Cypress CY7C138, CY7C139 Right Side Clears INT R, Right Side Sets Intl, Left Side Clears Intl

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CY7C138, CY7C139

Switching Waveforms (continued)

Figure 14. Interrupt Timing Diagrams

Left Side Sets INTR:

ADDRESSL

CE L

R/W L

INTR

tWC

WRITE FFF

t [31]

tINS[32]

Right Side Clears INTR:	tRC
ADDRESSR	READ FFF
CE R
	tINR[32]
R/W R
OE R
INTR

Right Side Sets INTL:

	tWC
ADDRESSR	WRITE FFE
CER	tHA[31]
CER
R/W R
INT L
	tINS[32]

Left Side Clears INTL:

tRC

ADDRESSR

READ FFE

CE L

tINR[32]

R/W L

OE L

INT L

Notes

31.tHA depends on which enable pin (CEL or R/WL) is deasserted first.

32.tINS or tINR depends on which enable pin (CEL or R/WL) is asserted last.

Document #: 38-06037 Rev. *D

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Contents Features Logic Block DiagramFunctional Description Cypress Semiconductor Corporation 198 Champion CourtPin Configurations Pin Definitions Left Port Right Port DescriptionSelection Guide Description UnitElectrical Characteristics Over the Operating Range TemperatureMaximum Ratings Operating RangeCapacitance8 Parameter Description Test Conditions Max UnitSwitching Characteristics Over the Operating Range9 OutputGND ALL Input PulsesSwitching Waveforms TimingBusy Data OUTData OUT Data Valid Address R MatchData INR Valid Address L Match Data Outl ValidAddress SEM or CE Data Data ValidHigh Impedance AddressValid Address SEMDataout Valid Write Cycle Read CycleAddressr Match Data INR ValidAddressl Match BusylAddress L,R Address Match CEL CER Busyr ADDRESSL,R CER CEL Busy LAddress L Addressr Busyr Address Match Address MismatchRight Side Clears INT R Right Side Sets IntlLeft Side Clears Intl Architecture Write OperationNon-Contending Read/Write Inputs Outputs Operation Interrupt Operation Example assumesRight Port Function Supply Voltage Ambient Temperature C Output Voltage Normalized Supply CurrentOutput Source Current NormalizedPackage Diagram Ordering InformationSpeed Ordering Code Package Type OperatingSales, Solutions and Legal Information Document History

CY7C138, CY7C139 specifications

The Cypress CY7C139 and CY7C138 are advanced static random-access memory (SRAM) components that have garnered attention in the field of digital electronics due to their high performance and reliability. These SRAMs are designed to meet the demanding needs of a variety of applications, ranging from telecommunications to automotive systems and consumer electronics.

The CY7C139 is a 128K x 8 bit static RAM, while the CY7C138 is a 256K x 8 bit SRAM, offering flexible memory solutions for designers. Both devices utilize a fast access time, typically around 10 to 15 nanoseconds, allowing quick data retrieval essential for high-speed applications. This remarkable speed is complemented by low power consumption, making them suitable for battery-operated devices and other applications where efficiency is paramount.

One of the key features of the CY7C139 and CY7C138 is their asynchronous operation, which enables them to provide high-speed data access without the need for a clock signal. This characteristic simplifies system design and enhances performance, as users can write to and read from the memory without waiting for synchronization. The devices support standard CMOS interface levels, which facilitate integration into a diverse range of digital systems.

Additionally, these SRAMs have been designed with a low standby current, making them particularly effective for low-power applications. The devices also include a robust input/output structure that ensures reliable signal integrity under various operating conditions. Their built-in data retention capability allows the SRAMs to retain stored data even during power failures, a critical feature in many systems that require data preservation.

Both CY7C139 and CY7C138 SRAMs support a wide range of temperature and voltage ranges, making them suitable for industrial and automotive environments. They are packaged in industry-standard configurations, allowing for easy integration into existing designs.

In summary, the Cypress CY7C139 and CY7C138 SRAMs provide high-speed, low-power memory solutions suitable for various applications. Their asynchronous operation, low standby current, and robust performance characteristics make them a preferred choice for engineers looking to enhance system efficiency and reliability. These features make the CY7C139 and CY7C138 indispensable components in modern digital electronic designs.