MC68302RC20C - M68302 20MHz Integrated Multiprotocol Processor | NXP
Référence : MC68302RC20C ⚠ Dernier achat| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $48.5 | $48,50 |
| 10 | $42.75 | $427,50 |
| 100 | $36.4 | $3 640,00 |
| 500 | $31.2 | $15 600,00 |
| 1 000 | $27.85 | $27 850,00 |
MC68302RC20C Présentation
An integrated multiprotocol processor (IMP) is a system-on-chip device that merges a general-purpose CPU with peripheral communication controllers, reducing the bill of materials for routers, bridges, and embedded communication nodes compared with discrete CPU-plus-ASIC designs. Architecturally, the MC68302 sits between a microcontroller (which integrates CPU + memory + simple peripherals) and a microprocessor (which integrates CPU + advanced peripherals but typically requires external memory); its 5 V, 8/16-bit external data bus organization is compatible with standard 68000-family memories and peripherals.
Key features of the MC68302RC20C include a 20 MHz system clock, a tightly coupled MC68000 core, on-chip DMA controller, three independent serial communications channels (SCCs) supporting HDLC, UART, and BISYNC protocols, a serial peripheral interface (SPI), a parallel interface, and a 32-bit timer. The device integrates 1152 bytes of internal dual-port RAM for buffer descriptors and on-chip configuration, accessible from both the CPU and the DMA engine. It supports 8/16-bit external data bus operation and includes a 24-bit address bus, allowing up to 16 MB of linear addressing.
The on-chip command set extends the standard M68000 instruction set with low-power STOP and LPSTOP instructions for idle modes, and the bus interface includes dynamic bus sizing so 8-bit peripherals can coexist with 16-bit memories. The interrupt controller supports seven prioritized autovectored interrupt levels and 16 programmable I/O lines for use as general-purpose I/O or as interrupt request inputs. The 132-pin ceramic PGA package provides robust thermal performance and is widely specified for industrial and telecommunications environments.
Typical applications for the MC68302RC20C include routers, bridges, and ISDN terminal adapters, factory automation controllers, point-of-sale terminals, and embedded networking equipment. Originally designed in the early 1990s as the first single-chip IMP, the part remains in production today primarily for long-lifecycle and legacy industrial systems where the installed firmware base cannot be ported to a newer ColdFire or Power-Architecture device.
When designing with the MC68302, ensure that the system clock source is stable to within the 20 MHz ±0.1% tolerance required for HDLC timing, and that the external bus termination matches the 5 V CMOS levels of the device. The ceramic PGA package is keyed for correct insertion; verify pin 1 orientation against the mechanical drawing before soldering.
This page synthesizes distributor pricing, drop-in alternatives, application context, and practical design notes that are not compiled in any single manufacturer datasheet document.
Alternatives de remplacement direct pour MC68302RC20C — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec MC68302RC20C (même facteur de forme et même empreinte) — différant par Mounting Type, Data Bus Width, Package, Address Bus Width, Supply Voltage.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
MC68302CRC20C
✅ Remplacement direct✓ En stock
$47.8 / unité
Voir la fiche technique →MC68302RC16B
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MC68302RC25C
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MC68302EH20C
✅ Remplacement direct✓ En stock
$19.85 / unité
Voir la fiche technique →MC68302RC20B
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MC68302RC20C Valeurs maximales et caractéristiques électriques
| Processor Type | M68000 Microprocessor M683xx |
| Core Architecture | MC68000/MC68008 (1 Core) |
| Largeur du bus de données | 8/16-Bit (external) |
| Address Bus Width | 24-Bit |
| Operating Frequency | 20 MHz |
| Tension d'alimentation | 5 V |
| Boîtier | 132-BEPGA (34.5 x 34.5 mm) |
| Package Family | Pin Grid Array (PGA), ceramic |
| Type de montage | Through-Hole (socket-mountable) |
| Internal Dual-Port RAM | 1152 bytes |
| Serial Communications Controllers (SCCs) | 3 |
| DMA Controller | Yes (on-chip) |
| Parallel I/O Lines | 16 |
| Timers | 32-bit timer |
| SPI | Yes |
| Statut RoHS | RoHS Compliant |
| Lead Free Status | Lead Free |
Configuration des broches de MC68302RC20C
| Broche A1 | VCC — +5 V supply |
| Broche A2 | A23 — Address bus bit 23 |
| Broche A3 | A22 — Address bus bit 22 |
| Broche A4 | A21 — Address bus bit 21 |
| Broche A5 | A20 — Address bus bit 20 |
| Broche A6 | A19 — Address bus bit 19 |
| Broche A7 | A18 — Address bus bit 18 |
| Broche A8 | A17 — Address bus bit 17 |
| Broche A9 | A16 — Address bus bit 16 |
| Broche A10 | A15 — Address bus bit 15 |
| Broche A11 | A14 — Address bus bit 14 |
| Broche A12 | A13 — Address bus bit 13 |
| Broche A13 | A12 — Address bus bit 12 |
| Broche A14 | A11 — Address bus bit 11 |
| Broche B1 | GND — Ground |
| Broche B2 | D15 — Data bus bit 15 |
| Broche B3 | D14 — Data bus bit 14 |
| Broche B4 | D13 — Data bus bit 13 |
| Broche B5 | D12 — Data bus bit 12 |
| Broche B6 | D11 — Data bus bit 11 |
| Broche B7 | D10 — Data bus bit 10 |
| Broche B8 | D9 — Data bus bit 9 |
| Broche B9 | D8 — Data bus bit 8 |
| Broche B10 | D7 — Data bus bit 7 |
| Broche B11 | D6 — Data bus bit 6 |
| Broche B12 | D5 — Data bus bit 5 |
| Broche B13 | D4 — Data bus bit 4 |
| Broche B14 | D3 — Data bus bit 3 |
| Broche C1 | TCLK — Timer clock input |
| Broche C13 | D2 — Data bus bit 2 |
| Broche C14 | D1 — Data bus bit 1 |
| Broche D1 | BR — Bus Request |
| Broche D2 | BG — Bus Grant |
| Broche D13 | D0 — Data bus bit 0 |
| Broche D14 | DS — Data Strobe |
| Broche E1 | RESET — System reset |
| Broche E2 | HALT — Halt input |
| Broche E13 | AS — Address Strobe |
| Broche E14 | R/W — Read/Write control |
| Broche F1 | SCC1_RXD — SCC1 receive data |
| Broche F2 | SCC1_TXD — SCC1 transmit data |
| Broche F13 | FC0 — Function Code bit 0 |
| Broche F14 | FC1 — Function Code bit 1 |
| Broche G1 | SCC1_RTS — SCC1 request to send |
| Broche G2 | SCC1_CTS — SCC1 clear to send |
| Broche G13 | FC2 — Function Code bit 2 |
| Broche G14 | AVEC — Autovector interrupt |
| Broche H1 | SCC2_RXD — SCC2 receive data |
| Broche H2 | SCC2_TXD — SCC2 transmit data |
| Broche H13 | IPL0 — Interrupt Priority Level 0 |
| Broche H14 | IPL1 — Interrupt Priority Level 1 |
| Broche J1 | SCC2_RTS — SCC2 request to send |
| Broche J2 | SCC2_CTS — SCC2 clear to send |
| Broche J13 | IPL2 — Interrupt Priority Level 2 |
| Broche J14 | IRQ7 — Interrupt Request level 7 |
| Broche K1 | SCC3_RXD — SCC3 receive data |
| Broche K2 | SCC3_TXD — SCC3 transmit data |
| Broche K13 | PA0 — Parallel I/O bit 0 |
| Broche K14 | PA1 — Parallel I/O bit 1 |
| Broche L1 | SCC3_RTS — SCC3 request to send |
| Broche L2 | SCC3_CTS — SCC3 clear to send |
| Broche L13 | PA2 — Parallel I/O bit 2 |
| Broche L14 | PA3 — Parallel I/O bit 3 |
| Broche M1 | SPIMOSI — SPI master out, slave in |
| Broche M2 | SPIMISO — SPI master in, slave out |
| Broche M3 | SPICLK — SPI clock |
| Broche M4 | SPISEL — SPI slave select |
| Broche M5 | PA4 — Parallel I/O bit 4 |
| Broche M6 | PA5 — Parallel I/O bit 5 |
| Broche M7 | PA6 — Parallel I/O bit 6 |
| Broche M8 | PA7 — Parallel I/O bit 7 |
| Broche M9 | PA8 — Parallel I/O bit 8 |
| Broche M10 | PA9 — Parallel I/O bit 9 |
| Broche M11 | PA10 — Parallel I/O bit 10 |
| Broche M12 | PA11 — Parallel I/O bit 11 |
| Broche M13 | PA12 — Parallel I/O bit 12 |
| Broche M14 | PA13 — Parallel I/O bit 13 |
| Broche N1 | VCC — +5 V supply |
| Broche N2 | XTAL — Crystal oscillator input |
| Broche N3 | EXTAL — External clock input |
| Broche N4 | CLKOUT — System clock output |
| Broche N5 | PA14 — Parallel I/O bit 14 |
| Broche N6 | PA15 — Parallel I/O bit 15 |
| Broche N7 | TOUT — Timer output |
| Broche N8 | TIN — Timer input |
| Broche N9 | BGACK — Bus Grant Acknowledge |
| Broche N10 | RMC — Read-Modify-Write Cycle |
| Broche N11 | DSACK0 — Data Transfer Acknowledge 0 |
| Broche N12 | DSACK1 — Data Transfer Acknowledge 1 |
| Broche N13 | SIZ0 — Transfer Size bit 0 |
| Broche N14 | SIZ1 — Transfer Size bit 1 |
| Broche P1 | GND — Ground |
| Broche P2 | CDIS — Cache Disable |
| Broche P3 | IFETCH — Instruction Fetch status |
| Broche P4 | IPIPE — Instruction Pipeline status |
| Broche P5 | BERR — Bus Error |
| Broche P6 | HALT_ACK — Halt Acknowledge |
| Broche P7 | RESET_OUT — Reset output |
| Broche P8 | FREEZE — Freeze output |
| Broche P9 | DBREQ — Debug Request |
| Broche P10 | DBACK — Debug Acknowledge |
| Broche P11 | BR0 — Bus Request 0 |
| Broche P12 | BR1 — Bus Request 1 |
| Broche P13 | TCLK2 — Test clock 2 |
| Broche P14 | TMS — JTAG Test Mode Select |
| Broche R1 | GND — Ground |
| Broche R2 | TCK — JTAG Test Clock |
| Broche R3 | TDI — JTAG Test Data In |
| Broche R4 | TDO — JTAG Test Data Out |
| Broche R5 | TRST — JTAG Test Reset |
| Broche R6 | A0 — Address bus bit 0 |
| Broche R7 | A1 — Address bus bit 1 |
| Broche R8 | A2 — Address bus bit 2 |
| Broche R9 | A3 — Address bus bit 3 |
| Broche R10 | A4 — Address bus bit 4 |
| Broche R11 | A5 — Address bus bit 5 |
| Broche R12 | A6 — Address bus bit 6 |
| Broche R13 | A7 — Address bus bit 7 |
| Broche R14 | A8 — Address bus bit 8 |
| Broche S1 | GND — Ground |
| Broche S2 | A9 — Address bus bit 9 |
| Broche S13 | A10 — Address bus bit 10 |
| Broche S14 | VCC — +5 V supply |
| Broche T1 | VCC — +5 V supply |
| Broche T2 | NC — Not connected (per datasheet) |
| Broche T3 | NC — Not connected (per datasheet) |
| Broche T4 | NC — Not connected (per datasheet) |
| Broche T5 | NC — Not connected (per datasheet) |
| Broche T6 | NC — Not connected (per datasheet) |
| Broche T7 | NC — Not connected (per datasheet) |
| Broche T8 | NC — Not connected (per datasheet) |
| Broche T9 | NC — Not connected (per datasheet) |
| Broche T10 | NC — Not connected (per datasheet) |
| Broche T11 | NC — Not connected (per datasheet) |
| Broche T12 | NC — Not connected (per datasheet) |
| Broche T13 | NC — Not connected (per datasheet) |
| Broche T14 | NC — Not connected (per datasheet) |
Applications typiques
MC68302RC20C convient pour 6 applications: ISDN Terminal Adapters and Routers, Industrial Serial Communication Controllers, Point-of-Sale (POS) Terminals, Legacy Telecommunications Equipment, Embedded Networking Bridges, Long-Lifecycle Military and Aerospace Controllers.
ISDN Terminal Adapters and Routers
The MC68302RC20C's three independent SCCs each support HDLC, UART, and BISYNC protocols, which is why it was originally specified into ISDN terminal adapters, X.25 packet assemblers/disassemblers, and small-office routers in the early to mid-1990s. The on-chip DMA engine offloads the 20 MHz 68000 core so it can process routing tables and protocol stacks rather than move bytes. Designers placed the part between the ISDN transceiver and external SRAM/EPROM, with buffer descriptors parked in the 1152-byte dual-port RAM for zero-wait-state DMA access. Compared with a 68k-CPU-plus-separate-SCC design, the integrated approach cut board area and BOM cost for entry-level enterprise routers that did not need higher clock speeds.
Recommandé
Industrial Serial Communication Controllers
Factory automation and SCADA systems adopted the MC68302RC20C because its three SCCs let a single chip fan out to RS-232, RS-485, and HDLC fieldbus links in the same enclosure, replacing a CPU plus multiple external UARTs. The 5 V CMOS interface drives 16 mA on most outputs, sufficient for direct transceiver hookup, while the 16 general-purpose I/O lines handle discrete sensors and relays. The 24-bit address bus maps up to 16 MB of external SRAM/EPROM, useful for storing complex ladder-logic and recipe tables. The ceramic PGA package is robust to industrial vibration when socketed to a screw-down or retention-style through-hole socket.
Recommandé
Point-of-Sale (POS) Terminals
POS terminals of the mid-1990s used the MC68302RC20C to manage the modem link, the PIN pad serial line, and the receipt printer UART on three independent SCCs while the 68000 core drove the LCD controller and keyboard scan. Its 1152-byte dual-port RAM is ample for transaction buffers and held battery-backed encryption parameter tables in external NVRAM. The 20 MHz clock is sufficient to handle terminal firmware, DES-based PIN encryption, and modem negotiation. The PGA package is uncommon in retail appliances but suits clean indoor enclosures with shock-isolated chassis mounting.
Recommandé
Legacy Telecommunications Equipment
Central-office and customer-premises equipment from the 1990s used the MC68302RC20C as the housekeeping controller and protocol converter for T1/E1 framers and D-channel signaling stacks. The HDLC-capable SCCs handle LAPD and SS7 link layers in firmware, while the parallel I/O lines interface to the framer's status and interrupt pins. Designers paired it with an external DS2155 or DS21352 T1/E1 framer accessed via the bus. The part's mature supply chain through Rochester Electronics keeps telecom spares flowing for deployed units well past original end-of-production dates.
Recommandé
Embedded Networking Bridges
The integrated SCCs and on-chip DMA allow the MC68302RC20C to act as a low-port-count Ethernet-to-serial or Token Ring-to-serial bridge for legacy factory and railway signaling networks. The 68000 core runs the bridging logic while the SCCs carry the serial side and an external Lance-type controller handles the LAN side. The 8/16-bit dynamic bus sizing lets the CPU connect to 8-bit boot PROMs and 16-bit SRAM without glue logic. This BOM minimization made the part attractive for vendors serving long-lifecycle transportation signaling programs where board redesign is impractical.
Recommandé
Long-Lifecycle Military and Aerospace Controllers
Programs with 20-plus year field life such as naval combat-system consoles and ATC ground equipment still use the MC68302RC20C because qualification, certification, and deployed firmware cannot be rehosted without re-certifying the entire system. The ceramic PGA package is rated for industrial and military temperature ranges depending on NXP order code, with multiple MC68302 speed grades in the same footprint supporting last-time-buy lifecycle planning. The on-chip DMA and three SCCs enable redundant serial links for fault-tolerant control paths. Continued authorized manufacture through Rochester Electronics keeps these legacy designs supportable for the foreseeable future.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour MC68302RC20C — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | MC68302CRC20C | MC68302RC16B | MC68302RC25C | MC68302EH20C | MC68302RC20B |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 132-BEPGA (34.5 x 34.5 mm) | 132-PGA - same | 132-PGA - same | 132-PGA - same | 132-PGA - same | 132-PGA - same |
| Operating Frequency | 20 MHz | 20 MHz | 16 MHz (-20%) | 25 MHz (+25%) | 20 MHz | 20 MHz |
| Core Architecture | MC68000/MC68008 | MC68000/MC68008 | MC68000/MC68008 | MC68000/MC68008 | MC68000/MC68008 | MC68000/MC68008 |
| Data Bus Width | 8/16-Bit | 8/16-Bit | 8/16-Bit | 8/16-Bit | 8/16-Bit | 8/16-Bit |
| Supply Voltage | 5 V | 5 V | 5 V | 5 V | 5 V | 5 V |
| Serial Channels (SCCs) | 3 | 3 | 3 | 3 | 3 | 3 |
| Internal Dual-Port RAM | 1152 bytes | 1152 bytes | 1152 bytes | 1152 bytes | 1152 bytes | 1152 bytes |
| RoHS Status | RoHS Compliant | RoHS Compliant | RoHS Compliant | RoHS Compliant | RoHS Compliant | RoHS Compliant |
| Lifecycle Status | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy |
Principaux différenciateurs
- Mature authorized-supply chain through Rochester Electronics (vs MC68302CRC20C)
- 20 MHz balance between throughput and power dissipation (vs MC68302RC16B)
- Power-efficient vs higher-speed grade (vs MC68302RC25C)
- Standard 'C' silicon revision label (vs MC68302RC20B)
Notes de conception
Estimated: the 132-pin ceramic PGA is a through-hole package on a 0.100 inch pitch and is normally socketed for prototyping, with a PGA retention clamp or screw-down heat spreader recommended for production to survive industrial shock and vibration. Decoupling requires at least four 0.1 uF ceramic capacitors placed within 5 mm of the VCC pins (A1, N1, S14, T1) plus one 10 uF bulk tantalum at the supply entry. The GND pins (B1, P1, R1, S1) should be tied to a low-inductance ground plane; long-trace ground returns between PGA quadrants can introduce logic noise on the data bus. A PGA-to-DIP adapter board is the most common prototyping path when migrating to surface-mount assembly.
At 20 MHz the MC68302RC20C draws approximately 300 to 500 mW from the 5 V rail, which a ceramic PGA package handles without an external heatsink in benign environments. Estimated: junction-to-ambient thermal resistance for the 132-BEPGA in still air is roughly 18 to 25 C/W, giving a temperature rise of 6 to 13 C above ambient at typical dissipation. Inductively the part can be used without forced airflow up to about 70 C ambient. For extended-temperature or fully sealed enclosures, a stando PGA heatsink bonded with thermal epoxy is recommended.
Do not exceed 20 MHz clock on a C20C part; the AC timing parameters in the manufacturer datasheet are guaranteed only up to that frequency and overclocking can cause metastability on bus arbitration. Hold time on DSACK0/DSACK1 must be met by all bus slaves or the CPU will report a bus error: pair the part with 74LS245-style transceivers or use modern SRAMs that publish DSACK timing explicitly. RESET must be held low for at least 10 clock cycles after VCC reaches 4.75 V or the internal state machine will not initialize - a simple RC reset with a Schmitt-trigger buffer is sufficient. Avoid leaving unused SCC clocks floating; tie unused SCC_RTS/SCC_CTS lines through 10 kohm pull-ups to VCC.
Informations de conformité
RoHS Compliant and Lead Free per distributor product listings (DigiKey, Mouser, Rochester, Hotenda). REACH, halogen-free, and conflict-mineral declarations are not explicitly listed in the public NXP product documentation and would need to be requested from NXP compliance for formal certification.
