SF600/SF600
Plus
Serial Flash Programming solution
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Remark: the total capacitance added on the application SPI bus will also depend on the
ICP cable length. The ICP cable length must be reduced at the minimum. The SPI flash
output buffer capability (MISO) is limited compared to the programmer performances.
So even if the programmer is able to drive high capacitance, the Serial Flash soldered
on the application will probably not (information read from SPI Flash will be wrong).
C. Smart management of the SPI Flash Vcc and SPI signals
In order to minimize the impact of the ICP method on the chipset and application
board, the programmer supplies the application Serial Flash with Vcc and SPI signals
only during the programmer and Serial Flash operations.
Advantages:
a) The programmer is plugged on the application board with Vcc OFF and SPI
signals in High Impedance to avoid inrush current.
b) All the ICP pins are protected with ESD high performance protections to
discharge the Electronics charge before the connection and protect the
application.
c) The Serial Flash Vcc and SPI signals are provided only when the user send the
command and are switched OFF automatically when the operation is completed.
Therefore, the programmer is transparent for the application and can be kept
connected during application trials.
D. High voltage supply: Vpp/Acc
Specification for the Vpp pin
Vpp = 5V to 12V
Ipp max = 70mA
The Vpp high voltage can be supplied by the programmer and used to speed up
programming and erasing of the application Serial Flash if this feature is supported
by the Serial Flash supplier.
The Vpp supply will be applied automatically by the programmer on the Vpp pin
only during erase, write, or programming operations and only if the Vpp option has
been enabled on the software. The programmer will also control the Vpp voltage
level according to the Serial Flash connected and its specification.
E. I/O management: IO1, IO2, Reset/IO3
Two general IO are available on the ICP connector and one Reset for custom
needs. The IOs and reset are in High Impedance (HZ) state if there is no software
operation ongoing.
Reset/IO3: The reset/IO3 pin is an open drain output which can be used to reset
the target system or turn off the isolation circuit.
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