Diodes Incorporated PI7C9X760CZDE

Overview

PI7C9X760CZDE from Diodes Incorporated is a single-channel I²C/SPI-to-UART bridge controller with 64-byte TX/RX FIFOs, programmable baud rates up to 16 Mbit/s (4× sampling), hardware/software flow control, and up to eight GPIOs. It supports RS-232/RS-485 interface bridging in industrial automation and embedded battery-powered systems.

For engineers reviewing the PI7C9X760CZDE datasheet, PI7C9X760CZDE pinout, PI7C9X760CZDE application, or PI7C9X760CZDE equivalent, key selection criteria include I²C/SPI host interface compatibility, 64-byte FIFO depth, auto RTS/CTS flow control timing behavior, and GPIO configurability for modem control signals (DSR/DTR/CD/RI).

Technical Context

The PI7C9X760CZDE implements a register-compatible extension of the 16C450 UART architecture with enhanced FIFO management, dual-mode flow control (hardware via RTS/CTS, software via Xon/Xoff), and automatic RS-485 driver direction control triggered by RTS polarity. Its internal baud rate generator supports fractional divisors for precise timing across wide clock inputs (up to 64 MHz).

It operates in either I²C-bus slave mode (fast-mode, 400 kHz) or SPI slave mode (Mode 0, up to 33 Mbps), with interface selection determined by the I2C/SPI pin level. The device integrates IrDA SIR encoding/decoding (115.2 kbps standard, optional 1.152 Mbps) and supports crystal (24 MHz max) or external clock (64 MHz max) timing sources.

Key Specifications

Pinout & Package

PI7C9X760CZDE is supplied in a 24-pin TQFN package (4×4 mm, 0.5 mm pitch) with exposed thermal pad connected to VSS. Pin functions are shared between I²C and SPI modes via configuration pins (I2C/SPI, CS/A0, SI/A1), and GPIOs support dual-role assignment (e.g., GPIO4/DSR).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SC16IS752IPW and MAX3107EEG+, the PI7C9X760CZDE uniquely combines dual-interface flexibility (I²C/SPI), RS-485 direction control, IrDA SIR, and eight GPIOs - making it optimal for mixed-protocol, space-aware industrial edge nodes.

Availability

PI7C9X760CZDE is available at Aetrix Electronics and suitable for industrial automation, embedded modem interfacing, and battery-powered handheld applications requiring stable component supply and long-term manufacturability.

Supply support for PI7C9X760CZDE 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, energy-efficient components for industrial, computing, and consumer markets.

The PI7C9X760 belongs to Diodes' UART bridge controller product line, designed specifically to simplify serial interface integration in resource-constrained embedded systems with I²C or SPI host buses.

FAQ

What interface protocols does the PI7C9X760CZDE support?

The PI7C9X760CZDE supports both I²C-bus (fast-mode, 400 kHz) and SPI (Mode 0, up to 33 Mbps) as host-side interfaces, selectable via the I2C/SPI pin. It does not support UART-to-UART bridging or USB. Each mode uses distinct pin assignments for clock, data, and chip select/address lines, and register access remains consistent across both interfaces.

How does the PI7C9X760CZDE handle RS-485 half-duplex direction control?

The PI7C9X760CZDE uses the RTS output signal to automatically control RS-485 driver direction: RTS goes low before transmission starts and returns high after the final stop bit. This behavior is enabled via the Enhanced Feature Register (EFR[6]) and requires no external logic. Direction control inversion is also supported through EFR[5], allowing compatibility with inverted-enable transceivers.

Can the GPIO pins be used simultaneously as modem control signals and general-purpose I/O?

No - GPIO4 through GPIO7 are multiplexed: each can operate either as a generic I/O or as a dedicated modem signal (DSR, DTR, CD, RI), but not both concurrently. Configuration is done via the GPIO Control Register (GPIOR[7:4]), and the selected function persists until reprogrammed. GPIO0–GPIO3 remain fully general-purpose with no modem role.

What is the maximum crystal frequency supported for the PI7C9X760CZDE?

The PI7C9X760CZDE supports a maximum crystal frequency of 24 MHz across XTAL1/XTAL2. When using an external clock instead of a crystal, the maximum input frequency rises to 64 MHz. The internal oscillator circuit is only active when a crystal is connected; external clocks bypass the oscillator and feed directly into the timing path.