Cypress CY62157EV18 Manual De Usuario

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Cypress Semiconductor Corporation
198 Champion Court
San Jose
,
CA 95134-1709
408-943-2600
Document #: 38-05490 Rev. *D
 Revised March 30, 2007
CY62157EV18 MoBL
®
8-Mbit (512K x 16) Static RAM
Features
• Very high speed: 55 ns
• Wide voltage range: 1.65V–2.25V
• Pin Compatible with CY62157DV18 and CY62157DV20
• Ultra low standby power
— Typical Standby current: 2 
µA
— Maximum Standby current: 8 
µA
• Ultra low active power
—  Typical active current: 1.8 mA @ f = 1 MHz
• Easy memory expansion with CE
1
, CE
2
 and OE features
• Automatic power down when deselected
• CMOS for optimum speed and power
• Available in Pb-free 48-ball VFBGA package
Functional Description 
The CY62157EV18 is a high performance CMOS static RAM
organized as 512K words by 16 bits. This device features
advanced circuit design to provide ultra low active current.
This is ideal for providing More Battery Life™ (MoBL
®
) in
portable applications such as cellular telephones. The device
also has an automatic power down feature that significantly
reduces power consumption when addresses are not toggling.
The device can also be put into standby mode when
deselected (CE
1
 HIGH or CE
LOW or both BHE and BLE are
HIGH). The input and output pins (IO
0
 through IO
15
) are
placed in a high impedance state when:
• Deselected (CE
HIGH or CE
2
 LOW)
• Outputs are disabled (OE HIGH)
• Both Byte High Enable and Byte Low Enable are disabled 
(BHE, BLE HIGH) or
• Write operation is active (CE
1
 LOW, CE
2
 HIGH and WE 
LOW).
Write to the device by taking Chip Enables (CE
LOW and CE
2
HIGH) and Write Enable (WE) input LOW. If Byte Low Enable
(BLE) is LOW, then data from IO pins (IO
0
 through IO
7
), is
written into the location specified on the address pins (A
0
through A
18
). If Byte High Enable (BHE) is LOW, then data
from IO pins (IO
8
 through IO
15
) is written into the location
specified on the address pins (A
0
 through A
18
).
Read from the device by taking Chip Enables (CE
LOW and
CE
2
 HIGH) and Output Enable (OE) LOW while forcing the
Write Enable (WE) HIGH. If Byte Low Enable (BLE) is LOW,
then data from the memory location specified by the address
pins appear on IO
0
 to IO
7
. If Byte High Enable (BHE) is LOW,
then data from memory appears on IO
8
 to IO
15
 for a complete description of read and write
modes.
Product Portfolio 
Product
V
CC
 Range (V)
Speed 
(ns)
Power Dissipation
Operating I
CC
, (mA)
Standby, I
SB2
 (
µA)
f = 1MHz
f = f
max
Min
Typ 
Max
Typ 
[2]
Max
Typ 
Max
Typ 
Max
CY62157EV18
1.65
1.8
2.25
55
1.8
3
18
25
2
8
Notes
1. For best practice recommendations, refer to the Cypress application note “System Design Guidelines” located at 
http://www.cypress.com.
2. Typical values are included for reference only and are not guaranteed or tested. Typical values are measured at V
CC
 = V
CC(typ)
, T
A
 = 25°C.