Intel KU82308-20

The Intel 82308 works with the complementary 82309 Address Bus Controller to coordinate data movement between a microprocessor, DMA, memory and the Micro Channel bus. It generates control for Micro Channel memory and I/O cycles in 80386 and 80386SX designs. It is not a CPU or a complete bus chipset on its own.

• Supports 8-, 16- and 32-bit Micro Channel transfers.
• Generates control for external byte-swap and data-alignment logic.
• Provides an optional hardware-enforced I/O recovery mechanism.
• Includes an 82385 cache-controller interface for supported 80386 systems.
• Uses Intel CHMOS technology and a 100-pin PQFP family package.

Intel describes bus-cycle control, data conversion and alignment outputs, command recovery and cache-interface signals. The 82308 is paired with 82309 address control in the Intel Micro Channel peripheral family. The original document provides separate AC timing columns for 16-, 20- and 25-MHz kit configurations; the catalog -20 suffix suggests the 20-MHz class but exact KU ordering has not been independently verified.

Intel specifies a 100-pin plastic quad flat package for the 82308 family and refers to package specification 231369. The catalog says 100-QFP while distributor summaries say 100-PQFP. The exact local register mapping is unverified and candidate 100-QFP.jpg is absent. Validate the Intel mechanical drawing, pin-one position, pitch and lot before soldering.

Assembly checks

• Inspect all gull-wing leads.
• Confirm 100-pin outline and pin-one orientation.
• Compare actual footprint with controlled dimensions.

The Intel data sheet identifies processor-side command and status inputs, Micro Channel command outputs, data-width/alignment controls, RSEL recovery controls, SCLK, RESET and optional cache-related signals. Signal polarity and exact pin assignments must be taken from the original numbered pin table; this functional summary is not a wiring diagram.

Use the controlled Intel AC and DC tables for board design; the kit timing column alone does not qualify a supplied KU82308-20 lot.

No internal alternate is linked or qualified. Other 82308 grades or the 82309 companion have different timing or functions and should not be treated as drop-in replacements. Confirm processor, cache, DMA, package and bus timing before any substitution.

Intel authored the archival 82308 Micro Channel Bus Controller advance-information data sheet, documenting family functions, 100-pin package and 16-/20-/25-MHz kit timing tables. The family documentation supports the functional description, while exact KU82308-20 lot and order-code provenance still require confirmation.

• Maintenance of legacy 80386 Micro Channel-compatible motherboards.
• Bus-control replacement in qualified 82308/82309 chipset designs.
• Existing systems with external byte-swap and cache-interface logic.

Inspect full markings, date code, lead finish and provenance. The catalog lists 2,040 units at USD 40.00, MOQ seven, no tier ladder. An exact-code DigiKey/Rochester index lists 2,040 units at approximately USD 49.23 at quantity six. These commercial terms differ, and the index is not a dated direct quote; no catalog price or inventory field has been changed.

Keep this product in manual review and noindex until the exact order-code timing, lot traceability, 100-pin package registration and local JPG are confirmed, and stock and price are reconciled against a dated direct supplier quote. Do not publish before all gates pass.