NXP Semiconductors LPC11U34FBD48/421,

Overview

LPC11U34FBD48/421 from NXP Semiconductors is a 32-bit ARM Cortex-M0 microcontroller in LQFP48 package, operating at up to 50 MHz with 48 kB flash, 10 kB total SRAM (8 kB + 2 kB USB), and 4 kB EEPROM. It integrates USB 2.0 full-speed device controller, USART with RS-485/smart card support, I²C-bus (Fast-mode Plus), two SSP interfaces, 10-bit ADC (8 channels), and 40 GPIO pins - deployed in USB audio devices and handheld scanners.

For engineers reviewing the LPC11U34FBD48/421 datasheet, LPC11U34FBD48/421 pinout, LPC11U34FBD48/421 application, or LPC11U34FBD48/421 equivalent, key selection criteria include USB device stack readiness, on-chip EEPROM for configuration storage, fractional baud rate generation in USART, Fast-mode Plus I²C (1 Mbit/s), and deep power-down wake-up via dedicated WAKEUP pin.

Technical Context

The LPC11U34FBD48/421 implements an ARM Cortex-M0 core with NVIC and system tick timer, paired with a dedicated USB PLL enabling independent 48 MHz USB clock generation. Its memory subsystem includes 48 kB flash with sector/page erase, 4 kB byte-erasable EEPROM with ROM API, and dual SRAM banks (8 kB general-purpose + 2 kB USB-dedicated).

Peripheral integration centers on flexible serial connectivity: one USART supporting asynchronous smart card (ISO 7816-3), synchronous mode, and RS-485; two SSP controllers with FIFO and multi-protocol capability; and I²C-bus with Fast-mode Plus compliance (1 Mbit/s) and monitor mode. Power management includes four low-power modes (Sleep, Deep-sleep, Power-down, Deep power-down) with wake-up sources including USB activity and GPIO.

Key Specifications

Pinout & Package

LQFP48 package: plastic low-profile quad flat package, 48 leads, body 7 × 7 × 1.4 mm (SOT313-2), lead pitch 0.5 mm, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ARM Cortex-M0 USB microcontroller applications.

Compared with LPC11U35FBD48/401 and LPC11U36FBD48/401, the LPC11U34FBD48/421 offers optimal cost/performance balance for USB audio and scanner applications where 48 kB flash suffices - avoiding over-provisioned memory while retaining full USB, USART, and ADC capability.

Availability

LPC11U34FBD48/421 is available at Aetrix Electronics and suitable for USB audio devices, handheld scanners, and medical diagnostic tools requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for LPC11U34FBD48/421 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT markets.

The LPC11U3x product line targets cost-sensitive, USB-connected embedded systems - delivering ARM Cortex-M0 performance with integrated USB device stack, EEPROM, and industrial-grade serial interfaces in compact packages.

FAQ

What is the maximum CPU frequency supported by the LPC11U34FBD48/421?

The LPC11U34FBD48/421 supports a maximum CPU frequency of 50 MHz, achieved using either the internal 12 MHz IRC oscillator with PLL or an external crystal (1–25 MHz) with PLL multiplication. This frequency is validated across the full industrial temperature range (-40 °C to +85 °C) and 1.8–3.6 V supply.

Does the LPC11U34FBD48/421 include on-chip EEPROM, and what are its key characteristics?

Yes, the LPC11U34FBD48/421 integrates 4 kB of on-chip EEPROM that is byte-erasable and byte-programmable. It includes ROM-based API support for reliable wear leveling and endurance - rated for 100,000 write/erase cycles - eliminating the need for external serial EEPROM in applications like calibration storage or device configuration.

Can the LPC11U34FBD48/421 operate in low-power modes, and how is wake-up handled from Deep power-down?

Yes, the LPC11U34FBD48/421 supports four reduced-power modes, including Deep power-down. Wake-up from Deep power-down is enabled exclusively via the dedicated PIO0_16/WAKEUP pin, which features a 20 ns glitch filter. The pin must be externally pulled HIGH before entering Deep power-down and then driven LOW to initiate wake-up - ensuring ultra-low leakage current (<1 μA).

What USB capabilities does the LPC11U34FBD48/421 provide, and is external PHY required?

The LPC11U34FBD48/421 includes a full-speed USB 2.0 device controller with integrated transceiver - no external PHY is required. It supports SoftConnect via the USB_CONNECT pin, ROM-based USB device stack (CDC, HID, MSC classes), and flash updates over USB. The USB_DP/USB_DM pins connect directly to the USB connector with standard 27 Ω series resistors.

How many ADC channels does the LPC11U34FBD48/421 support, and what is its resolution?

The LPC11U34FBD48/421 features a 10-bit successive approximation ADC with multiplexing across eight input pins (AD0–AD7). It supports programmable conversion speed, burst mode, and hardware trigger sources (e.g., timer match), delivering accurate analog sensing for medical, industrial, and consumer applications without external ADC components.