Texas Instruments CP3UB17K38

Overview

CP3UB17K38 from National Semiconductor is a reprogrammable connectivity processor integrating a 24 MHz CR16C RISC core, 256 KB Flash program memory, 8 KB Flash data memory, 10 KB SRAM, and on-chip USB 1.1 controller with seven endpoint FIFOs. It serves as a system-level host controller in embedded USB peripheral devices requiring audio interface, low-power operation, and multi-protocol serial connectivity.

For engineers reviewing the CP3UB17K38 datasheet, CP3UB17K38 pinout, CP3UB17K38 application, or CP3UB17K38 equivalent, this device supports real-time audio processing via CVSD/PCM conversion, dual power modes (Active/Halt), and hardware-accelerated DMA transfers across USB, UART, AAI, and CVSD/PCM peripherals - critical for USB audio adapters, ISDN terminal equipment, and voice-enabled human interface devices.

Technical Context

The CP3UB17K38 implements a pipelined CR16C CPU core delivering one instruction per clock cycle at up to 24 MHz, with zero wait states for on-chip Flash execution. Its triple-clock architecture generates main (24 MHz), slow (32.768 kHz), and PLL-derived clocks - the latter feeding the USB transceiver and CVSD/PCM module.

Hardware peripherals include a four-channel DMA controller supporting concurrent transfers from USB, UART, Advanced Audio Interface (AAI), and CVSD/PCM; a 16-channel Multi-Input Wake-Up unit enabling edge-triggered wake from Halt/Idle modes; and a Versatile Timer Unit (VTU) with four independent subsystems configurable as 8-bit PWM, 16-bit PWM, or 16-bit counter with dual input capture.

Key Specifications

Pinout & Package

CSP-48 (Chip Scale Package), 0.5 mm pitch, 6 × 6 mm body size. Pinout validated per datasheet Figure 4-1 (Page 7) and Table 27-1 (Page 197).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar connectivity processor applications.

Compared with CY7C68013A-56PVXC and STM32F103CBT6, CP3UB17K38 delivers unique integration of USB 1.1 node, CVSD/PCM hardware, and MIWU - enabling single-chip voice-enabled USB peripherals with guaranteed wake latency and zero external audio components.

Availability

CP3UB17K38 is available at Aetrix Electronics and suitable for USB audio adapters, ISDN terminal equipment, smart human interface devices, and industrial USB peripheral controllers requiring stable component supply and long-term lifecycle support.

Supply support for CP3UB17K38 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 mixed-signal ICs, acquired by Texas Instruments in 2011. Its legacy connectivity processors emphasized integration of USB, audio, and low-power control in single-chip solutions.

The CP3UB17 product line was designed for embedded USB peripheral systems requiring real-time audio processing, multi-protocol serial connectivity (ACCESS.bus, SPI, UART), and deterministic low-power operation - targeting voice terminals, telecom adapters, and human interface devices.

FAQ

What is the maximum operating frequency of the CP3UB17K38 CPU core?

The CP3UB17K38 features a CR16C RISC core rated for operation up to 24 MHz, achieving a minimum instruction cycle time of 41.7 ns. This frequency is derived from a 12 MHz external crystal input through an on-chip PLL, and the core operates with zero wait states when accessing on-chip Flash memory - ensuring deterministic real-time performance for USB and audio tasks in the CP3UB17K38.

Does CP3UB17K38 support USB 2.0 High-Speed mode?

No, CP3UB17K38 implements a full-speed USB 1.1 node compliant with USB Specification 1.0 and 1.1, supporting data rates up to 12 Mbps. It does not support USB 2.0 High-Speed (480 Mbps) or USB 3.x protocols. The CP3UB17K38 USB controller includes an integrated transceiver, Serial Interface Engine (SIE), and seven endpoint FIFOs - all optimized for reliable full-speed operation in embedded peripheral applications.

Can CP3UB17K38 perform CVSD encoding without CPU intervention?

Yes, CP3UB17K38 contains a dedicated hardware CVSD/PCM conversion module that operates independently of the CPU. It supports bidirectional real-time voice encoding/decoding with DMA-assisted data movement to/from USB or AAI interfaces. This allows the CP3UB17K38 to maintain continuous CVSD streams at 64 kbps while freeing the CR16C core for protocol handling and system management tasks.

What power modes does CP3UB17K38 support, and how does wake-up work?

CP3UB17K38 supports four power modes: Active, Power Save, Idle, and Halt. Wake-up from Halt/Idle is handled by the 16-channel Multi-Input Wake-Up (MIWU) module, which detects rising/falling edges on dedicated input pins (including USB_RESUME, UART_RX, ACCESS.bus lines) and resumes operation in under 1 µs. This capability is integral to the CP3UB17K38's design for battery-powered USB peripherals requiring ultra-low standby current.

Is external memory supported on the CP3UB17K38 in CSP-48 package?

No, external memory interface is not available on the CP3UB17K38 CSP-48 variant. The Bus Interface Unit (BIU) and external address/data bus signals are only implemented on the 100-pin LQFP packages (e.g., CP3UB17G38). The CP3UB17K38 CSP-48 relies solely on its on-chip memory resources: 256 KB Flash program, 8 KB Flash data, and 10 KB SRAM - sufficient for self-contained USB peripheral firmware with integrated audio processing.