CYIL1SM1300AA_09 CYPRESS [Cypress Semiconductor], CYIL1SM1300AA_09 Datasheet - Page 8

• Manufacturer Part Number: CYIL1SM1300AA_09
• Description: LUPA-1300 1.3 MPxl High Speed CMOS Image Sensor
• Manufacturer: CYPRESS [Cypress Semiconductor]

Each output stage is designed to drive a load of 10 pF at a pixel
rate of 40 MHz. The load in the output stage determines this pixel
rate. In case the load capacitance is less than 10 pF, the load in
the output stage can increase, resulting in less power dissipation
of the output stages and consequently of the whole sensor.
Additionally, decreasing the load of the output stage allows
having more current available for the output stage to charge or
discharge the load capacitance to obtain a higher pixel rate.
To avoid variations on the supply voltage to be seen on the output
signal, a special module to stabilize the power supply is required.
This module that requires an additional supply voltage (Vstable)
allows variation on the supply voltage Voo without being seen on
the output signal.
One can also choose to have a passive load of chip instead of
the active output stage load. This deteriorates the linearity of the
output stages, but decreases the power dissipation, as the dissi-
pation in the load is external.
Frame Rate and Windowing
Frame Rate Calculation
The frame period of the LUPA-1300 sensor can be calculated as
follows:
Frame period = FOT + (Nr.Lns* (RBT + pixel period * Nr. Pxs/16)
with:
FOT: Frame Overhead Time = 1 us.
Nr. Lns: Number of Lines read out each frame (Y).
Nr. Pxs: Number of pixels read out each line (X).
RBT: Row blanking time = 200 ns (nominal; can be further
reduced).
Pixel period: clock_x period/2 (both rising and falling edge are
active edges).
- Example 1 read out of the full resolution at nominal speed (40
MHz pixel rate):
Frame period = 5 us + (1024 * (200 ns + 25 ns * 1280/16) = 2.25
ms
- Example 2 read out of 800x600 at nominal speed (40 MHz pixel
rate):
Frame period = 5 us + (600 * (200 ns + 25 ns * 800/16) = 871 us
=> 1148 fps.
- Example 3 read out of 640x480 at nominal speed (40 MHz pixel
rate):
Frame period = 5 us + (480 * (200 ns + 25 ns * 640/16) = 577 us
=> 1733 fps.
- Example 4 read out of the full resolution at nominal speed (40
MHz pixel rate) with reduced overhead time:
Frame period = 5 us + (1024 * (100 ns + 25 ns * 1280/16) = 2.15
ms
Document Number: 38-05711 Rev. *D
Note
7. The LUPA-1300 is designed to drive a capacitive load, not a resistive. When one wants to transport the output signals over long distances (more than 1 inch),
make sure to place buffers on the outputs with high input impedances (preferably >1Mohms). This is necessary because the output impedance of the LUPA-1300
is between 200-300 Ω typically.
=> 444 fps.
=> 465 fps.
X-Y Addressing and Windowing
The pixel array is readout by means of programmable X and Y
shift registers. The pixel array is scanned line-by-line and
column-by-column. The starting point in X and Y is defined
individually for each register and is determined by the address
downloaded by the Serial-Parallel Interface (SPI). Both registers
work in the same way. A sync pulse that sets the address pointer
to the starting address of each register, initializes them. A clock
pulse for the x- and y-shift register shifts the pointer individually
and makes sure that the sequential selection of the lines and
columns is correct.
Temperature Reference Circuits
Temperature Diode
The most commonly used temperature measurement is
monitoring of the junction voltage of a diode, therefore we also
added a temperature diode to measure the temperature of the
silicon die. This diode junction voltage is generated by a "small",
forward biased, constant current flow (in between 10 and 100
µA).
This junction voltage has a nearly linear relationship with the
temperature of the die with a typical sensitivity of about 430°C
per volt (2.3 mV per °C) for silicon junctions.
Temperature Module
On the same image sensor we have foreseen a module to verify
the temperature on chip and the variation of the output voltage
(dark level of the pixel array) due to a temperature variation. This
module contains a copy of the complete signal path, including a
blind pixel, the column amplifiers and an output stage. It DC
response may serve a temperature calibration for the real signal.
The temperature functionality is given in
temperature and 60
mV.
Due to different applied supply voltages, as there are: Vreset,
Vmem, Vpix an offset between the output voltage of the temper-
ature sensor and the output of a black signal of the pixel array
can occur. Depending on the working conditions of the image
sensor one can fine-tune the temperature module with its voltage
supply. In case one has a 6V signal for reset and a 4-6V signal
for Vmem, a supply voltage of 5.5V for the temperature sensor
will result in a closer match between this temperature sensor and
the black level of the image sensor. Changing the supply voltage
of the temperature sensor results only in a shift of the output
voltage therefore the supply voltage of the temperature module
can be tuned to make the output of the module equal to the dark
signal of the pixel array at a certain working temperature.
o
C we see a voltage variation of about 0.5
CYIL1SM1300AA
Figure
7. Between room
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