CY7C1411JV18, CY7C1426JV18 CY7C1413JV18, CY7C1415JV18

IDCODE

The IDCODE instruction loads a vendor-specific, 32-bit code into the instruction register. It also places the instruction register between the TDI and TDO pins and shifts the IDCODE out of the device when the TAP controller enters the Shift-DR state. The IDCODE instruction is loaded into the instruction register at power up or whenever the TAP controller is given a Test-Logic-Reset state.

SAMPLE Z

The SAMPLE Z instruction connects the boundary scan register between the TDI and TDO pins when the TAP controller is in a Shift-DR state. The SAMPLE Z command puts the output bus into a High-Z state until the next command is given during the Update IR state.

SAMPLE/PRELOAD

SAMPLE/PRELOAD is a 1149.1 mandatory instruction. When the SAMPLE/PRELOAD instructions are loaded into the instruction register and the TAP controller is in the Capture-DR state, a snapshot of data on the input and output pins is captured in the boundary scan register.

The user must be aware that the TAP controller clock can only operate at a frequency up to 20 MHz, while the SRAM clock operates more than an order of magnitude faster. Because there is a large difference in the clock frequencies, it is possible that during the Capture-DR state, an input or output undergoes a transition. The TAP may then try to capture a signal while in transition (metastable state). This does not harm the device, but there is no guarantee as to the value that is captured. Repeatable results may not be possible.

To guarantee that the boundary scan register captures the correct value of a signal, the SRAM signal must be stabilized long enough to meet the TAP controller's capture setup plus hold times (tCS and tCH). The SRAM clock input might not be captured correctly if there is no way in a design to stop (or slow) the clock during a SAMPLE/PRELOAD instruction. If this is an issue, it is still possible to capture all other signals and simply ignore the value of the CK and CK captured in the boundary scan register.

After the data is captured, it is possible to shift out the data by putting the TAP into the Shift-DR state. This places the boundary scan register between the TDI and TDO pins.

PRELOAD places an initial data pattern at the latched parallel outputs of the boundary scan register cells before the selection of another boundary scan test operation.

The shifting of data for the SAMPLE and PRELOAD phases can occur concurrently when required, that is, while the data captured is shifted out, the preloaded data can be shifted in.

BYPASS

When the BYPASS instruction is loaded in the instruction register and the TAP is placed in a Shift-DR state, the bypass register is placed between the TDI and TDO pins. The advantage of the BYPASS instruction is that it shortens the boundary scan path when multiple devices are connected together on a board.

EXTEST

The EXTEST instruction drives the preloaded data out through the system output pins. This instruction also connects the boundary scan register for serial access between the TDI and TDO in the Shift-DR controller state.

EXTEST OUTPUT BUS TRI-STATE

IEEE Standard 1149.1 mandates that the TAP controller be able to put the output bus into a tri-state mode.

The boundary scan register has a special bit located at bit #108. When this scan cell, called the “extest output bus tri-state,” is latched into the preload register during the Update-DR state in the TAP controller, it directly controls the state of the output (Q-bus) pins, when the EXTEST is entered as the current instruction. When HIGH, it enables the output buffers to drive the output bus. When LOW, this bit places the output bus into a High-Z condition.

This bit can be set by entering the SAMPLE/PRELOAD or EXTEST command, and then shifting the desired bit into that cell, during the Shift-DR state. During Update-DR, the value loaded into that shift-register cell latches into the preload register. When the EXTEST instruction is entered, this bit directly controls the output Q-bus pins. Note that this bit is preset HIGH to enable the output when the device is powered up, and also when the TAP controller is in the Test-Logic-Reset state.

Reserved

These instructions are not implemented but are reserved for future use. Do not use these instructions.

Document Number: 001-12557 Rev. *C

Page 13 of 28

[+] Feedback

Page 13
Image 13
Cypress CY7C1411JV18, CY7C1426JV18, CY7C1415JV18, CY7C1413JV18 manual Idcode

CY7C1413JV18, CY7C1426JV18, CY7C1411JV18, CY7C1415JV18 specifications

Cypress Semiconductor, known for its innovative memory solutions, offers a range of high-performance SRAM products suitable for a variety of applications. Among these are the CY7C1415JV18, CY7C1411JV18, CY7C1426JV18, and CY7C1413JV18, which feature advanced technologies and robust performance characteristics.

The CY7C1415JV18 is a 4-Mbit high-speed asynchronous SRAM. Designed for applications requiring fast data access, it boasts a maximum access time of just 10 ns. This product operates at a supply voltage of 1.8V, making it ideal for low-power systems. It supports a simple interface, allowing for easy integration into various digital systems. Enhanced data integrity is assured through support for write cycles and concurrent read operations, making it suitable for high-demand environments.

The CY7C1411JV18 is a 2-Mbit synchronous SRAM that offers high speed and low latency. Its access time is optimized for high-performance applications, reaching speeds of up to 10 ns as well. The device is designed with a flexible interface that accommodates both burst and non-burst operations, increasing data throughput for memory-intensive tasks. Like its counterparts, it operates on a low voltage, ensuring minimal power consumption.

Next, the CY7C1426JV18 also belongs to Cypress's high-performance SRAM family, providing 2-Mbit storage capacity with excellent read and write performance characteristics. This SRAM features an advanced design that supports pipelined operations, allowing multiple memory accesses to occur simultaneously. This feature effectively maximizes data transmission rates, making it particularly appealing for applications needing rapid data processing.

Finally, the CY7C1413JV18 offers 1-Mbit of SRAM capacity optimized for speed and efficiency. With an access time of 9 ns, it is among the fastest products in its category. The device features advanced functionalities enabling compatibility with various hardware configurations, thus facilitating its use in a wide array of embedded systems.

All these SRAM devices feature low power consumption, making them suitable for battery-operated devices and energy-efficient applications. Their ability to operate at lower voltages while maintaining high performance is a key characteristic that aligns with modern design requirements. The combination of speed, low power, and flexibility makes the CY7C1415JV18, CY7C1411JV18, CY7C1426JV18, and CY7C1413JV18 highly sought after in industries ranging from telecommunications to consumer electronics, solidifying Cypress's reputation as a leader in memory solutions.