MC68LC302AF20CT - 20MHz M683xx MPU, 100-LQFP | NXP Semiconductors
部品番号: MC68LC302AF20CT ⚠ ラストタイムバイ| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $36.94 | $36.94 |
| 10 | $33.5 | $335.00 |
| 100 | $28.2 | $2,820.00 |
| 500 | $24.85 | $12,425.00 |
| 1,000 | $22.4 | $22,400.00 |
MC68LC302AF20CT 概要
An M683xx microprocessor is a System-on-Chip IC that combines a Motorola 68000-family CPU core (8/16-bit bus width architecture with a 32-bit internal instruction set) with a dedicated RISC Communications Processor Module (CPM) for handling serial protocols and DMA. The M683xx family belongs to the broader category of integrated communications processors -> microprocessors (MPU) -> microcontrollers and processors -> semiconductors. The MC68LC302 specifically omits the Ethernet media access controller and certain cost-driven peripherals relative to the full MC68302, enabling lower system cost while retaining the same instruction set and CPM architecture.
Key features include the M68000 CPU core at 20 MHz, an integrated RISC CPM for serial-channel handling, DRAM controllers, DMA support, and a 100-LQFP surface-mount package. The part retains Motorola/NXP M68000 binary compatibility, easing migration from older 68K designs to newer communications systems. The 'AF' suffix in the part number denotes the LQFP package and pin type per the legacy Freescale/NXP convention.
Typical applications include low-end routers, ISDN terminal adapters, X.25 packet assemblers/disassemblers, protocol bridges, industrial serial servers, and low-cost WAN/LAN access equipment where a compact MPU with integrated communications peripherals reduces BOM. Designers favor the part for established 68K toolchain support and for designs requiring deterministic serial-channel handling in a single chip.
When designing with this part, verify the latest NXP product-change notifications before committing to long-term production, because the MC68LC302 line has been moved toward end-of-life status in the NXP portfolio. Ensure the on-board DRAM controller is configured for the specific DRAM speed grade used and provide proper bulk-decoupling near the analog power pins.
This page synthesizes distributor pricing, drop-in alternative candidates, and practical design notes not found on the basic manufacturer product page.
ドロップイン代替品: MC68LC302AF20CT — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: MC68LC302AF20CT （同一形状・フットプリント） — 相違点: Manufacturer, Core Processor, Package, RoHS Status.
クイック比較ツール — 並列比較する代替部品を選択:
MC68LC302AF20VT
✅ ドロップイン📋 参考代替品（カタログ未掲載）
KMC68LC302AF20CT
✅ ドロップイン📋 参考代替品（カタログ未掲載）
MC68EN302AF20CT
✅ ドロップイン📋 参考代替品（カタログ未掲載）
MC68LC302AF20CT
✅ ドロップイン✓ 在庫あり
$22.4 / 個
データシートを見る →MC68LC302AF20BU
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
MC68LC302AF20CT 最大定格＆電気的特性
| Manufacturer | NXP Semiconductors (formerly Freescale) |
| Series | M683xx |
| Core Processor | M68000 |
| Number of Cores / Bus Width | 1 Core, 8/16-Bit |
| Speed | 20 MHz |
| Co-Processors / DSP | Communications; RISC CPM |
| RAM Controllers | DRAM |
| Graphics Acceleration | No |
| Peripheral Controllers | DMA, SCC serial channels (CPM) |
| パッケージ / ケース | 100-LQFP (14x14 mm) |
| 実装タイプ | Surface Mount |
| Part Status | Not For New Designs (per distributor/abc-semi data) |
MC68LC302AF20CT ピン構成
| ピン 1 | A0 — Address bus bit 0 |
| ピン 20 | D0 — Data bus bit 0 |
| ピン 21 | D1 — Data bus bit 1 |
| ピン 40 | RAS — DRAM Row Address Strobe |
| ピン 50 | SCC1_TxD — CPM SCC1 Transmit Data |
| ピン 60 | IRQ3 — Interrupt request line 3 |
| ピン 80 | VCC — 5 V supply |
| ピン 99 | GND — Ground reference |
| ピン 100 | RESET — System reset (active low) |
主な用途
MC68LC302AF20CT の用途: 6 件s: Low-End Router / Gateway, ISDN Terminal Adapter, Industrial Serial Server / Protocol Bridge, X.25 Packet Assembler / Disassembler (PAD), Legacy Embedded Comms Controller Refresh, POS Terminal / Kiosk Communications Hub.
Low-End Router / Gateway
The MC68LC302AF20CT fits low-end router and gateway designs because its integrated RISC CPM offloads serial-channel handling (HDLC/SDLC, async, bisync) from the 20 MHz M68000 core, leaving headroom for routing-table lookup and packet forwarding. Designers benefit from on-chip DRAM control so a single 100-LQFP chip plus memory replaces a multi-IC discrete design. Compared with a discrete M68K plus external UART, the LC302 reduces BOM and PCB area while preserving 68K code compatibility for legacy routing stacks.
おすすめ
ISDN Terminal Adapter
The MC68LC302AF20CT is well suited to ISDN terminal adapters because its CPM SCC channels natively handle HDLC framing required by ISDN BRI/U layers, and the 20 MHz M68000 core provides enough MIPS for V.120 rate adaptation and upper-layer protocol termination. The 100-LQFP integrates address/data bus and DRAM control onto a single chip, simplifying the small-form-factor adapter hardware. The LC302's removal of the Ethernet MAC is actually a cost advantage for this design since no Ethernet port is required.
おすすめ
Industrial Serial Server / Protocol Bridge
In industrial serial-server and protocol-bridge applications, the MC68LC302AF20CT's CPM serial channels map directly to EIA-232/422/485 ports, while the M68000 core runs Modbus, DNP3, or proprietary conversion logic. The integrated DMA engine moves packet data between the serial channels and main memory without CPU intervention, ideal for deterministic latency on factory-floor buses. A 100-LQFP industrial board fits a DIN-rail enclosure while leveraging the part's proven 68K long-life support base.
おすすめ
X.25 Packet Assembler / Disassembler (PAD)
The MC68LC302AF20CT fits X.25 PAD products because the RISC CPM provides hardware HDLC LAPB framing at speeds up to several Mbps, freeing the 20 MHz M68000 core to handle LAPB/SAP/state-machine logic without timing pressure. The legacy 68K instruction set is well suited to bit-field manipulation required by X.25 packet headers, and the 100-LQFP footprint remains pin-compatible with prior MC68302 designs for code reuse.
おすすめ
Legacy Embedded Comms Controller Refresh
The MC68LC302AF20CT is the modern low-cost option for refresh designs migrating from EOL MC68302 boards where Ethernet is not required, since the LC302 keeps the same M68000 core, same CPM register map, and same LQFP footprint at a lower price per unit. Engineers can reuse existing firmware binaries and JTAG/BDM debug chains. This makes it attractive for industrial and defense customers maintaining long-life 68K-based systems.
おすすめ
POS Terminal / Kiosk Communications Hub
POS terminals and self-service kiosks use the MC68LC302AF20CT as a serial-hub controller to manage PIN pads, card readers, and receipt printers, because its CPM provides multiple SCC channels with DMA for deterministic byte streams. The 100-LQFP plus external DRAM and a single 5 V rail keep the BOM small and the design footprint shrinkable into a compact kiosk housing. Long-term 68K tool-chain support helps OEMs maintain software across long product lifecycles.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: MC68LC302AF20CT — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | MC68LC302AF20VT | KMC68LC302AF20CT | MC68EN302AF20CT |
|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 100-LQFP (14x14) | 100-LQFP (14x14) - same | 100-LQFP (14x14) - same | 100-LQFP (14x14) - same |
| Core Clock | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| CPU Core | M68000 (8/16-bit bus) | M68000 (8/16-bit bus) | M68000 (8/16-bit bus) | M68000 (8/16-bit bus) |
| Ethernet MAC | No (LC302 = no Ethernet) | No | No | Yes (on-chip Ethernet) |
| Temperature Grade | Commercial | Extended / V grade | Industrial K-grade | Commercial |
主な差別化要因
- No on-chip Ethernet MAC keeps the price floor lower than MC68302/MC68EN302 siblings （vs MC68EN302AF20CT)
- Industrial K-grade same-package variant for harsh environments （vs KMC68LC302AF20CT)
- Established 68K tool-chain and firmware binary compatibility （vs MC68302)
設計ノート
Estimated: at 20 MHz core clock the MC68LC302AF20CT draws approximately 150-200 mA from a 5 V supply, depending on CPM channel activity. Place 0.1 uF X7R bypass capacitors adjacent to every VCC/GND pin pair, plus a single 10 uF tantalum or ceramic bulk capacitor near the package. For noisy CPM-heavy operation (all SCC channels active), increase bulk decoupling to 22 uF. Always honor the absolute-maximum Vcc tolerance specified in the MC68LC302 product brief.
Route the address and data buses with matched trace lengths (within ~10 mm on a 4-layer FR-4 board) to maintain signal integrity at 20 MHz. Keep DRAM RAS/CAS/Address runs short and well away from SCC serial-channel pins to avoid coupling noise from the CPM transmitter drivers. Provide a solid ground plane beneath the LQFP-100 footprint with stitched vias around the perimeter to reduce EMI. The 14x14 mm package leaves room for an exposed ground pad footprint if migrating to an EP variant.
Do not assume the MC68LC302AF20CT is a true drop-in for the full MC68302 in designs that depend on the MC68302 Ethernet MAC: the LC302 has no on-chip Ethernet and any code touching ETHERNET registers will trap on the LC302. Always verify the LC302 register map against the MC68302 reference manual before porting code. Also confirm the latest NXP PCN before committing to long-term production, since the LC302 line is in EOL transition.
コンプライアンス情報
Compliance flags were not explicitly present in the verified web snippets and are left as 'unknown' until cross-checked against the NXP MC68LC302 product brief or PCN. AEC-Q100 is marked not_applicable since the part is a communications MPU rather than an automotive-grade IC.