Cypress CY7B991, CY7B992 manual Board-to-Board Clock Distribution

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CY7B991

CY7B992

		Figure 8. Board-to-Board Clock Distribution
			REF			LOAD
			REF
					Z0
			L1
	FB					LOAD
SYSTEM	REF					LOAD
SYSTEM	REF
CLOCK	FS		L2		Z0
	FS	4Q0	L2		Z0
	4F0	4Q0
	4F1	4Q1
	4F1
	3F0	3Q0
	3F1	3Q1	L3			LOAD
	2F0	2Q0			Z0
	2F1	2Q1			Z0
	2F1	2Q1
	1F0	1Q0	L4
	1F1	1Q1		FB
	TEST			FB
	TEST			REF
				REF
				FS	4Q0	LOAD
			Z0	4F0	4Q0
				4F0	4Q1
				4F1	4Q1
				3F0	3Q0
				3F1	3Q1
				2F0	2Q0	LOAD
				2F1	2Q1	LOAD
				1F0	1Q0
				1F1	1Q1
				TEST

Figure 8 shows the CY7B991 and 992 connected in series to construct a zero skew clock distribution tree between boards. Delays of the downstream clock buffers are programmed to compensate for the wire length (that is, select negative skew equal to the wire delay) necessary to connect them to the master clock source, approximating a zero delay clock tree. Cascaded clock buffers accumu- lates low frequency jitter because of the non-ideal filtering characteristics of the PLL filter. Do not connect more than two clock buffers in series.

Document Number: 38-07138 Rev. *B

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Contents Cypress Semiconductor Corporation 198 Champion Court FeaturesLogic Block Diagram Functional DescriptionPin Configuration Signal Name DescriptionPin Definitions Block Diagram Description Typical Outputs with FB Connected to a Zero-Skew Output Test ModeMaximum Ratings Operating RangeAmbient Range Electrical Characteristics Input Capacitance = 25 C, f = 1 MHz, V CC = CapacitanceAC Test Loads and Waveforms Parameter Description Test ConditionsParameter Description Min Typ Max Unit Switching Characteristics Over the Operating Range2Zero Output Skew All Outputs 16 Propagation Delay, REF Rise to FB RiseOver the Operating Range2 CY7B991-5 CY7B992-5 Parameter Description Unit Min Typ Max+1.5 Switching CharacteristicsCY7B991-7 CY7B992-7 Parameter Description Unit Min Typ Max +0.7AC Timing Diagrams Programmable Skew Clock Driver Operational Mode DescriptionsInverted Output Connections Multi-Function Clock Driver Board-to-Board Clock Distribution Ordering Information Accuracy Ordering Code Package Type Operating RangePb-Free Subgroups Military SpecificationsDC Characteristics Package DiagramsPin Rectangular Leadless Chip Carrier Document History Issue Date Orig. Description of Change

CY7B991, CY7B992 specifications

The Cypress CY7B992 and CY7B991 are advanced synchronous SRAM devices designed for high-speed applications, particularly in the field of telecommunications, networking, and high-performance computing. These SRAMs are notable for their ability to operate at high frequencies, making them suitable for systems that require rapid data access and processing.

One of the main features of the CY7B992 and CY7B991 is their support for synchronous operation, which allows for data transfers aligned with a clock signal. This capability significantly enhances performance by reducing access times and increasing data throughput compared to traditional asynchronous SRAMs. With their optimized write and read cycles, these devices can achieve low latency, enabling efficient data handling in real-time applications.

Another key technology utilized in these devices is the use of a 2-port architecture, which supports simultaneous read and write operations. This dual-port design allows for greater flexibility and efficiency in data management, making it easier to implement complex memory architectures in various applications. The architecture also supports burst mode operation, allowing for rapid sequential data access, which is crucial in environments where speed is paramount.

The CY7B992 and CY7B991 feature a wide data bus width, accommodating 32 bits to suit modern data processing needs. Their compact size and ease of integration into existing systems make them popular choices among designers and engineers. Moreover, these SRAMs offer a comprehensive range of voltage and temperature specifications, ensuring reliable performance across diverse operating conditions.

In terms of power management, the CY7B992 and CY7B991 are designed to consume low power while maintaining high performance, making them ideal for battery-operated or energy-sensitive applications. The devices include various power-saving features, such as power-down modes, enabling users to reduce overall system power consumption when the memory is not actively in use.

Overall, the Cypress CY7B992 and CY7B991 are robust, high-speed SRAM solutions that cater to the demands of sophisticated, data-intensive applications. Their synchronous operation, dual-port architecture, and efficient power management characteristics make them essential components in modern electronic systems. As technology continues to evolve, these SRAMs are poised to play a critical role in advancing the capabilities of next-generation devices.

Figure 8. Board-to-Board Clock Distribution

Document Number: 38-07138 Rev. *B

CY7B991, CY7B992 specifications