Diodes Incorporated PI7C9X760ACLE

Overview

PI7C9X760 from Diodes Incorporated is a single-channel I²C-bus/SPI-to-UART bridge controller with 64-byte TX/RX FIFOs, backward-compatible register set (16C450), hardware/software flow control, and RS-485/RS-232 protocol bridging capability. It operates at 1.8V/2.5V/3.3V, supports up to 33 Mbps SPI clock, and integrates eight programmable GPIOs for embedded serial interface expansion in space-constrained systems.

For engineers reviewing the PI7C9X760 datasheet, PI7C9X760 pinout, PI7C9X760 application, or PI7C9X760 equivalent, key selection considerations include UART register compatibility, dual-interface (I²C/SPI) flexibility, auto RTS/CTS timing behavior, IrDA SIR support up to 1.152 Mbps, and GPIO mapping for modem control signals (DSR/DTR/CD/RI).

Technical Context

The PI7C9X760 implements a fully bidirectional protocol converter between I²C/SPI host buses and asynchronous serial (UART) peripherals, supporting both slave-only I²C (fast-mode, up to 400 kHz) and SPI Mode 0 (slave, ≤33 MHz). Its internal 16C450-compatible register map enables drop-in firmware reuse across legacy UART drivers.

It features dual flow control architectures: Auto-RTS/CTS hardware control with programmable RX FIFO halt/resume trigger levels (via TCR), and software Xon/Xoff control with dual-character support (Xon1/Xon2, Xoff1/Xoff2) and special-character detection. The device also embeds RS-485 driver direction control via RTS inversion and built-in IrDA encoder/decoder for SIR compliance.

Key Specifications

Pinout & Package

PI7C9X760 is housed in a 24-pin TQFN (ZD) package with 0.5 mm pitch and an exposed center thermal pad connected to VSS. Pin 1 index is marked by a dot; the center pad must be soldered to PCB ground 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 SC16IS752IPW and MAX3107EEG+, the PI7C9X760 uniquely balances I²C/SPI dual-interface support, IrDA SIR integration, and modem GPIO mapping-making it optimal for compact, multi-protocol edge nodes where interface flexibility and RF-adjacent serial control are co-required.

Availability

PI7C9X760 is available at Aetrix Electronics and suitable for industrial automation, smart metering, POS terminal design, and IoT gateway development requiring stable component supply, long-lifecycle assurance, and RoHS-compliant green packaging.

Supply support for PI7C9X760 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 communications markets.

The PI7C9X760 belongs to Diodes' high-integration UART bridge product line, designed specifically for resource-constrained embedded systems needing seamless I²C/SPI-to-serial conversion with minimal external components and extended feature coverage.

FAQ

What interface modes does the PI7C9X760 support, and how is mode selection implemented?

The PI7C9X760 supports I²C-bus (slave-only, fast-mode) and SPI (slave-only, Mode 0) interfaces. Mode selection is controlled by the I2C/SPI pin (Pin 5): logic HIGH selects I²C mode (activating SDA/SCL), and logic LOW selects SPI mode (activating SI/SO/SCLK/CS). This hardware-strapped configuration eliminates runtime reconfiguration overhead and ensures deterministic boot-time interface assignment.

How does the PI7C9X760 implement RS-485 driver direction control without external circuitry?

The PI7C9X760 uses its RTS output (Pin 21) to directly control RS-485 transceiver direction. When enabled via the Enhanced Feature Register (EFR[4]), RTS toggles automatically based on transmit activity. An optional polarity inversion bit (EFR[3]) allows compatibility with both active-high and active-low direction-enable inputs, eliminating external inverters or GPIO-based timing-critical control logic.

Can the GPIO pins on the PI7C9X760 be used simultaneously as modem control signals and general-purpose I/O?

No-GPIO4 through GPIO7 (Pins 17–20) are function-multiplexed: each can operate either as a general-purpose I/O or as a dedicated modem control signal (DSR/DTR/CD/RI), but not both concurrently. Configuration is performed via the GPIO Control Register (GPIOCR), and the selected mode persists until reprogrammed; no dynamic runtime switching between roles is supported.

What is the role of the Trigger Level Register (TLR) versus the FIFO Control Register (FCR) in managing UART interrupts?

The FCR provides fixed, coarse FIFO trigger level selections (1/4/8/14 bytes), while the TLR enables fine-grained, programmable thresholds (1–63 bytes) for both TX and RX FIFO interrupt generation. If TLR bits are non-zero, they override FCR settings; if cleared, FCR values take effect. This dual-layer control allows optimized interrupt frequency tuning for latency-sensitive or power-constrained applications.