NXP Semiconductors MC9328MX21SCVM

Overview

MC9328MX21SCVM from NXP Semiconductors (formerly Freescale) is an ARM926EJ-S™-based microprocessor for portable handheld and embedded multimedia applications. It operates at 266 MHz, integrates LCD/SLCD controllers, USB On-The-Go, dual MMC/SD host controllers, NAND Flash controller with hardware ECC, and SDRAM interface - enabling full-featured PDA, industrial HMI, and connected terminal designs.

For engineers reviewing the MC9328MX21SCVM datasheet, MC9328MX21SCVM pinout, MC9328MX21SCVM application, or MC9328MX21SCVM equivalent, key selection criteria include its -40°C to +85°C industrial temperature rating, 289-pin MAPBGA (0.8 mm pitch, 17 mm × 17 mm), ARM926EJ-S core with Java acceleration, and integrated peripheral set supporting display, storage, and connectivity without external glue logic.

Technical Context

The MC9328MX21SCVM implements a 32-bit ARM926EJ-S core with MMU, 16 KB instruction and 16 KB data caches, and Smart Speed power management. Its memory subsystem includes dedicated SDRAMC (supporting up to 256 MB), WEIM for NOR/PSRAM expansion, and NFC with on-the-fly ECC for NAND Flash.

Peripherals are tightly integrated: dual SSI modules configurable as I²S or AC97, two CSPI interfaces, three UARTs (with IrDA/FIRI support), I²C, 1-Wire, PWM, RTC, watchdog, and three 32-bit general-purpose timers. All are mapped to a shared 289-pin MAPBGA package with extensive signal multiplexing managed via FMCR registers.

Key Specifications

Pinout & Package

The MC9328MX21SCVM is housed in a 289-pin MAPBGA (0.8 mm pitch, 17 mm × 17 mm) package. Pin functions are highly multiplexed across 12 functional domains including EIM, SDRAM, USB, LCD, SLCDC, NAND, PCMCIA, CSPI, UART, SSI, I²C, and JTAG. Signal assignment is defined in Section 4 of the official datasheet (Rev. 1.3), with critical boot pins (BOOT[3:0]), reset (RESET_IN/RESET_OUT), and clock inputs (EXTAL26M, EXTAL32K) requiring strict termination per design guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with the MC9328MX21SCVM, the i.MX27 offers higher throughput for media tasks but increases package size and power, while the i.MX31 shifts to ARM11 architecture with stronger security - making the MC9328MX21SCVM optimal for cost-sensitive, display-intensive industrial terminals needing proven long-term availability and minimal thermal design overhead.

Availability

MC9328MX21SCVM is available at Aetrix Electronics and suitable for industrial HMI, portable medical instrumentation, and ruggedized field data collection requiring stable component supply, extended temperature operation, and long-lifecycle support.

Supply support for MC9328MX21SCVM 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 focused on secure connectivity solutions for automotive, industrial, and IoT markets, formed from the spin-off and acquisition of Freescale Semiconductor in 2015.

The i.MX21 series was designed specifically for cost-optimized, power-efficient portable multimedia and industrial human-machine interface applications - emphasizing integrated display, storage, and connectivity with minimal external components.

FAQ

What is the maximum SDRAM capacity supported by the MC9328MX21SCVM?

The MC9328MX21SCVM SDRAM Controller (SDRAMC) supports up to 256 MB of external SDRAM. This is achieved using 4 banks × 13-row × 10-column addressing with 16-bit or 32-bit data bus width. The controller handles refresh, precharge, and burst modes autonomously, and the MC9328MX21SCVM datasheet specifies timing parameters for 133 MHz SDRAM operation under industrial temperature conditions.

Does the MC9328MX21SCVM support booting directly from NAND Flash?

Yes, the MC9328MX21SCVM supports NAND Flash boot via its integrated NAND Flash Controller (NFC) with hardware ECC. When BOOT[3:0] is configured for NAND mode, the ROM bootloader initializes the NFC, reads the first 4 KB from NAND (including spare area), verifies ECC, and loads the initial firmware into internal SRAM. This eliminates need for external boot ROM or FPGA configuration logic.

How does the Smart LCD Controller (SLCDC) differ from the standard LCD Controller (LCDC) in the MC9328MX21SCVM?

The SLCDC in the MC9328MX21SCVM provides dedicated timing and control signals (PS, CLS, REV, SPL_SPR) optimized for Sharp HR-TFT panels, enabling direct connection without external timing generators. In contrast, the LCDC delivers generic 18-bit RGB/TFT output. Both share LD[15:0] pins, but SLCDC uses alternate multiplexing on USB/SD signals - requiring careful pin assignment to avoid conflict in designs using both interfaces.

What are the factory test pins on the MC9328MX21SCVM, and how should they be handled in production designs?

The MC9328MX21SCVM includes factory test pins including CLKMODE[1:0], OSC26M_TEST, EXT_48M, EXT_266M, and TEST_WB[4:0]. Per the datasheet, EXT_48M and EXT_266M must be tied to ground; CLKMODE[1:0] and OSC26M_TEST must be left unconnected; TEST_WB[2:0] may be used as GPIO or keypad signals if enabled via FMCR, otherwise configured as pulled-up inputs and left floating. These pins have no user functionality.

Can the MC9328MX21SCVM simultaneously operate USB OTG and USB Host1 functions?

No - the MC9328MX21SCVM shares physical transceiver resources between USB OTG (USBG_*) and USB Host1 (USBH1_*). USBG_RXDP/USBG_RXDM and USBH1_RXDP/USBH1_RXDM are multiplexed on the same pins, as are transmit and control signals. Only one USB function (OTG or Host1) can be active at a time; dual-host capability requires USBH2, which is implemented separately with dedicated pins and supports simultaneous operation with OTG or Host1.