PixArt Imaging Inc.
ADBS-A350 Optical Finger Navigation
4-wire Serial Peripheral Interface (SPI)
SPI Specifications
Electrical Characteristics over recommended operating conditions. Typical values at 25° C, VDD = 1.8 V.
Parameter
Symbol
Minimum Typical
Maximum Units Notes
Serial Port Clock
Frequency
fsclk
1
MHz Active drive, 50% duty cycle
MISO rise time
tr-MISO
150
150
300
300
120
ns
ns
ns
CL = 100 pF
CL = 100 pF
MISO fall time
tf-MISO
MISO delay after SCLK
tDLY_MISO
From SCLK falling edge to MISO data
valid, no load conditions
MISO hold time
MOSI hold time
thold_MISO
thold_MOSI
0.5
1/fSCLK
μs
ns
Data held until next falling SCLK edge
200
Amount of time data is valid after SCLK
rising edge
MOSI setup time
tsetup_MOSI
tSWW
120
30
ns
From data valid to SCLK rising edge
SPI time between write
commands
s
From rising SCLK for last bit of the first
data byte, to rising SCLK for last bit of the
second data byte.
SPI time between write
and read commands
tSWR
20
500
4
s
ns
s
From rising SCLK for last bit of the first
data byte, to rising SCLK for last bit of the
second address byte.
SPI time between read
and subsequent
commands
tSRW
tSRR
From rising SCLK for last bit of the first
data byte, to falling SCLK for the first bit of
the address byte of the next command.
SPI read address-data
delay
tSRAD
From rising SCLK for last bit of the address
byte, to falling SCLK for first bit of data
being read.
NCS inactive after
motion burst
tBEXIT
500
120
120
20
ns
ns
ns
us
ns
Minimum NCS inactive time after
motion burst before next SPI usage
NCS to SCLK active
tNCS-SCLK
tSCLK-NCS
tSCLK-NCS
tNCS-MISO
From NCS falling edge to first SCLK falling
edge
SCLK to NCS inactive
(for read operation)
From last SCLK rising edge to NCS
rising edge, for valid MISO data transfer
SCLK to NCS inactive
(for write operation)
From last SCLK rising edge to NCS
rising edge, for valid MOSI data transfer
NCS to MISO high-Z
500
From NCS rising edge to MISO high-Z
state
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PixArt Imaging Inc.
E-mail: fae_service@pixart.com.tw
15
PIXART [ PIXART IMAGING INC. ]
