D8237AC-5 Direct Memory Access (DMA) Controller 5V 110mA IC DIP-40 (Wide)
The D8237AC-5 is a high-performance programmable Direct Memory Access (DMA) controller compatible with the industry-standard 8237A architecture. It provides four independent DMA channels that enable high-speed data transfers between memory and peripheral devices while reducing CPU workload. The controller supports advanced DMA functions including memory-to-memory transfers, auto-initialization, software DMA requests, programmable request and acknowledge polarity, and cascade expansion for larger DMA systems.
Designed for microprocessor-based systems, the D8237AC-5 operates as an intelligent bus controller that temporarily takes control of the system bus to perform data transfers. It supports Single, Block, Demand, and Cascade transfer modes, making it suitable for computers, industrial controllers, embedded systems, communication equipment, and legacy hardware designs. The device is housed in a 40-pin DIP package and operates with a clock frequency of up to 5MHz.
Features:
- Four independent DMA channels.
- Direct memory access operation.
- Memory-to-memory transfer capability.
- Auto-initialization support.
- Software DMA request capability.
- Programmable DREQ and DACK polarity.
- Address increment and decrement modes.
- Cascade expansion support.
- Single transfer mode.
- Block transfer mode.
- Demand transfer mode.
- Cascade transfer mode.
- Priority-based channel management.
- Built-in address and word count registers.
- Reduced CPU overhead during data transfers.
- Compatible with 8080, 8085, 8086, and 8088 systems.
Specifications:
| Parameter | Value |
|---|---|
| Model | D8237AC-5 |
| Device Type | Programmable DMA Controller |
| DMA Channels | 4 |
| Data Bus Width | 8-bit |
| Package | DIP-40 |
| Maximum Clock Frequency | 5 MHz |
| Maximum Transfer Rate | 1.6 MB/s |
| Operating Voltage | 5V ±5% |
| Operating Temperature | 0°C to 70°C |
| Storage Temperature | -65°C to +150°C |
| Power Dissipation | 1.5W Maximum |
| Technology | NMOS |
| Transfer Modes | Single, Block, Demand, Cascade |
| Address Registers | 4 Current + 4 Base |
| Word Count Registers | 4 Current + 4 Base |
Pinout:
| Pin | Name |
|---|---|
| 1 | I/OR |
| 2 | I/OW |
| 3 | MEMR |
| 4 | MEMW |
| 5 | READY |
| 6 | HLDA |
| 7 | ADDSTB |
| 8 | AEN |
| 9 | HRQ |
| 10 | CS |
| 11 | CLK |
| 12 | RESET |
| 13 | DACK2 |
| 14 | DACK3 |
| 15 | DRQ3 |
| 16 | DRQ2 |
| 17 | DRQ1 |
| 18 | DRQ0 |
| 19 | GND |
| 20 | GND |
| 21 | D7 |
| 22 | D6 |
| 23 | D5 |
| 24 | DACK1 |
| 25 | DACK0 |
| 26 | D4 |
| 27 | D3 |
| 28 | D2 |
| 29 | D1 |
| 30 | D0 |
| 31 | VCC |
| 32 | A0 |
| 33 | A1 |
| 34 | A2 |
| 35 | A3 |
| 36 | EOP |
| 37 | A4 |
| 38 | A5 |
| 39 | A6 |
| 40 | A7 |
Applications:
- Microprocessor systems.
- Industrial control equipment.
- Computer motherboards.
- Data acquisition systems.
- Embedded controllers.
- Communication equipment.
- Disk controllers.
- Network interface hardware.
- Memory management systems.
- Legacy computer repairs and restorations.
- Educational microprocessor projects.
- Peripheral interface systems.
Package Included:
- 1x D8237AC-5 Direct Memory Access (DMA) Controller.