NXP Semiconductors LPC1785FBD208,551

Overview

LPC1785FBD208 from NXP Semiconductors is a 32-bit ARM Cortex-M3 microcontroller designed for high-integration embedded systems with low power dissipation. It operates at up to 120 MHz, integrates 256 kB flash, 80 kB SRAM (64 kB main + 16 kB peripheral), and 4032-byte EEPROM, and supports USB Device/Host/OTG, five UARTs, dual CAN, and an 8-channel 12-bit ADC - enabling use in industrial motor control and communications gateways.

For engineers reviewing the LPC1785FBD208 datasheet, LPC1785FBD208 pinout, LPC1785FBD208 application, or LPC1785FBD208 equivalent, key selection criteria include its LQFP208 package, absence of Ethernet and LCD controller (vs. LPC1788), 32-bit ARM Cortex-M3 core with MPU and NVIC, and support for SD/MMC, QEI, and motor control PWM - critical for real-time motion control and protocol-bridging designs.

Technical Context

The LPC1785FBD208 implements a Harvard-architecture ARM Cortex-M3 core with 3-stage pipeline, integrated Memory Protection Unit (MPU) supporting eight regions, and Nested Vectored Interrupt Controller (NVIC). Its multilayer AHB matrix enables concurrent access by CPU, USB, GPDMA, and peripherals without arbitration delay unless contending for the same slave.

System-level features include dual PLLs (one for CPU, one dedicated for USB), RTC with 20-byte battery-backed registers and event recorder, and a General Purpose DMA controller supporting transfers across UART, SSP, I2C, ADC, DAC, timers, GPIO, and memory-to-memory operations - all accessible via AHB or APB buses with split-bus optimization.

Key Specifications

Pinout & Package

LPC1785FBD208 is housed in a plastic low-profile quad flat package (LQFP208) with 208 leads, body size 28 × 28 × 1.4 mm (SOT459-1), rated for −40 °C to +85 °C operation and single 3.3 V supply (2.4–3.6 V).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LPC1786FBD208, LPC1785FBD208 removes Ethernet and LCD IP to reduce cost and power, while retaining SD/MMC and QEI; versus LPC1776FBD208, it adds SD/MMC and QEI for data-intensive and motor-control applications - making LPC1785FBD208 the optimal balance for industrial gateways requiring storage and position feedback.

Availability

LPC1785FBD208 is available at Aetrix Electronics and suitable for industrial motor control, multi-protocol gateways, and medical imaging subsystems requiring stable component supply and long-term lifecycle support.

Supply support for LPC1785FBD208 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 deep expertise in ARM-based microcontrollers and edge processing.

The LPC178x/7x product line targets high-performance, low-power embedded control applications - delivering integrated peripherals, real-time responsiveness, and robust debug infrastructure for complex industrial and medical systems.

FAQ

What is the maximum operating frequency of the LPC1785FBD208?

The LPC1785FBD208 operates at a maximum CPU frequency of 120 MHz, achieved using its on-chip PLL driven by either the internal 12 MHz RC oscillator (trimmed to ±1%) or an external crystal (1–25 MHz). This frequency is sustained across the full industrial temperature range (−40 °C to +85 °C) under 3.3 V supply (2.4–3.6 V), with flash accelerator ensuring zero-wait-state execution.

Does the LPC1785FBD208 include Ethernet or LCD controller functionality?

No, the LPC1785FBD208 does not include Ethernet MAC or LCD controller hardware. Per Table 2 of the datasheet, Ethernet is marked "N" and LCD is marked "N" for this variant. These peripherals are present in higher-tier members like LPC1788FBD208 but intentionally omitted in LPC1785FBD208 to optimize cost and power for applications that do not require them.

How much SRAM is available on the LPC1785FBD208, and how is it organized?

The LPC1785FBD208 provides 80 kB of total on-chip SRAM: 64 kB of main SRAM directly connected to the CPU's local code/data bus for high-speed zero-wait-state access, and one 16 kB peripheral SRAM block accessible via AHB for DMA and peripheral buffering. Unlike LPC1788, it does not include a second 16 kB peripheral SRAM block.

Can the LPC1785FBD208 support SD/MMC card interfacing?

Yes, the LPC1785FBD208 supports SD/MMC memory card interfacing as confirmed in Table 2 of the datasheet (SD/MMC column = "Y"). It provides dedicated SD_CLK, SD_CMD, and SD_DAT[0–3] signals, with SD_PWR control on P0[21], enabling direct connection to compliant cards for firmware logging, configuration storage, or media playback.

What debug interfaces are supported by the LPC1785FBD208?

The LPC1785FBD208 supports JTAG test/debug, Serial Wire Debug (SWD), and Serial Wire Trace (SWO) interfaces. It also includes an Embedded Trace Macrocell (ETM) for real-time instruction trace and boundary scan for board-level testing - all accessible via standard ARM-compliant debug probes without requiring external trace pods.