NXP Semiconductors LPC51U68JBD64QL

Overview

LPC51U68JBD64QL from NXP Semiconductors is a 32-bit ARM Cortex-M0+ microcontroller designed for embedded control with crystal-less USB device operation. It integrates 256 KB flash, 96 KB SRAM (64 KB main + 32 KB SRAMX), a 12-bit 5.0 Msamples/sec ADC with 12 input channels, and eight software-configurable Flexcomm interfaces supporting USART/I2C/SPI/I2S. It targets low-power industrial sensing and USB-connected edge nodes.

For engineers reviewing the LPC51U68JBD64QL datasheet, LPC51U68JBD64QL pinout, LPC51U68JBD64QL application, or LPC51U68JBD64QL equivalent, key selection criteria include its 150 MHz CPU frequency, flexible peripheral routing via Flexcomm, ultra-low-power wake-up capability from deep power-down using the Micro-tick Timer, and pin-function compatibility with LPC5410x/LPC5411x in LQFP64.

Technical Context

The LPC51U68JBD64QL implements an ARM Cortex-M0+ core with single-cycle multiplier and NVIC, operating up to 150 MHz using internal FRO (48/96 MHz) or system PLL. Its clocking architecture includes dedicated fractional rate generators per Flexcomm interface and independent RTC domain with 1 ms wake-up resolution.

Digital I/O is organized across two GPIO ports (PIO0/PIO1), with up to 48 pins supporting configurable pull-up/pull-down, open-drain, and input inverters. Each Flexcomm interface includes FIFO and supports multiple protocols simultaneously-e.g., FC6 and FC7 provide full I2S with WS/CLK/DATA routing-while SCTimer/PWM enables complex state-driven waveform generation with 10 events and 10 states.

Key Specifications

Pinout & Package

LPC51U64JBD64QL is housed in a plastic LQFP64 package (10 × 10 × 1.4 mm, SOT314-2) with exposed pad for thermal performance and standard 0.5 mm pitch. All 64 pins are electrically defined; pin 1 index is marked by a corner notch or dot.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LPC54102JBD64, the LPC51U68JBD64QL offers lower power and crystal-less USB at the expense of FPU; compared with LPC55S06JBD64, it trades security extensions for cost-sensitive deployments where TrustZone is unnecessary.

Availability

LPC51U68JBD64QL is available at Aetrix Electronics and suitable for industrial sensor nodes, USB human interface devices, smart home gateways, and low-cost PLC I/O modules requiring stable component supply, long-term lifecycle assurance, and consistent parametric performance.

Supply support for LPC51U68JBD64QL 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 leader specializing in secure connectivity solutions for automotive, industrial, and IoT applications, with over 50 years of innovation in microcontrollers and embedded systems.

The LPC51U68 product line targets cost-optimized, low-power embedded control with integrated USB and flexible serial interfaces - designed specifically for resource-constrained edge devices needing high peripheral integration without sacrificing efficiency.

FAQ

What is the maximum operating frequency of the LPC51U68JBD64QL?

The LPC51U68JBD64QL operates at up to 150 MHz using its ARM Cortex-M0+ core. This frequency is achieved via the internal factory-trimmed FRO oscillator (96 MHz output) or system PLL, both supporting full-speed execution without external high-frequency crystals. The core maintains deterministic interrupt latency and single-cycle multiply performance across this range.

Does the LPC51U68JBD64QL support crystal-less USB operation?

Yes, the LPC51U64JBD64QL supports crystal-less USB 2.0 full-speed device mode using its on-chip PHY and software-based timing calibration. This eliminates the need for an external 12 MHz crystal, reducing bill-of-materials cost and PCB area - a key feature confirmed in NXP Technical Note TN00035 and the LPC51U68 datasheet Rev. 1.5.

How many ADC channels does the LPC51U68JBD64QL have, and what is its sampling rate?

The LPC51U68JBD64QL integrates a 12-bit successive-approximation ADC with 12 input channels and a maximum sampling rate of 5.0 million samples per second. It supports two independent conversion sequences and internal triggering from timers or external signals, enabling high-fidelity sensor data acquisition without external oversampling circuitry.

Is the LPC51U68JBD64QL pin-compatible with other NXP microcontrollers?

Yes, the LPC51U68JBD64QL is pin-function compatible with LPC5410x and LPC5411x devices in the same LQFP64 package. This means identical pin assignments for GPIO, peripherals, power, and debug interfaces - allowing direct PCB reuse in designs targeting migration or feature scaling, provided firmware accounts for architectural differences.

What power modes does the LPC51U68JBD64QL support, and how does wake-up work?

The LPC51U68JBD64QL supports sleep, deep-sleep, and deep power-down modes. Wake-up sources include RTC alarm, USART/SPI/I2C activity (as slave), GPIO interrupts, and the Micro-tick Timer - which runs from the watchdog oscillator and achieves <10 µs wake-up latency while consuming ~1 µA, ideal for battery-powered applications.