MC68LC302PU20CT

Microprocessors Overview

The MC68LC302PU20CT is a low-cost integrated multiprotocol processor featuring a static M68000 core and a reduced pin count compared to the MC68302. It operates at 20 MHz with a 5V supply in a 100-pin Thin Quad Flat Pack (TQFP) package, suitable for commercial temperature ranges. The device integrates two serial communication controllers, three timers including a watchdog, an interrupt controller, and 1152 bytes of dual-port RAM. Key enhancements include a new Periodic Interrupt Timer (PIT), low-power standby modes, and on-chip PLL support for 32 kHz or 4 MHz crystals.

Microprocessors Feature Summary

• Integrates a static M68000 core supporting 8-bit or 16-bit system buses.
• Includes two full-duplex Serial Communication Controllers (SCCs) supporting HDLC/SDLC, UART, BISYNC, and transparent modes.
• Features enhanced low-power capabilities with standby modes wakeable via pins or PIT.
• Provides glueless interface to memory types such as EPROM, SRAM, Flash, and EEPROM.

Microprocessors Applications

• Low power and portable applications requiring extended battery life.
• Space-critical designs utilizing height-restricted form factors like PCMCIA cards.
• Systems requiring intelligent DMA-driven peripheral functions with serial channels.
• Applications needing multiprotocol serial communication without third SCC requirements.

Microprocessors Procurement Notes

Verify that the specific suffix CT corresponds to tape-and-reel packaging if required by assembly processes, as standard PU suffixes may indicate tray distribution. Confirm the operating voltage is strictly 5V for this variant. Ensure the commercial temperature range meets environmental specifications. Cross-reference the ordering number against current NXP documentation to confirm availability status and any potential product discontinuation notices.

Microprocessors Selection Notes

Select this component when the third serial channel of the MC68302 is unnecessary, allowing for cost reduction and smaller footprint. It is appropriate for designs prioritizing low power consumption through static core technology and programmable clock generation. Consider this part for embedded systems requiring robust serial protocol handling within a constrained 100-pin package environment.

Microprocessors Part Context

The MC68LC302 serves as a low-cost derivative of the MC68302 Integrated Multiprotocol Processor. It retains the core functionality while removing the third SCC and reducing external bus arbitration flexibility to accommodate a 100-pin package. This simplification targets applications where space and power efficiency are critical constraints over maximum bus master capability.

Microprocessors Replacement Considerations

The MC68302 is the primary functional predecessor but requires a larger 132-pin package and lacks the static core optimization. Direct substitution is not possible due to pin incompatibility. Designers must evaluate the loss of external bus mastership and the absence of the third serial controller when considering alternatives.

Microprocessors FAQ

How does the MC68LC302 differ from the MC68302 regarding serial controllers?

The MC68LC302 removes the third Serial Communication Controller (SCC3) and its baud rate generator, retaining only two independent full-duplex SCCs.

What low-power features are included in this processor?

It includes new low-power standby modes that can be exited via two specific pins or the Periodic Interrupt Timer (PIT), alongside a static core to reduce overall power budget.

Can external masters take control of the bus on the MC68LC302?

Normal bus arbitration for external masters is removed due to pin reduction. External masters can only maintain bus mastership using the HALT pin or in CPU disabled slave mode.