Cypress STK16C88 Hardware Protect, Noise Considerations, Low Average Active Power, Best Practices

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STK16C88

Hardware Protect

Figure 3. Current Versus Cycle Time (WRITE)

The STK16C88 offers hardware protection against inadvertent STORE operation and SRAM WRITEs during low voltage conditions. When VCAP<VSWITCH, all externally initiated STORE operations and SRAM WRITEs are inhibited.

Noise Considerations

The STK16C88 is a high speed memory. It must have a high frequency bypass capacitor of approximately 0.1 µF connected between VCC and VSS, using leads and traces that are as short as possible. As with all high speed CMOS ICs, careful routing of power, ground, and signals reduce circuit noise.

Low Average Active Power

CMOS technology provides the STK16C88 the benefit of drawing significantly less current when it is cycled at times longer than 50 ns. Figure 2 and Figure 3 shows the relationship between ICC and READ or WRITE cycle time. Worst case current consumption is shown for both CMOS and TTL input levels (commercial temperature range, VCC = 5.5V, 100% duty cycle on chip enable). Only standby current is drawn when the chip is disabled. The overall average current drawn by the STK16C88 depends on the following items:

1.The duty cycle of chip enable

2.The overall cycle rate for accesses

3.The ratio of READs to WRITEs

4.CMOS versus TTL input levels

5.The operating temperature

6.The VCC level

7.IO loading

Figure 2. Current Versus Cycle Time (READ)

Best Practices

nvSRAM products have been used effectively for over 15 years. While ease-of-use is one of the product’s main system values, experience gained working with hundreds of applica- tions has resulted in the following suggestions as best practices:

■The nonvolatile cells in an nvSRAM are programmed on the test floor during final test and quality assurance. Incoming inspection routines at customer or contract manufacturer’s sites, sometimes, reprogram these values. Final NV patterns are typically repeating patterns of AA, 55, 00, FF, A5, or 5A. End product’s firmware should not assume an NV array is in a set programmed state. Routines that check memory content values to determine first time system configuration and cold or warm boot status should always program a unique NV pattern (for example, complex 4-byte pattern of 46 E6 49 53 hex or more random bytes) as part of the final system manufacturing test to ensure these system routines work consistently.

■Power up boot firmware routines should rewrite the nvSRAM into the desired state. While the nvSRAM is shipped in a preset state, best practice is to again rewrite the nvSRAM into the desired state as a safeguard against events that might flip the bit inadvertently (program bugs or incoming inspection routines).

Document Number: 001-50595 Rev. **

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Contents Features Logic Block DiagramFunctional Description Cypress Semiconductor Corporation 198 Champion CourtPin Configurations Write Enable Input, Active LOW. When the chip is enabledOutput Enable, Active LOW. The active LOW Power Supply Inputs to the DeviceHardware Recall Power Up Device OperationSram Read Sram WriteLow Average Active Power Hardware ProtectNoise Considerations Best PracticesSoftware STORE/RECALL Mode Selection 13 a 0x0E38 Read Sram Output DataRead Sram Output Data 0x03E0 Read Sram Output Data 0x303FDC Electrical Characteristics Maximum RatingsOperating Range Data Retention and EnduranceCapacitance AC Test ConditionsDescription Test Conditions Max Unit Parameter Description Test Conditions Pdip UnitAC Switching Characteristics Switching WaveformsSwitching Min Max ParameterAutoStore or Power Up Recall Power up Recall DurationLow Voltage Reset Level Parameter Alt Description STK16C88 Unit Min MaxSoftware Controlled STORE/RECALL Cycle Parameter Alt Description 25 ns 45 ns Unit Min MaxOrdering Information Package Diagrams Pin 600 Mil PdipNew data sheet Sales, Solutions and Legal InformationDocument History

STK16C88 specifications

The Cypress STK16C88 is a highly regarded SRAM (Static Random Access Memory) device that is designed for high-performance computing applications. As a member of the Cypress family of memory solutions, the STK16C88 is known for its efficiency, speed, and reliability, making it a popular choice among engineers and developers seeking robust memory solutions for their projects.

One of the key features of the STK16C88 is its high-speed access capability. It operates at a maximum access time of just 55 nanoseconds, enabling rapid data retrieval and processing. This characteristic makes it particularly suitable for applications requiring quick response times, such as telecommunications, networking equipment, and industrial automation systems.

The STK16C88 boasts a dual-port architecture, which allows simultaneous access to data from multiple devices. This enhances the flexibility of the memory chip, making it ideal for multi-processor systems where efficient data sharing is critical. The dual-port feature also facilitates easier designs for applications that require real-time data processing and eliminates potential bottlenecks that might hinder system performance.

In terms of capacity, the STK16C88 provides 128K bits of memory, organized as 16K x 8 bits. This allocation of memory provides ample space for storing data and program code, making it versatile for various applications, including embedded systems and consumer electronics. Additionally, it supports asynchronous read/write operations, ensuring that the system can perform tasks without being held up by the memory component.

Another important characteristic of the STK16C88 is its low power consumption, which is vital for battery-operated devices and portable electronics. The device operates with a supply voltage of 3.3V, making it suitable for modern low-power applications. Its energy-efficient design extends battery life and reduces heat generation, further enhancing the reliability of the systems that utilize it.

Moreover, the STK16C88 is characterized by its compatibility with various industry-standard memory interfaces, allowing for seamless integration into existing systems. The simplicity of implementation, combined with its robust performance and reliability, makes it an excellent choice for manufacturers looking to enhance the capabilities of their devices.

In conclusion, the Cypress STK16C88 is a high-performance, low-power SRAM solution that is well-suited for various applications ranging from telecommunications to consumer electronics. Its key features, including dual-port architecture, high-speed access, and low power consumption, position it as a valuable component in the design of contemporary electronic systems.
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