Cypress CY7C1529AV18, CY7C1524AV18, CY7C1522AV18 manual Ieee 1149.1 Serial Boundary Scan Jtag

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CY7C1522AV18, CY7C1529AV18 CY7C1523AV18, CY7C1524AV18

IEEE 1149.1 Serial Boundary Scan (JTAG)

These SRAMs incorporate a serial boundary scan Test Access Port (TAP) in the FBGA package. This part is fully compliant with IEEE Standard #1149.1-2001. The TAP operates using JEDEC standard 1.8V IO logic levels.

Disabling the JTAG Feature

It is possible to operate the SRAM without using the JTAG feature. To disable the TAP controller, TCK must be tied LOW (VSS) to prevent clocking of the device. TDI and TMS are inter- nally pulled up and may be unconnected. They may alternatively be connected to VDD through a pull up resistor. TDO must be left unconnected. Upon power up, the device comes up in a reset state, which does not interfere with the operation of the device.

Test Access Port—Test Clock

The test clock is used only with the TAP controller. All inputs are captured on the rising edge of TCK. All outputs are driven from the falling edge of TCK.

Test Mode Select (TMS)

The TMS input is used to give commands to the TAP controller and is sampled on the rising edge of TCK. This pin may be left unconnected if the TAP is not used. The pin is pulled up inter- nally, resulting in a logic HIGH level.

Test Data-In (TDI)

The TDI pin is used to serially input information into the registers and can be connected to the input of any of the registers. The register between TDI and TDO is chosen by the instruction that is loaded into the TAP instruction register. For information on loading the instruction register, see the TAP Controller State Diagram on page 14. TDI is internally pulled up and can be unconnected if the TAP is unused in an application. TDI is connected to the most significant bit (MSB) on any register.

Test Data-Out (TDO)

The TDO output pin is used to serially clock data out from the registers. The output is active, depending upon the current state of the TAP state machine (see Instruction Codes on page 17). The output changes on the falling edge of TCK. TDO is connected to the least significant bit (LSB) of any register.

Performing a TAP Reset

A Reset is performed by forcing TMS HIGH (VDD) for five rising edges of TCK. This Reset does not affect the operation of the SRAM and can be performed while the SRAM is operating. At power up, the TAP is reset internally to ensure that TDO comes up in a high-Z state.

TAP Registers

Registers are connected between the TDI and TDO pins to scan the data in and out of the SRAM test circuitry. Only one register can be selected at a time through the instruction registers. Data is serially loaded into the TDI pin on the rising edge of TCK. Data is output on the TDO pin on the falling edge of TCK.

Instruction Register

Three-bit instructions can be serially loaded into the instruction register. This register is loaded when it is placed between the TDI and TDO pins, as shown in TAP Controller Block Diagram on page 15. Upon power up, the instruction register is loaded with the IDCODE instruction. It is also loaded with the IDCODE instruction if the controller is placed in a reset state, as described in the previous section.

When the TAP controller is in the Capture-IR state, the two least significant bits are loaded with a binary “01” pattern to allow for fault isolation of the board level serial test path.

Bypass Register

To save time when serially shifting data through registers, it is sometimes advantageous to skip certain chips. The bypass register is a single-bit register that can be placed between TDI and TDO pins. This enables shifting of data through the SRAM with minimal delay. The bypass register is set LOW (VSS) when the BYPASS instruction is executed.

Boundary Scan Register

The boundary scan register is connected to all of the input and output pins on the SRAM. Several No Connect (NC) pins are also included in the scan register to reserve pins for higher density devices.

The boundary scan register is loaded with the contents of the RAM input and output ring when the TAP controller is in the Capture-DR state and is then placed between the TDI and TDO pins when the controller is moved to the Shift-DR state. The EXTEST, SAMPLE/PRELOAD, and SAMPLE Z instructions can be used to capture the contents of the input and output ring.

The Boundary Scan Order on page 18 shows the order in which the bits are connected. Each bit corresponds to one of the bumps on the SRAM package. The MSB of the register is connected to TDI, and the LSB is connected to TDO.

Identification (ID) Register

The ID register is loaded with a vendor-specific, 32-bit code during the Capture-DR state when the IDCODE command is loaded in the instruction register. The IDCODE is hardwired into the SRAM and can be shifted out when the TAP controller is in the Shift-DR state. The ID register has a vendor code and other information described in Identification Register Definitions on page 17.

TAP Instruction Set

Eight different instructions are possible with the three-bit instruction register. All combinations are listed in Instruction Codes on page 17. Three of these instructions are listed as RESERVED and must not be used. The other five instructions are described in this section in detail.

Instructions are loaded into the TAP controller during the Shift-IR state when the instruction register is placed between TDI and TDO. During this state, instructions are shifted through the instruction register through the TDI and TDO pins. To execute the instruction after it is shifted in, the TAP controller must be moved into the Update-IR state.

Document #: 001-06981 Rev. *D

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Contents Features ConfigurationsFunctional Description Selection GuideLogic Block Diagram CY7C1522AV18 DoffCLK Logic Block Diagram CY7C1523AV18 Logic Block Diagram CY7C1524AV18Pin Configuration Ball Fbga 15 x 17 x 1.4 mm PinoutCY7C1522AV18 8M x CY7C1529AV18 8M xCY7C1523AV18 4M x CY7C1524AV18 2M xPin Definitions Pin Name Pin DescriptionSynchronous Read/Write Input. When Power Supply Inputs to the Core of the Device Power Supply Inputs for the Outputs of the DeviceReferenced with Respect to TDO for JtagFunctional Overview Application Example Application ExampleTruth Table Write Cycle DescriptionsLD R/W BWS0/ BWS1 NWS0 NWS1BWS0 BWS0 BWS1 BWS2 BWS3Ieee 1149.1 Serial Boundary Scan Jtag Idcode TAP Controller State Diagram TAP Controller Block Diagram TAP Electrical CharacteristicsTDI TCKTAP AC Switching Characteristics TAP Timing and Test ConditionsIdentification Register Definitions Scan Register SizesInstruction Codes Register Name Bit SizeBoundary Scan Order Bit # Bump IDPower Up Sequence in DDR-II Sram Power Up SequenceDLL Constraints Electrical Characteristics DC Electrical CharacteristicsMaximum Ratings AC Electrical Characteristics Capacitance Thermal ResistanceParameter Description Test Conditions Max Unit Parameter Description Test Conditions Fbga UnitSwitching Characteristics HighLOW Static to DLL Reset DLL TimingSwitching Waveforms NOP Read WriteBurst Ordering Information 250 167 Package Diagram Ball Fbga 15 x 17 x 1.4 mmSales, Solutions, and Legal Information Worldwide Sales and Design Support Products PSoC SolutionsDocument History REV ECN no Submission ORIG. Description of Change Date

CY7C1529AV18, CY7C1523AV18, CY7C1524AV18, CY7C1522AV18 specifications

Cypress Semiconductor has established itself as a prominent player in the memory solutions market, and its family of high-performance synchronous static random-access memory (SRAM) devices has garnered significant attention. Among these, the CY7C1522AV18, CY7C1524AV18, CY7C1523AV18, and CY7C1529AV18 stand out due to their advanced features and reliable performance.

The CY7C1522AV18 is a 2 Megabit SRAM device designed to deliver fast access times with a dual-port architecture. This memory solution supports a 3.0V to 3.6V power supply range. With a high-speed operation of up to 167 MHz, it is ideal for applications that require rapid data processing and retrieval. Its unique architecture allows simultaneous read and write operations, which enhances throughput and efficiency in data handling.

Conversely, the CY7C1524AV18 is a 4 Megabit SRAM that builds upon these capabilities, offering an even larger storage option while maintaining similar speed and voltage specifications. Both devices come with Cyclical Redundancy Check (CRC) for data integrity, ensuring reliability in mission-critical applications. Additionally, these SRAMs feature a simple asynchronous interface, making integration into existing systems remarkably straightforward.

The CY7C1523AV18 offers a balance of features with its 3 Megabit capacity. Similar to its counterparts, this device also presents dual-port capabilities, which facilitate quick data access without bottlenecks, proving advantageous in high-performance computing environments.

Lastly, the CY7C1529AV18 rounds out the family with its impressive 9 Megabit capacity, providing ample memory for more extensive applications. Its enhanced architecture makes it suitable for advanced embedded systems where speed and reliability are paramount.

All four devices leverage Cypress’s innovative Synchronous SRAM technology, which offers low latency and high bandwidth, making them suited for high-performance applications such as networking, telecommunications, and industrial control systems. The memory chips are built with robust features including low power consumption modes and wide operating temperature ranges, enhancing their versatility in various environments.

In conclusion, the CYPRESS CY7C1522AV18, CY7C1524AV18, CY7C1523AV18, and CY7C1529AV18 are exemplary SRAM solutions that combine speed, capacity, and reliability, catering to a broad spectrum of contemporary electronic systems. Whether for embedded applications or high-speed network devices, these memory solutions continue to be at the forefront of technology advancements.
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