Non Volatile RAM
Manufactured in the UK
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Manufactured in the UK
NVRAM is ‘Non-Volatile Random Access Memory.’ It is a type of Random Access Memory that retains data after the host device’s power is turned off or has suffered an inadvertent power loss.
The Greenwich Instruments NVRAM devices retain critical data, at this point of power failure, by using an alternative source of power in the form of its self-contained, internal, lithium battery. This Non-volatile Static RAM is often used to store computer hardware settings or data that needs to be maintained when the computer is shut down.
Power down is very fast, essential for data integrity. The power down circuit is referenced and triggered at 4.5V. Data is retained in less than 15microseconds, much faster than power failure conditions.
Greenwich Instruments NVRAM is manufactured in JEDEC standard DIL (Dual In-Line) packages.
The 16k GR281 is in a 24pin dil package, the 64k GR881 and the 256k GR3281 are in 28pin dil packages
The 1M GR12883 (in a 32pin dil package) is no longer manufactured
When powered down, these devices are transportable and data can be moved from system to system. They are pin-compatible with standard EPROMS, ideal for program development, data collection in dataloggers, program changes in process control, robotics and user-defined lookup tables.
The GR281 is a 2048 word by 8 bits (2k x 8) non-volatile static RAM fabricated from advanced silicon gate CMOS technology and a high reliability lithium power cell.
The 24W dil pinout of the GR281 conforms to the JEDEC standards and is fully compatible with normal static RAM
The GR881 is a 8192 word by 8 bits (8k x 8) non-volatile static RAM fabricated from advanced silicon gate CMOS technology and a high reliability lithium power cell.
The 28W dil pinout of the GR881 conforms to the JEDEC standards and is fully compatible with normal static RAM
The GR3281 is a 32768 word by 8 bits (32k x 8) non-volatile static RAM fabricated from advanced silicon gate CMOS technology and a high reliability lithium power cell.
The 28W dil pinout of the GR3281 conforms to the JEDEC standards and is fully compatible with normal static RAM
Manufactured in the UK
The GSM2 is a standalone drive board designed to drive a stepper motor in unipolar mode. It is done either with or without forcing resistors connected between motor commons and supply voltage.
When using the logic connections, you are able to select full, half or wave mode and direction and speed external clock. The GSM2 drive board allows an enable and disable input for various start/stop control options. The stepper motor used with the board must also have four phases and five, six or eight wires.
Compatible with any four phase unipolar stepper motors up to 2A/40Vdc per phase with full, half and wave modes able to be selected.
* field input required