NXP Semiconductors LPC11U68JBD48K

Overview

LPC11U68JBD48K from NXP Semiconductors is a 32-bit ARM Cortex-M0+ microcontroller in LQFP48 package, operating up to 50 MHz with 256 KB flash, 36 KB SRAM, and 4 KB EEPROM. It integrates USB 2.0 full-speed device controller (with XTAL-less low-speed mode), dual I²C interfaces (one Fast-mode Plus), five USARTs, two SSP controllers, 12-bit ADC (8 channels), RTC, temperature sensor, and PWM/timer subsystem with SCTimer/PWM capability. It targets embedded control applications requiring USB connectivity and mixed-signal integration.

For engineers reviewing the LPC11U68JBD48K datasheet, LPC11U68JBD48K pinout, LPC11U68JBD48K application, or LPC11U68JBD48K equivalent, key selection criteria include its 256 KB flash capacity, USB device + dual I²C + 5x USART peripheral set, LQFP48 footprint compatibility, and support for deep power-down wake-up via PIO0_16 - all confirmed for this exact variant per NXP Rev. 1.5 datasheet.

Technical Context

The LPC11U68JBD48K implements an ARM Cortex-M0+ core (r0p1) with two-stage pipeline, single-cycle I/O, and NVIC for deterministic interrupt handling. Its AHB multilayer matrix enables concurrent bus access between CPU, DMA, and peripherals including USB, ADC, and timers.

Peripheral architecture includes a dedicated USB PLL, system PLL for CPU clocking, and separate 32 kHz RTC oscillator with VBAT supply. The configurable SCTimer/PWM subsystem supports up to 19 PWM outputs with 6 independent time bases, while the 12-bit ADC achieves 2 Msamples/s with dual conversion sequences and internal/external trigger support.

Key Specifications

Pinout & Package

LQFP48 package (7 × 7 × 1.4 mm, SOT313-2) with 48 leads; lead pitch 0.5 mm; RoHS-compliant; thermal pad optional per NXP design guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LPC11U67JBD48 and LPC11U37FBD48, the LPC11U68JBD48K offers the highest on-chip memory (256 KB flash/36 KB SRAM) and retains full USB functionality with XTAL-less mode - making it optimal for feature-rich, field-upgradable USB devices where firmware scalability and peripheral integration are critical.

Availability

LPC11U68JBD48K is available at Aetrix Electronics and suitable for three-phase e-meter, car radio, and GPS tracker applications requiring stable component supply, long-term manufacturability, and industrial temperature range support.

Supply support for LPC11U68JBD48K 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 LPC11U6x product line is designed for cost-sensitive, USB-enabled embedded control applications demanding low power, rich analog/digital peripheral integration, and ARM Cortex-M0+ efficiency - targeting smart sensors, portable medical devices, and industrial HMI systems.

FAQ

What is the maximum operating frequency of the LPC11U68JBD48K?

The LPC11U68JBD48K operates at a maximum CPU frequency of 50 MHz, achieved via its ARM Cortex-M0+ core and system PLL. This frequency is supported across the full industrial temperature range (−40 °C to 105 °C) and 2.4 V to 3.6 V supply voltage, enabling deterministic real-time performance for time-critical tasks such as USB packet handling and ADC sampling control in the LPC11U68JBD48K.

Does the LPC11U68JBD48K support USB device functionality without an external crystal?

Yes, the LPC11U68JBD48K supports XTAL-less low-speed USB device enumeration using its internal precision IRC oscillator. This eliminates the need for a 12 MHz external crystal in USB device mode, reducing bill-of-materials cost and PCB layout complexity. Full-speed USB operation still requires the on-chip PHY and proper termination, but the LPC11U68JBD48K's integrated USB controller handles protocol stack offload independently of external timing sources.

How many ADC channels does the LPC11U68JBD48K support, and what is its resolution?

The LPC11U68JBD48K integrates a single 12-bit successive-approximation ADC with up to 8 input channels in the LQFP48 package. It supports sample rates up to 2 Msamples/s and includes dual independent conversion sequences with internal and external trigger options. This ADC capability is fully documented for the LPC11U68JBD48K variant in NXP's Rev. 1.5 datasheet and enables high-fidelity analog signal acquisition for applications like battery monitoring or sensor interfacing.

What debug interface does the LPC11U68JBD48K support?

The LPC11U68JBD48K supports Serial Wire Debug (SWD) as the primary debug interface, accessible via SWDIO (pin 37) and SWCLK (pin 28) in the LQFP48 package. JTAG boundary scan is also supported for test and validation. Both interfaces are enabled by default and require no external configuration; SWD is recommended for development due to its 2-pin efficiency and full debug functionality - including flash programming, real-time variable inspection, and breakpoint control - for the LPC11U68JBD48K.

What is the purpose of the VBAT pin on the LPC11U68JBD48K?

The VBAT pin (pin 47) on the LPC11U68JBD48K supplies backup power to the RTC and associated backup registers during main power loss. When connected to a coin cell or supercapacitor, it maintains accurate timekeeping and preserves critical data across power cycles. This function is explicitly defined for the LPC11U68JBD48K in NXP's datasheet and is essential for applications requiring uninterrupted RTC operation, such as data loggers or security systems relying on time-stamped events.