at Aetrix Electronics and suitable for industrial computing, factory automation, and battery-operated IoT edge nodes requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for PI7C9X1170BCLEX 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and integrated circuits, specializing in high-performance analog, logic, and interface solutions for industrial, computing, and consumer markets.

The PI7C9X1170 belongs to Diodes' UART bridge product line, engineered to simplify protocol translation between modern microcontrollers and legacy serial peripherals while minimizing external components and board space.

FAQ

What interface modes does the PI7C9X1170BCLEX support, and how is selection performed?

The PI7C9X1170BCLEX supports both I²C-bus (fast-mode, slave-only) and SPI (mode 0, slave-only) host interfaces. Interface selection is determined by the logic level on the I2C/SPI# pin at power-up: HIGH selects I²C mode, LOW selects SPI mode. This pin must be stable before VDD reaches 1.0 V to ensure correct initialization and register mapping.

How does the PI7C9X1170BCLEX implement RS-485 half-duplex direction control?

RS-485 direction control is implemented using the RTS# output pin, which can be configured to assert/deassert based on RX FIFO fill level. The halt and resume trigger thresholds are programmed in the Transmission Control Register (TCR). When enabled, RTS# goes LOW to enable the RS-485 driver when space remains in the RX FIFO, and goes HIGH to disable it when the FIFO nears full-eliminating external direction-control logic.

Can the PI7C9X1170BCLEX operate from a 1.8 V supply, and what are the implications for I/O voltage levels?

Yes, the PI7C9X1170BCLEX operates from 1.62 V to 3.6 V, including 1.8 V nominal supply. All digital I/O pins (GPIO, SDA, SCL, etc.) are fully specified at 1.8 V, with input thresholds scaled accordingly (e.g., 1.0 V for VIH min). No level-shifting circuitry is required when interfacing with 1.8 V microcontrollers, simplifying low-voltage system design.

Is the PI7C9X1170BCLEX pin-compatible with other UART bridges such as the SC16IS752?

No, the PI7C9X1170BCLEX is not pin-compatible with the SC16IS752 or other UART bridges. It uses a unique 24-pin TQFN (ZD) footprint with dedicated I2C/SPI# selection, dual VDD pins, and integrated IrDA functionality. Pin assignments-including GPIO multiplexing, IRQ#, and RTS#/CTS#-differ significantly, requiring custom PCB layout and driver adaptation.