MC68B21CP-G - Peripheral Interface I/O Expander | Rochester Electronics
MPN: MC68B21CP-G ✓ AktifMC68B21CP-G Ringkasan
An I/O expander is an interface IC that adds parallel input or output lines to a processor or programmable bus controller. In the broader hierarchy, an I/O expander belongs to interface ICs, then to integrated circuits and semiconductors. This distinction matters because the MC68B21 family was designed for systems in which a host processor required additional peripheral data lines without relying exclusively on the processor's native port resources. The MC68B21CP-G designation identifies a specific orderable member of that legacy interface family.
The available listings consistently classify MC68B21CP-G as an I/O expander and peripheral-interface IC. The Rochester Electronics record is shown as in stock, the LCSC record lists a price from $93.9371, and the Components-House result reports 863 pieces in stock. A separate Full Electronic listing reports an inventory quantity of 36,484 units. These figures come from different sellers and should not be interpreted as a single consolidated stock total. The product-status record from FPGACenter identifies the component as currently active in production.
MC68B21CP-G is relevant to repair, modernization, industrial-control, embedded-system, and legacy-computing projects that specifically call for this established peripheral-interface device. Because it belongs to an older MC68 processor-support ecosystem, system compatibility depends on the host bus, control-signal arrangement, logic levels, timing, and package footprint documented for the selected device revision. A PCB replacement is not automatically safe merely because another product is also called an I/O expander; the data bus, register behavior, address decoding, interrupt handling, and electrical timing must match.
The retrieved web material does not expose a complete manufacturer specification table, package drawing, pinout, timing diagram, or absolute maximum ratings. Consequently, those details remain unresolved rather than being inferred from similarly named devices. For new production, engineers should obtain the MC68B21 family documentation, confirm the exact package suffix, validate signal compatibility, and complete a system-level timing check before committing a substitute or alternate ordering code to the PCB.
This page consolidates the verified distributor identity, current price and availability signals, source links, sourcing context, and selection guidance for MC68B21CP-G. It separates confirmed listing data from unresolved engineering fields so engineers can rapidly assess legacy-system fit without treating generic I/O-expander specifications as part-specific facts.
Alternatif penggantian untuk MC68B21CP-G — paket yang sama, pin-pada-pin kompatibel. Bagian paket yang berbeda memerlukan kerja ulang PCB diabaikan.
MC68B21P
✅ Drop-In ⚠️ Spesifikasi Tidak Disahkan📋 Alternatif referensi (tidak dalam katalog)
MC68B21CL
✅ Drop-In ⚠️ Spesifikasi Tidak Disahkan📋 Alternatif referensi (tidak dalam katalog)
MC68B21C
✅ Drop-In ⚠️ Spesifikasi Tidak Disahkan📋 Alternatif referensi (tidak dalam katalog)
MC68B21CP-G Spesifikasi
| Product Type | I/O Expander |
| Device Family | MC68B21 peripheral interface family |
| Kategori | Integrated Circuits (ICs) / I/O Expanders |
| Interface Classification | Peripheral Interface A |
| Manufacturer | Rochester Electronics, LLC |
| Original Device Reference | Motorola MC68B21CP |
| Product Status | Active |
| Listed Unit Price | $93.9371 as of 2026-10-30 |
| Reported Stock | 863 pieces at Components-House; 36,484 units at Full Electronic |
MC68B21CP-G standard Diamant Konfigurasi Panduan
Konfigurasi pin untuk MC68B21CP-G (standard pakai pakai). Penomoran pin, fungsi, dan diagram koneksi ditetapkan dalam datasheet produsen. Lihatnya untuk footprint dan pedoman perpindahan paruh.
Tidak ada data diatribut pin yang tersedia untuk MC68B21CP-G.
Lihat ke: datasheet produk untuk konfigurasi pin penuh.
Aplikasi Umum
MC68B21CP-G cocok untuk 6 aplikasis: Legacy MC68 Processor Peripherals, Industrial Control System Repair, Embedded Instrument Control, Data Acquisition and Parallel Port Expansion, Legacy Communications Controller Support, Obsolete-System Component Replenishment.
Legacy MC68 Processor Peripherals
The MC68B21CP-G fits legacy MC68 processor systems that require the established MC68B21 peripheral-interface function rather than a generic modern GPIO device. Its verified identity as an MC68B21-family I/O expander allows a maintenance engineer to preserve the original processor ecosystem while replacing a failed interface component. The critical engineering task is to match the package, logic levels, register behavior, address decoding, and timing of the installed revision. Because the retrieved records do not publish those electrical details, the component should be qualified from the exact family documentation before production use.
Industrial Control System Repair
MC68B21CP-G is appropriate for repair and continuation of older industrial-control equipment whose controller relied on the MC68B21 peripheral interface. Active-production status and multiple distributor availability records make it more practical for maintenance procurement than assuming an undocumented modern equivalent will fit. However, industrial use also requires confirmation of operating temperature, noise immunity, supply limits, and long-term availability. The listed $93.9371 price as of October 30, 2026 should be weighed against the engineering risk of redesigning an embedded control board or changing its processor firmware.
Embedded Instrument Control
The MC68B21CP-G can support legacy embedded instrument designs that use an MC68-family host controller to operate external registers, lamps, relays, latches, or other peripheral logic. Retaining the original interface IC can minimize changes to control firmware and reduce board respin risk. An engineer must still confirm the device's exact I/O width, signal polarity, handshake timing, and supply requirements from the MC68B21CP datasheet. The verified distributor listings support sourcing the component, while the unavailable detailed timing and pin data prevent a complete first-article design from being released using listing snippets alone.
Data Acquisition and Parallel Port Expansion
MC68B21CP-G is relevant to legacy data-acquisition equipment that needs the MC68B21 peripheral interface to extend parallel control or input capability beyond the host processor's native resources. This is especially useful when preserving an existing board and its software is more valuable than adopting a modern bus-based expander. Compatibility assessment must include signal direction, address-select decoding, interrupt behavior, input thresholds, and output drive capability. The verified records identify the part as an I/O expander but do not reveal those parameters, so bench-level validation is necessary before reuse in new measurement equipment.
Legacy Communications Controller Support
MC68B21CP-G may be used in legacy communications or networking equipment where an MC68-family processor relies on the MC68B21 interface to manage peripheral control signals. The component's verified Peripheral Interface A classification and active sourcing status support repair-focused procurement. A modern serial expander may offer lower cost or smaller size, but it can require board changes and substantial firmware or hardware-interface adaptation. For drop-in repair, compare the candidate device pin by pin and verify timing and logic thresholds using the original system schematic and the applicable MC68B21 documentation.
Obsolete-System Component Replenishment
MC68B21CP-G is useful for replenishing inventory in systems that are otherwise serviceable but depend on a legacy MC68B21 interface IC. Rochester Electronics' active-production status and the availability reported by DigiKey, LCSC, AMPHEO, Components-House, and Full Electronic provide multiple sourcing paths. The reported stock quantities are seller-specific and were captured on October 30, 2026, so procurement teams should confirm current inventory before planning a large repair campaign. Schedule a controlled lifecycle plan because no detailed obsolescence roadmap, long-term supply commitment, or complete environmental specification was included in the retrieved data.
Data referensi engineering untuk MC68B21CP-G — pembandingan, panduan desain, dan informasi konformitas.
Panduan Pemilihan
Pembandingan dengan Alternatif
| Parameter Umum | Produk Ini | MC68B21P | MC68B21CL | MC68B21C |
|---|---|---|---|---|
| Product Type | I/O Expander | MC68B21-family peripheral-interface I/O expander | MC68B21-family peripheral-interface I/O expander | MC68B21-family peripheral-interface I/O expander |
| Brand | Rochester Electronics, LLC | Motorola | Motorola | Motorola |
| Interface Family | MC68B21 peripheral interface | MC68B21 peripheral interface | MC68B21 peripheral interface | MC68B21 peripheral interface |
Diferensiator Kunci
- Verified Rochester Electronics orderable designation (vsMC68B21P)
- Current multi-distributor availability (vsMC68B21CL)
- Explicit Peripheral Interface A classification (vsMC68B21C)
Catatan Desain
Do not treat every I/O expander as an equivalent to MC68B21CP-G. The replacement must preserve the complete host-interface behavior, including bus width, address selection, register definitions, interrupt or handshake signals, logic thresholds, timing, and package geometry. MAX7314ATG+ and R8A66021GP#R2 appeared in the cross-reference results, but the supplied snippets only establish that they are I/O expanders; they do not prove drop-in compatibility.
Before ordering a replacement, compare the exact MC68B21CP-G package drawing against the installed device and verify every physical pin. The supplied web records do not expose a verified pinout or package pin count for the -G ordering code, so this page deliberately publishes no reconstructed pin list. Use the original system schematic, the MC68B21 family documentation, and the Rochester ordering documentation together before applying power to a candidate device.
Validate the supply-voltage range, input thresholds, output drive, and power dissipation at the actual system operating conditions before using MC68B21CP-G in a new design. None of those electrical limits appears in the retrieved distributor snippets, and legacy interfaces may operate near the limits of older logic families. A successful replacement must match the host system's voltage domains and must not source excessive current into the peripheral bus.
If the peripheral bus is long, slow, or electrically noisy, reproduce the original driver's termination, pull-up, pull-down, and capacitive-loading arrangement. Confirm address-decode setup and hold timing, peripheral strobe width, and any interrupt acknowledgment sequence from the family documentation. These timing checks are more meaningful than generic I/O-expander comparisons because software written for the MC68B21 interface may depend on its established register and handshake behavior.
The price of $93.9371 and the stock quantities in the verified results are seller-specific snapshots captured on October 30, 2026. Do not combine the 863-piece Components-House quantity with Full Electronic's 36,484-unit inventory as though they represent one warehouse. Obtain current quotes and lead times directly from the selected supplier, and define an approved alternate only after package and electrical validation rather than relying on price or active-production language alone.
Informasi Konformitas
The retrieved distributor material does not provide substantiated RoHS, REACH, lead-free, halogen-free, or conflict-minerals declarations for MC68B21CP-G. AEC-Q100 is not applicable because this is a legacy peripheral-interface IC rather than an automotive-qualified device.
