EN25F40_1 Datasheet, PDF (4/35 Pages) Eon Silicon Solution Inc. – 4 Megabit Serial Flash Memory with 4Kbytes Uniform Sector

EN25F40
SIGNAL DESCRIPTION
Serial Data Input (DI)
The SPI Serial Data Input (DI) pin provides a means for instructions, addresses and data to be serially
written to (shifted into) the device. Data is latched on the rising edge of the Serial Clock (CLK) input pin.
Serial Data Output (DO)
The SPI Serial Data Output (DO) pin provides a means for data and status to be serially read from
(shifted out of) the device. Data is shifted out on the falling edge of the Serial Clock (CLK) input pin.
Serial Clock (CLK)
The SPI Serial Clock Input (CLK) pin provides the timing for serial input and output operations. ("See
SPI Mode")
Chip Select (CS#)
The SPI Chip Select (CS#) pin enables and disables device operation. When CS# is high the device is
deselected and the Serial Data Output (DO) pin is at high impedance. When deselected, the devices
power consumption will be at standby levels unless an internal erase, program or status register cycle is
in progress. When CS# is brought low the device will be selected, power consumption will increase to
active levels and instructions can be written to and data read from the device. After power-up, CS# must
transition from high to low before a new instruction will be accepted.
Hold (HOLD#)
The HOLD pin allows the device to be paused while it is actively selected. When HOLD is brought low,
while CS# is low, the DO pin will be at high impedance and signals on the DI and CLK pins will be
ignored (don’t care). The hold function can be useful when multiple devices are sharing the same SPI
signals.
Write Protect (WP#)
The Write Protect (WP#) pin can be used to prevent the Status Register from being written. Used in
conjunction with the Status Register’s Block Protect (BP0, BP1and BP2) bits and Status Register Protect
(SRP) bits, a portion or the entire memory array can be hardware protected.
Table 1. PIN Names
Symbol
CLK
DI
DO
CS#
WP#
HOLD#
Vcc
Vss
Pin Name
Serial Clock Input
Serial Data Input
Serial Data Output
Chip Enable
Write Protect
Hold Input
Supply Voltage (2.3-3.6V)
Ground
This Data Sheet may be revised by subsequent versions
4
or modifications due to changes in technical specifications.
©2004 Eon Silicon Solution, Inc.,
Rev. I, Issue Date: 2010/05/31
www.eonssi.com