Texas Instruments USBN9604SLBX

Overview

USBN9604SLBX from National Semiconductor is a full-speed USB 1.1 node controller IC integrating transceiver, 3.3V regulator, Serial Interface Engine (SIE), seven endpoint FIFOs (1×8-byte control + 6×64-byte data), 8-bit parallel/MICROWIRE interface, and enhanced DMA engine. It operates at 5V or 3.3V, supports 24 MHz crystal input with internal 48 MHz PLL clock generation, and targets embedded USB peripheral designs requiring low-EMI, bus-powered operation.

For engineers reviewing the USBN9604SLBX datasheet, USBN9604SLBX pinout, USBN9604SLBX application, or USBN9604SLBX equivalent, this page delivers verified technical context, exact pin functions for the 28-pin CSP package, real-world use cases in HID and industrial USB peripherals, and two validated alternative controllers with documented functional and interface differences.

Technical Context

The USBN9604SLBX implements a complete USB 1.1-compliant Serial Interface Engine (SIE) comprising Physical Layer (PHY) with NRZI decoding, clock recovery, bit stuffing/unstuffing, and Media Access Controller (MAC) handling CRC, packet formatting, and endpoint address detection. Its transceiver meets USB 1.1 Chapter 7 electrical requirements with differential receiver, single-ended receivers (0.8–2.0 V threshold), and slew-rate-controlled transmitter.

It features dual-mode microcontroller interfacing: non-multiplexed or multiplexed 8-bit parallel bus (MODE1-0 = 00/01) or synchronous MICROWIRE/PLUS (MODE1-0 = 10), with programmable interrupt polarity and open-drain/push-pull output. The enhanced DMA supports Automatic DMA (ADMA) mode for CPU-independent 64-byte packet transfers up to 16 KB per transaction, with automatic PID toggling and NAK recovery.

Key Specifications

Pinout & Package

USBN9604SLBX is housed in a 28-pin Chip Scale Package (CSP), footprint-identical to USBN9603SLB, optimized for space-constrained portable and embedded applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB node controller applications.

Compared with CY7C63xxx, USBN9604SLBX avoids MCU licensing and flash programming complexity but requires external firmware; versus USB1T11A, it eliminates full-stack development effort and delivers production-ready USB 1.1 compliance with zero custom logic.

Availability

USBN9604SLBX is available at Aetrix Electronics and suitable for industrial human interface devices, embedded USB peripherals, USB-to-parallel bridges, and legacy device adapters requiring stable component supply and long-term lifecycle support.

Supply support for USBN9604SLBX 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

National Semiconductor was a U.S.-based semiconductor company specializing in analog and interface ICs, acquired by Texas Instruments in 2011. Its legacy USB products remain widely deployed in industrial and embedded systems.

The USBN9604SLBX belongs to National's USB Node Controller product line, designed specifically to simplify USB peripheral integration for 8-bit and 16-bit microcontrollers without requiring USB protocol expertise or FPGA resources.

FAQ

What is the primary function of the USBN9604SLBX in a USB system?

The USBN9604SLBX serves as a full-speed USB 1.1 node controller, handling all USB protocol layers below the device class level - including physical transceiver operation, Serial Interface Engine (SIE) functions like packet formatting and CRC, endpoint management, and DMA-assisted data movement. It acts as a bridge between a host microcontroller and the USB bus, enabling the host to implement higher-level USB classes (e.g., HID, CDC) without managing low-level USB timing or handshaking. The USBN9604SLBX itself does not execute firmware; it is controlled entirely by an external processor via its parallel or MICROWIRE interface.

Does the USBN9604SLBX support USB 2.0 high-speed operation?

No, the USBN9604SLBX supports only USB Specification 1.1 full-speed operation at 12 Mbps. It lacks the high-speed transceiver circuitry, chirp signaling capability, and 480 Mbps PHY required for USB 2.0 compliance. All documentation, including the SNOS528L datasheet Revision 1.3, explicitly states USB 1.0/1.1 compatibility and makes no reference to high-speed mode. Applications requiring >12 Mbps bandwidth must use a different controller, such as a USB 2.0 transceiver paired with a separate high-speed SIE or a modern integrated solution.

How does the USBN9604SLBX handle power supply for USB bus-powered operation?

The USBN9604SLBX supports bus-powered operation through its integrated 3.3V voltage regulator (VREG), which derives 3.3V from the 5V USB VBUS line. This regulated output appears on the V3.3 pin and powers the internal transceiver and the mandatory 1.5 kΩ D+ pull-up resistor. When operating from a 3.3V system, the internal regulator is disabled, and the V3.3 pin becomes an input supplied externally. A 1 µF tantalum decoupling capacitor is required on V3.3 regardless of mode. The device also features a fully static HALT mode with asynchronous wake-up, allowing ultra-low standby current during USB suspend states.

What are the key differences between the USBN9604SLBX and the USBN9603SLBX?

The USBN9604SLBX and USBN9603SLBX are functionally identical except for their reset mechanisms: the USBN9604SLBX implements a hardware reset (RESET pin) that behaves identically to its power-on reset, including stalling CLKOUT for 214 XIN cycles while synchronizing its internal DLL. In contrast, the USBN9603SLBX uses a different clock generation reset scheme. All other specifications - pinout, endpoint FIFOs, DMA engine, interface modes, transceiver, and register set - are identical between the two parts, as confirmed in the shared SNOS528L datasheet.

Can the USBN9604SLBX operate with a 12 MHz crystal instead of 24 MHz?

No, the USBN9604SLBX requires a 24 MHz crystal or external 24 MHz clock source. Its internal PLL doubles this frequency to generate the precise 48 MHz clock needed for USB 1.1 full-speed timing (12 Mbps data rate requires 48 MHz SIE clock). A 12 MHz input would produce only 24 MHz - insufficient for compliant USB operation. The datasheet specifies "24 MHz fundamental crystal" and lists component values (e.g., 15 pF load capacitors) exclusively for 24 MHz; no alternate crystal frequencies are supported or characterized.