74LS170 is a high-speed, low-power 4 x 4 Register File organized as four words by four bits. Separate read and write inputs, both address and enable, allow simultaneous read and write operation. Open-collector outputs make it possible to connect up to 128 outputs in a wired-AND configuration to increase the word capacity up to 512 words. The output of this IC always comes in TTL which makes it easy to work with other TTL devices and microcontrollers. The IC 74LS170 is smaller in size and it has a much faster speed which makes it reliable in every kind of device.
What is a 4×4 Register File?
A register file is an array of processor registers in a central processing unit (CPU) of any computing system. The register file is the component that contains all the general purpose registers of the microprocessor. Register files make it possible to simultaneously read from any number of registers with in a computing system and write into one register as appropriate for the processor.
74LS170 Key Features & Specifications
- Technology Family: LS
- Rating: Catalog
- Supply voltage: 5.25V
- Frequency at nominal voltage: 35 MHz
- Typical propagation delay: 21ns
- Simultaneous Read/Write Operation
- Expandable to 512 Words of n-Bits
- Typical Access Time of 20 ns
- Low Leakage Open-Collector Outputs for Expansion
- Typical Power Dissipation of 125 mW
- ESD protection
- Operating temperature: 0ºC to 70ºC
74LS170 Pinout
| Pin No. | Pin Name | Description |
|---|---|---|
| 1 | D2 | Data Input 2 |
| 2 | D3 | Data Input 3 |
| 3 | D4 | Data Input 4 |
| 4 | RB | Read Address Input B |
| 5 | RA | Read Address Input A |
| 6 | Q4 | Output Pin 4 |
| 7 | Q3 | Output Pin 3 |
| 8 | GND | Ground |
| 9 | Q2 | Output Pin 2 |
| 10 | Q1 | Output Pin 1 |
| 11 | ER‘ | Active low Read Enable Input |
| 12 | EW‘ | Active low write Enable input |
| 13 | WB | Write Address Input B |
| 14 | WA | Write Address Input A |
| 15 | D1 | Data Input 1 |
| 16 | VCC | Chip Supply Voltage |
Applications
- Random access register files are suitable for scratch-pad memories. This function is useful for communication between different controllers or processors or as a temporary fast storage.
74LS170 Datasheet
You can download the 74LS170 4×4 Register File Open-Collector IC Datasheet from the link given below:
See Also: 74LS164 8-Bit Shift Register IC With Parallel Outputs – Datasheet | 74LS148 8 To 3 Line Priority Encoder IC – Datasheet | 74LS124 Dual Voltage Controlled Oscillator IC – Datasheet
