FM25V01A Datasheet, PDF (3/22 Pages) Cypress Semiconductor – 128-Kbit (16K × 8) Serial (SPI) F-RAM

FM25V01A
Pinout
Figure 1. 8-pin SOIC Pinout
CS 1
8
SO 2 Top View 7
not to scale
WP ³
6
V_SS 4
5
VDD
HOLD
SCK
SI
Pin Definitions
Pin Name
SCK
I/O Type
Input
Description
Serial Clock. All I/O activity is synchronized to the serial clock. Inputs are latched on the rising edge
and outputs occur on the falling edge. Because the device is synchronous, the clock frequency may
be any value between 0 and 40 MHz and may be interrupted at any time.
CS
SI^[1]
SO^[1]
WP
HOLD
V_SS
V_DD
Input
Chip Select. This active LOW input activates the device. When HIGH, the device enters low-power
standby mode, ignores other inputs, and the output is tristated. When LOW, the device internally
activates the SCK signal. A falling edge on CS must occur before every opcode.
Input
Serial Input. All data is input to the device on this pin. The pin is sampled on the rising edge of SCK
and is ignored at other times. It should always be driven to a valid logic level to meet I_DD specifica-
tions.
Output
Serial Output. This is the data output pin. It is driven during a read and remains tristated at all other
times including when HOLD is LOW. Data transitions are driven on the falling edge of the serial clock.
Input
Write Protect. This active LOW pin prevents write operation to the Status Register when WPEN is
set to ‘1’. This is critical because other write protection features are controlled through the Status
Register. A complete explanation of write protection is provided on Status Register and Write
Protection on page 7. This pin must be tied to V_DD if not used.
Input
HOLD Pin. The HOLD pin is used when the host CPU must interrupt a memory operation for another
task. When HOLD is LOW, the current operation is suspended. The device ignores any transition
on SCK or CS. All transitions on HOLD must occur while SCK is LOW. This pin has a weak internal
pull-up (refer to the R_IN spec in DC Electrical Characteristics).
Power supply Ground for the device. Must be connected to the ground of the system.
Power supply Power supply input to the device.
Note
1. SI may be connected to SO for a single pin data interface.
Document Number: 001-90881 Rev. *E
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