Cypress manual CY7C145, CY7C144

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CY7C145, CY7C144

Switching Waveforms (continued)

 

 

 

Figure 8. Write Cycle No. 1: OE Three-State Data I/Os (Either Port)[21, 22, 23]

 

tWC

 

 

ADDRESS

 

 

 

SEM OR CE

tSCE

 

 

 

 

 

 

tAW

 

tHA

R/W

tPWE

 

 

 

 

 

 

tSA

tSD

tHD

DATA IN

 

DATA VALID

 

OE

 

 

 

 

tHZOE

 

tLZOE

DATA OUT

HIGH IMPEDANCE

 

 

 

 

 

Figure 9. Write Cycle No. 2: R/W Three-State Data I/Os (Either Port)[21, 23, 24]

 

tWC

 

 

ADDRESS

 

 

 

 

tSCE

 

tHA

SEM OR CE

 

 

 

 

tAW

t

 

 

tSA

 

R/W

 

PWE

 

 

 

 

 

 

tSD

tHD

DATA IN

 

DATAVALID

 

 

t

 

tLZWE

 

HZWE

 

 

DATA OUT

 

HIGH IMPEDANCE

 

 

 

Notes

21.The internal write time of the memory is defined by the overlap of CE or SEM LOW and R/W LOW. Both signals must be LOW to initiate a write, and either signal can terminate a write by going HIGH. The data input set-up and hold timing should be referenced to the rising edge of the signal that terminates the write.

22.If OE is LOW during a R/W controlled write cycle, the write pulse width must be the larger of tPWE or (tHZWE + tSD) to allow the I/O drivers to turn off and data to be placed on the bus for the required tSD. If OE is HIGH during a R/W controlled write cycle (as in this example), this requirement does not apply and the write pulse can be as short as the specified tPWE.

23.R/W must be HIGH during all address transitions.

24.Data I/O pins enter high impedance when OE is held LOW during write.

Document #: 38-06034 Rev. *D

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Contents Logic Block Diagram FeaturesFunctional Description Cypress Semiconductor Corporation 198 Champion CourtPin Plcc Top View Pin ConfigurationsPin Definitions Left Port Right Port Description Selection Guide DescriptionUnit Electrical Characteristics Over the Operating Range Maximum RatingsOperating Range Parameter Description Test Conditions Max Unit CapacitanceSwitching Characteristics Over the Operating Range9 7C144-15 Switching Characteristics Over the Operating Range7C144-35 7C144-55 Parameter Description 7C145-15 7C145-35 7C145-55 Unit MinRead Cycle No Either Port Address Access15 Switching WaveformsCY7C145, CY7C144 Semaphore Read After Write Timing, Either Side25 Read with Busy M/S=HIGH20 Right Address Valid First CER Valid FirstRight Side Clears INT R Left Side Sets INT RRight Side Sets INT L Left Side Clears IntlArchitecture Operation Non-Contending Read/Write Inputs OutputsInterrupt Operation Example assumes = High Function Left Port Right PortTypical DC and AC Characteristics 8K x8 Dual-Port Sram Ordering InformationPin Plastic Leaded Chip Carrier CY7C144-15JXC Pin Plastic Leaded Chip Carrier CY7C144-55JXCPin Plastic Leaded Chip Carrier CY7C145-35JXC 8K x9 Dual-Port SramPin Thin Plastic Quad Flat Pack 14 x 14 x 1.4 mm A65 Package DiagramsPin Thin Plastic Quad Flat Pack A80 Sales, Solutions and Legal Information Worldwide Sales and Design Support Products PSoC SolutionsDocument History

CY7C145, CY7C144 specifications

Cypress Semiconductor is renowned for its advanced memory solutions, and two of its noteworthy products are the CY7C144 and CY7C145, both of which serve as emerging leaders in the field of synchronous dynamic random-access memory (SDRAM). These memory chips provide high-speed data access, making them ideal for various applications, including networking, automotive, and industrial electronics.

The CY7C144 is a 4-Mbit SRAM, while its counterpart, the CY7C145, is an 8-Mbit SRAM. Both chips utilize a synchronous interface, which allows them to operate at clock rates that significantly enhance data retrieval speeds. Designed for low power consumption, these devices feature several power-saving modes, making them suitable for battery-operated applications.

One of the main features of the CY7C144 and CY7C145 is their support for burst read and write operations. This function enables the memory to deliver multiple bits of data sequentially with a single command, substantially increasing throughput. Additionally, both models come with a wide data bus, typically 16 bits, allowing for efficient data handling and alignment with a variety of systems.

The technology behind these chips includes static CMOS processes, which promote high performance and reliability under various operating environments. The CY7C144 and CY7C145 both guarantee a high level of data integrity, thanks to advanced error detection and correction features. This makes them especially valuable in applications where data accuracy is critical.

Another critical aspect is the integration of an on-chip address decoder for efficient memory addressing, minimizing delays during data access. This characteristic plays a crucial role in optimizing the overall system performance, particularly in high-bandwidth applications.

In terms of environmental resilience, these memories are designed to withstand a range of temperatures, making them robust enough for industrial applications. The CY7C144 and CY7C145 also comply with several industry standards, ensuring compatibility with a wide array of devices and systems.

In summary, the CY7C144 and CY7C145 by Cypress Semiconductor stand out due to their blend of high speed, low power consumption, and robust reliability. With advanced features like burst read/write capabilities, error detection, and temperature resilience, these memory chips are exceptional choices for modern electronic applications demanding speed and efficiency. Their continued evolution reflects Cypress's commitment to innovation in the semiconductor industry, catering to the growing needs of a data-driven world.
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