CYPRESS LUPA

LUPA-4000
4M Pixel CMOS Image Sensor
(SPI) interface. It is housed in a 127-pin ceramic PGA
package.
This data sheet allows the user to develop a camera-system
based on the described timing and interfacing.
Main features
Preamble
The main features of the image sensor are identified as:
• 2048 x 2048 active pixels (4M pixel resolution)
• 12 µm2 square pixels (based on the high-fill factor active
pixel sensor technology of FillFactory (US patent No.
6,225,670 and others))
• Peak QE x FF of 37.50%
• Optical format: 24,6 mm x 24,6 mm
• Pixel rate of 66 MHz using a 33 MHz system clock
• Optical dynamic range: 66 dB (2000:1) in single slope
operation and up to 90 dB in multiple slope operation
• 2 On-chip 10 bit, 33 MSamples/s ADC
• Full snapshot shutter
• Random programmable windowing and sub-sampling
modes
• 127-pin PGA package
• Binning (Voltage averaging in X-direction)
• Programmable read out direction (X and Y)
Overview
Part Number and ordering information
This document describes the interfacing and the driving of the
LUPA-4000 image sensor. This 4 mega-pixel CMOS active
pixel sensor features synchronous shutter and a maximal
frame-rate of 15 fps in full resolution. The readout speed can
be boosted by means of sub sampling and windowed Region
Of Interest (ROI) readout. High dynamic range scenes can be
captured using the double and multiple slope functionality.
The sensor can be used with one or two outputs. Two on chip
10-bit ADC's can be used to convert the analog data to a 10-bit
digital word stream. The sensor uses a 3-wire Serial-Parallel
Cypress Semiconductor Corporation
Document Number: 38-05712 Rev. *B
•
Name
Package
CYIL1SM4000AA-GDC 127 pin ceramic
PGA
Monochrome/color
Monochrome
The LUPA-4000 is also available in color or monochrome
without the cover glass. Please contact Cypress for more
information.
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised Januari 4, 2007
LUPA-4000
TABLE OF CONTENTS
Preamble ........................................................................................................................................................... 1
Overview ...................................................................................................................................................... 1
Main features ............................................................................................................................................... 1
Part Number and ordering information.......................................................................................................... 1
Specifications ................................................................................................................................................... 4
General specifications .................................................................................................................................. 4
Electro-optical specifications ........................................................................................................................ 4
Features and general specifications ............................................................................................................ 6
Electrical specifications ................................................................................................................................ 7
Sensor architecture .......................................................................................................................................... 8
The 6-T pixel ................................................................................................................................................ 8
Frame rate and windowing ........................................................................................................................... 9
Output amplifier ............................................................................................................................................ 9
Pixel array drivers ........................................................................................................................................ 10
Column amplifiers ........................................................................................................................................ 10
Analog to Digital Converter .......................................................................................................................... 10
Synchronous shutter .................................................................................................................................... 11
Non-destructive readout (NDR) ................................................................................................................... 12
Operation and signalling .............................................................................................................................. 12
Pixel array signals ........................................................................................................................................ 14
Timing and read out of the image sensor ...................................................................................................... 16
Timing of the pixel array ............................................................................................................................... 16
Read out of the image sensor ...................................................................................................................... 18
Serial-Parallel-Interface (SPI) ...................................................................................................................... 24
Pin list ................................................................................................................................................................ 25
Geometry and mechanical specifications ...................................................................................................... 29
Bare die ........................................................................................................................................................ 29
Package drawing ......................................................................................................................................... 30
Bonding pads ............................................................................................................................................... 32
Bonding diagram .......................................................................................................................................... 33
Glass transmittance ..................................................................................................................................... 34
Handling and soldering precautions .............................................................................................................. 35
Ordering Information .................................................................................................................................... 35
Disclaimer .................................................................................................................................................... 35
APPENDIX A: LUPA-4000 evaluation system ................................................................................................ 36
APPENDIX B: Frequently Asked Questions ................................................................................................... 37
Document History Page ................................................................................................................................... 38
LIST OF FIGURES
Spectral response curve ..................................................................................................................................... 5
Photo-voltaic response curve ............................................................................................................................. 6
Block diagram of the image sensor .................................................................................................................... 8
6T-pixel architecture ........................................................................................................................................... 8
Output stage architecture ................................................................................................................................... 9
ADC timing ......................................................................................................................................................... 10
In- and external ADC connections ...................................................................................................................... 11
Document Number: 38-05712 Rev. *B
Page 2 of 38
LUPA-4000
Synchronous shutter operation ........................................................................................................................... 11
Principle of non-destructive readout. .................................................................................................................. 12
Internal timing of the pixel................................................................................................................................... 14
Integration and read out in parallel ..................................................................................................................... 16
Integration and readout sequentially .................................................................................................................. 16
Timing of the pixel array ...................................................................................................................................... 17
Readout of the image sensor. F.O.T ................................................................................................................... 18
X- and Y-addressing ........................................................................................................................................... 19
X-addressing. From bottom to top ....................................................................................................................... 20
Output signal related to Clock_x signal ............................................................................................................... 21
Standard timing for the R.O.T. Only pre_col and Norowsel control signals are required .................................... 22
Reduced standard ROT by means of Sh_col signal............................................................................................ 22
X- and Y-addressing with precharging of the buses ........................................................................................... 23
SPI block diagram and timing ............................................................................................................................. 24
Die figure of the LUPA-4000 ............................................................................................................................... 29
Package drawing of the LUPA-4000 package .................................................................................................... 30
LUPA-4000 package specifications with die ....................................................................................................... 31
Placing of the bonding pads on the LUPA-4000 package .................................................................................. 32
Bonding pads diagram of the LUPA-4000 package ........................................................................................... 33
Transmission characteristics of the D263 glass used as protective cover for the LUPA-4000 sensors. ............ 34
Content of the LUPA-4000 evaluation kit ........................................................................................................... 36
Dual slope diagram ............................................................................................................................................. 37
LIST OF TABLES
General specifications ........................................................................................................................................ 4
Electro-optical specifications .............................................................................................................................. 4
Features and general specifications ................................................................................................................... 6
Recommended operation conditions .................................................................................................................. 7
Frame rate as function of ROI read out and/or sub sampling ............................................................................. 9
ADC specifications ............................................................................................................................................. 10
Advantages and disadvantages of non-destructive readout. .............................................................................. 12
Power supplies ................................................................................................................................................... 12
Overview of the power supplies related to the pixel signals ............................................................................... 13
Overview of bias signals ..................................................................................................................................... 13
Overview of the in- and external pixel array signals ........................................................................................... 15
Timing specifications .......................................................................................................................................... 17
Read-out timing specifications ............................................................................................................................ 19
Read-out timing specifications with precharching of the buses .......................................................................... 23
SPI parameters ................................................................................................................................................... 24
Document Number: 38-05712 Rev. *B
Page 3 of 38
LUPA-4000
Specifications
General specifications
Table 1. General specifications
Parameter
Specification
Remarks
Pixel architecture
6T-pixel
Based on the high fill-factor active pixel sensor technology of FillFactory
Pixel size
12 µm x 12 µm
Resolution
2048 x 2048
The resolution and pixel size results in a 24,6 mm x 24,6 mm optical
active area.
Pixel rate
66 MHz
Using a 33 MHz system clock and 1 or 2 parallel outputs.
Shutter type
Pipelined snapshot shutter
Full snapshot shutter (integration during read out is possible).
Full frame rate
15 frames/second
Frame rate increase possible with ROI read out and/or sub sampling.
Electro-optical specifications
Overview
Table 2. Electro-optical specifications
Parameter
FPN
Specification
<1.25% RMS
Remarks
of max. output swing
PRNU
<2.5% RMS
at 25% and 75% (% of the signal)
Conversion gain
13.5 uV/electron
@ output (measured).
Output signal amplitude
1V
Converted by 2 on-chip 10-bit ADC's in 2x10 parallel digital
outputs. Or to be used with external ADC's
Saturation charge
80.000 e-
Sensitivity
2090 V.m2/W.s
Average white light.
11.61 V/lux.s
Visible band only (180 lx = 1 W/m2).
Peak QE * FF
Peak SR * FF
37.5%
0.19 A/W
Average QE*FF = 35%.
Average SR*FF = 0.15 A/W.
See spectral response curve.
Dark current (@ 21 °C)
<140 mV/s
or 10000 e-/s
Noise electrons
< 40 e-
S/N ratio
2000:1
Spectral sensitivity range
400 - 1000 nm
Parasitic sensitivity
< 1/5000
MTF
64%
Power dissipation
<200 mWatt
Document Number: 38-05712 Rev. *B
66 dB.
I.e. sensitivity of the storage node during read out (after
integration).
Typical (without ADC's).
Page 4 of 38
LUPA-4000
Spectral response curve
Figure 1. Spectral response curve
QE 40%
0.20
QE 30%
QE 25%
0.18
QE 20%
0.16
Spectral response [A/W]
0.14
0.12
0.10
QE 10%
0.08
0.06
0.04
0.02
0.00
400
500
600
700
800
900
1000
Wavelength [nm]
Figure 1 shows the spectral response characteristic. The
curve is measured directly on the pixels. It includes effects of
non-sensitive areas in the pixel, e.g. interconnection lines. The
sensor is light sensitive between 400 and 1000 nm. The peak
Document Number: 38-05712 Rev. *B
QE * FF is 37.5% approximately between 500 and 700 nm. In
view of a fill factor of 60%, the QE is thus larger than 60%
between 500 and 700 nm.
Page 5 of 38
LUPA-4000
Photo-voltaic response curve
Figure 2. Photo-voltaic response curve
1.2
1
Output swing [V]
0.8
0.6
0.4
0.2
0
0
20000
40000
60000
80000
100000
120000
140000
# electrons
Figure 2 shows the pixel response curve in linear response
mode. This curve is the relation between the electrons
detected in the pixel and the output signal. The resulting
voltage-electron curve is independent of any parameters. The
voltage to electrons conversion gain is 13.5 µV/electron.
Note that the upper part of the curve (near saturation) is
actually a logarithmic response.
Features and general specifications
Table 3. Features and general specifications
Feature
Electronic shutter type
Specification/Description
Full snapshot shutter (integration during read out is possible).
Windowing (ROI)
Randomly programmable ROI read out.
Sub-sampling and binning modes
2:1 subsampling and voltage averaging is possible (only in the X-direction).
Read out direction
Read out direction can be reversed in X and Y.
Extended dynamic range
Multiple slope (up to 90 dB optical dynamic range).
Analog output
The output rate of 66 Mpixels/s can be achieved with either 1 or 2 analog outputs.
Digital output
2 on-chip 10-bit ADC's @ 33 Msamples/s.
Supply voltage VDD
Nominal 2.5V (some supplies require 3.3V).
Logic levels
3.3V.
Operational temperature range
0°C to 60°C; with degradation of dark current.
Interface
Serial-to Parallel Interface (SPI).
Package
127 pin PGA package
Power dissipation
<200 mW
Mass
<100g
Document Number: 38-05712 Rev. *B
Page 6 of 38
LUPA-4000
Table 3. Features and general specifications (continued)
Feature
Specification/Description
Output amplifiers
Differential
External output load
R > 10 kΩ
C < 20 pF (<10 pF is advised)
Number of outputs
1 at 66 Mpixels/sec
2 at 33 Mpixels/sec
Electrical specifications
or output. ± 50 mA
Absolute maximum ratings
TL Lead temperature (5 seconds soldering). 350 °C
• Absolute Ratings are those values beyond which damage
to the device may occur.
• VDD = VDDD = VDDA (VDDD is supply to digital circuit,
VDDA to analog circuit).
VDD DC supply voltage -0.5 to 4.5 V
VIN DC input voltage -0.5 to 3.8 V
VOUT DC output voltage -0.5 to 3.8 V
IIO DC current drain per pin; any single input
Recommended operating conditions
Table 4. Recommended operation conditions
Symbol
Parameter
Min.
Typ.
Max.
Unit
Vaa
Power supply column read out module
2.5
Va3
Power supply column read out module
3.3
V
Vdd
Power supply digital modules
2.5
V
Voo
Power supply output stages
2.5
V
3.3
V
Vres
Power supply reset drivers
2.5
3.5
3.8
V
Vres_ds
Power supply multiple slope reset driver
2.0
2.5
3.3
V
Vmem_h
Power supply memory element (high level)
2.5
3.3
3.5
V
Vmem_l
Power supply memory element (low level)
2.0
2.6
3.0
V
Vpix
Power supply pixel array
2.0
2.6
3.3
V
Vpre_l
Power supply for Precharge off-state
–0.4
0
0
V
TA
Commercial operating temperature.
0
30
60
°C
Notes
1. All parameters are characterized for DC conditions after thermal equilibrium has been established.
2. Unused inputs must always be tied to an appropriate logic level, e.g. either VDD or GND.
3. This device contains circuitry to protect the inputs against damage due to high static voltages or electric fields; however it is recommended that normal precautions
be taken to avoid application of any voltages higher than the maximum rated voltages to this high impedance circuit.
Document Number: 38-05712 Rev. *B
Page 7 of 38
LUPA-4000
Sensor architecture
A schematic drawing of the architecture is given in the block
diagram below. The image core consists of a pixel array, one
X- and two Y-addressing registers (only one drawn), pixel
array drivers and column amplifiers. The image sensor of 2048
* 2048 pixels is read out in progressive scan. One or two output
amplifiers read out the image sensor. The output amplifiers are
working at 66 MHz pixel rate nominal speed or each at 33 MHz
pixel rate in case the 2 output amplifiers are used to read out
the imager. The complete image sensor has been designed for
operation up to 66 MHz.
The structure allows having a programmable addressing in the
x-direction in steps of 2 and in the y-direction in steps of 2 (only
even start addresses in X- and Y-direction are possible). The
starting point of the address is uploadable by means of the
Serial-Parallel Interface (SPI)
Figure 3. Block diagram of the image sensor
eos_y
y shift register
select drivers
On chip drivers
Reset, mem_hl,
precharge, sample
pixel array
2048 * 2048
Column amplifiers
Clk_y sync_y
eos_x
X shift register
Clk_x
SPI
Logic blocks
DA C
2 differential
outputs
sync_x
The 6-T pixel
To obtain the global shutter feature combined with a high
sensitivity and good Parasitic Light Sensitivity (PLS), the pixel
architecture given in the figure below is implemented.
Figure 4. 6T-pixel architecture
Vpix
R eset
Document Number: 38-05712 Rev. *B
Vmem
Sample
Row-Select
Page 8 of 38
LUPA-4000
This pixel architecture is designed in a 12 * 12 µm2 pixel pitch.
The pixel is designed to meet the specifications as described
in Table 1, Table 2, and Table 3.
Frame rate and windowing
Frame rate
To obtain a frame rate a 15 frames/sec, one needs 1 output amplifier, working at 66 MHz pixel rate or 2 output amplifiers working
at 33 MHz each (assuming a Row Overhead Time (ROT) of 200 nsec).
The frame period of the LUPA-4000 sensor can be calculated as follows:
Frame period = FOT + (Nr. Lines * (ROT + pixel period * Nr. Pixels)
with: FOT: Frame Overhead Time = 5 µs.
Nr. Lines: Number of Lines read out each frame (Y).
Nr. Pixels: Number of pixels read out each line (X).
ROT: Row Overhead Time = 200 ns (nominal; can be further reduced).
Pixel period: 1/66 MHz = 15.15 ns.
Example read out of the full resolution at nominal speed (66 MHz pixel rate):
Frame period = 5 us + (2048 * (200 ns + 15.15 ns * 2048) = 64 ms
ROI read out (windowing)
Windowing can easily be achieved by a serial-parallel
uploadable interface in which the starting point of the x- and
y-address is uploaded. This downloaded starting point initiates
the shift register in the x- and y- direction triggered by the
Sync_x and Sync_y pulse. The minimum step size for the
=> 15 fps.
x-address and the y-address is 2 (only even start addresses
can be chosen). The size of both address registers is 10 bits.
When for instance the addresses 0000000001 and
0000000001 are uploaded, the readout will start at line 2 and
column 2.
Table 5. Frame rate as function of ROI read out and/or sub sampling
Image Resolution (X*Y)
Frame rate [frames/s]
Frame readout time [ms]
Comment
2048 x 2048
15
67
Full resolution.
1024 x 2048
31
32
Subsample in X-direction.
1024 x 1024
62
16
ROI read out.
640 x 480
210
4.7
ROI read out.
Output amplifier
1 output amplifier working at 66 Mpixels/sec is required to
bring the whole pixel array of 2048 by 2048 pixels at the
required frame rate to the outside world. A second output
stage is also foreseen to convert the analog data on-chip by 2
10-bit ADC's each working at 33 MHz. By having a second
output stage working in parallel, the pixel rate can be more
relaxed to 33 MHz for both output amplifiers. Using only one
output-stage, the output signal will be the result of multiplexing
between the 2 internal buses. When using 2 output-stages,
both outputs will be in phase.
Each output-stage has 2 outputs. One output is the pixel
signal; the second output is a DC signal which offset can be
programmed using a 7-bit word. The DC signal can be used
for common mode rejection between the 2 signals. The
disadvantage is an increase in power dissipation however this
can be reduced by setting the highest DAC voltage by means
of the SPI
Figure 5. Output stage architecture.
Image sensor
Out1: Pixel signal
7bits
SPI
Document Number: 38-05712 Rev. *B
DAC
Out2: dc signal
Page 9 of 38
LUPA-4000
The output voltage of Out1 will be between 1.3V (dark level)
and 0.3V (white level) and depends on process variations and
voltage supply settings. The output voltage of Out2 is
determined by the DAC.
Pixel array drivers
We have foreseen on this image sensor on chip drivers for the
pixel array signals. Not only the driving on system level is easy
and flexible, also the maximum currents applied to the sensor
are controlled on chip. This means that the charging on sensor
level is fixed and that the sensor cannot be overdriven from
externally. In the paragraph on the timing, the operation of the
on-chip drivers is explained more in detail.
Column amplifiers
The column amplifiers are designed for minimum power dissipation and minimum loss of signal for this reason multiple
biasing signals are needed.
ADC should be tied externally to the outputs of the output
amplifiers.
One ADC will sample the even columns and the other one will
sample the odd columns. Although the input range of the ADC
is between 1V and 2V and the output range of the analog
signal is only between 0.3V and 1.3V, the analog output and
digital input may be tied to each other directly. This is possible
because there is an on chip level-shifter located in front of the
ADC to lift up the analog signal to the ADC range.
Table 6. ADC specifications
Parameter
Specification
Input range
1 - 2V (*)
Quantization
10 Bits
Nominal data rate
33 Msamples/s
DNL (linear conversion mode)
Typ. < 0.4 LSB RMS
The column amplifiers also have the "voltage-averaging"
feature integrated. In case of voltage averaging mode, the
voltage average between 2 columns is taken and read out. In
this mode only 2:1 pixels have to be read out.
INL (linear conversion mode)
Typ. < 3.5
To achieve the voltage-averaging mode, an additional external
digital signal called "voltage-averaging" is required in
combination with a bit from the SPI.
Analog to Digital Converter
The LUPA4000 has a two 10 bit flash analog digital converters
running nominally at 33 Msamples/s. The ADC's are
electrically separated from the image sensor. The inputs of the
LSB
Input capacitance
< 2 pF
Power dissipation @ 33 MHz
50 mW
Conversion law
Linear/Gamma-corrected
ADC timing
The ADC converts the pixel data on the falling edge of the
ADC_CLOCK but it takes 2 clock cycles before this pixel data
is at the output of the ADC. This pipeline delay is shown in
Figure .
Figure 6. ADC timing
Note
4. The internal ADC range will be typ. 50 mV lower then the external applied ADC_VHIGH and ADC_VLOW voltages due to voltage drops over parasitic internal
resistors in the ADC.
Document Number: 38-05712 Rev. *B
Page 10 of 38
LUPA-4000
Setting of the ADC reference voltages
Figure 7. In- and external ADC connections
2.5V
RHIGH_ADC
REF_HIGH ~ 2 V
external
internal
RADC
REF_LOW ~ 1 V
external
RLOW_ADC
The internal resistor RADC has a value of approximately 300Ω.
Resistor
This results in the values for the external resistors:
Resistor
Value (Ω)
RADC_VHIGH
75
RADC
300
Value (Ω)
RADC_VLOW
220
The values of the resistors depend on the value of RADC. The
voltage difference between ADC_VLOW and ADC_VHIGH
should be at least 1.0V to assure proper working of the ADC.
Synchronous shutter
In a synchronous (snapshot) shutter light integration takes
place on all pixels in parallel, although subsequent readout is
sequential.
Figure 8. Synchronous shutter operation
COMMON SAMPLE&HOLD
Flash could occur here
COMMON RESET
Line number
Time axis
Integration time
Document Number: 38-05712 Rev. *B
Burst Readout time
Page 11 of 38
LUPA-4000
Non-destructive readout (NDR)
Figure 8 shows the integration and read out sequence for the
synchronous shutter. All pixels are light sensitive at the same
period of time. The whole pixel core is reset simultaneously
and after the integration time all pixel values are sampled
together on the storage node inside each pixel. The pixel core
is read out line by line after integration. Note that the
integration and read out cycle can occur in parallel or in
sequential mode. (ref. 4. Timing and read out of the image
sensor)
The sensor can also be read out in a non-destructive way. After
a pixel is initially reset, it can be read multiple times, without
resetting. The initial reset level and all intermediate signals can
be recorded. High light levels will saturate the pixels quickly,
but a useful signal is obtained from the early samples. For low
light levels, one has to use the later or latest samples.
Figure 9. Principle of non-destructive readout
time
•
•
•
•
•
Essentially an active pixel array is read multiple times, and
reset only once. The external system intelligence takes care
of the interpretation of the data. Table 7 summarizes the
advantages and disadvantages of non-destructive readout.
Table 7. Advantages and disadvantages of non-destructive readout.
Advantages
Power supplies and grounds
Biasing and Analog signals
Pixel array signals
Digital signals
Test signals
Power supplies and ground
Disadvantages
Low noise - as it is true CDS.
System memory required
to record the reset level and
the intermediate samples.
High sensitivity - as the
conversion capacitance is kept
rather low.
Requires multiples
readings of each pixel, thus
higher data throughput.
Every module on chip, as there are: column amplifiers, output
stages, digital modules, drivers has its own power supply and
ground. Off chip the grounds can be combined, but not all
power supplies may be combined. This results in several
different power supplies, but this is required to reduce
electrical cross-talk and to improve shielding, dynamic range
and output swing.
Requires system level
High dynamic range - as the
results includes signal for short digital calculations.
and long integrations times.
On chip we have the ground lines of every module which are
kept separately to improve shielding and electrical cross talk
between them.
Operation and signalling
An overview of the supplies is given in Table 8 and Table 9.
Table 9 summarizes the supplies related to the pixel array
signals, where Table 8 summarizes the supplies related with
all other modules
One can distinguish the different signals into different groups:
Table 8. Power supplies
Name
DC Current
Max.current
Typ.
Max.
Description
Vaa
7 mA
50 mA
2.5V
Power supply column readout module.
Va3
10 mA
50 mA
3.3V
Vdd
1 mA
200 mA
2.5V
Power supply digital modules
Voo
20 mA
20 mA
2.5V
Power supply output stages
3.3V
Power supply column readout module.
Should be tuneable to 3.3V max.
Vdda
1 mA
200 mA
2.5V
Analog supply of ADC circuitry
Vddd
1 mA
200 mA
2.5V
Digital supply of ADC circuitry
Document Number: 38-05712 Rev. *B
Page 12 of 38
LUPA-4000
Table 9. Overview of the power supplies related to the pixel signals
Name
DC current
Max. current
Min.
Typ.
Max.
Description
Vres
1 mA
200 mA
2.5V
3.5V
3.8V
Power supply reset drivers.
Vres_ds
1 mA
200 mA
2.0V
2.5V
3.3V
Power supply dual slope reset drivers.
Vmem_h
1 mA
200 mA
2.5V
3.3V
3.5V
Power supply memory elements in pixel for
high voltage level
Vmem_l
1 mA
200 mA
2.0V
2.5 V
3.0V
Power supply memory elements in pixel for
low voltage level. Should be tuneable
Vdd
1 mA
200 mA
2.0V
2.5V
3.0V
Power supply for Sample
Vpix
12 mA
500 mA
2.0V
2.5V
3.3V
Power supply pixel array. Should be
tuneable to 3.3V
Vpre_l
1 mA
200 mA
–400 mV
0V
0V
Power supply for Precharge in off-stat. May
be connected to ground.
The maximum currents mentioned in Table 8 and Table 9 are
peak currents which occur once per frame (except for Vres_ds
in multiple slope mode). All power supplies should be able to
deliver these currents except for Vmem_l and Vpre_l, which
must be able to sink this current.
The maximum peak current for Vpix should not be higher than
500 mA. It is important to notice that no power supply filtering
on chip is implemented and that noise on these power supplies
can contribute immediately to the noise on the signal.
Especially the voltage supplies Vpix and Vaa are important to
be well noise free.
Start-up sequence
The LUPA-4000 will go in latch up (draw high current) as soon
as all power supplies are turned on at the same time. The
sensor will come out of latch-up and start working normally as
soon as it is being clocked. A power supply with a 400 mA limit
is recommended to avoid damage to the sensor. It is
recommended to avoid the time that the device is in the
latch-up state, so clocking of the sensor should start as soon
as possible (i.e. as soon as the system is turned on).
• Apply Vdd
• Apply clocks and digital pulses to the sensor to count 2048
clocks and 2048 clock_y pulses to empty the shift registers
• Apply other supplies
Biasing and analog signals
The analog output levels that may be expected are between
0.3V for a white, saturated, pixel and 1.3V for a black pixel.
2 Output stages are foreseen, each consisting of 2 output
amplifiers, resulting in 4 outputs. 1 Output amplifier is used for
the analog signal resulting from the pixels. The second
amplifier is used for a dc reference signal. The dc-level from
the buffer is defined by a DAC, which is controlled by a 7-bit
word downloaded in the SPI. Additionally, an extra bit in the
SPI defines if 1 output or the 2 output stages are used.
Table 10 summarizes the biasing signals required to drive this
image sensor. For optimisation reasons of the biasing of the
column amplifiers with respect to power dissipation, we need
several biasing resistors. This optimisation results in an
increase of signal swing and dynamic range.
In order to completely avoid latch-up of the image sensor, the
next sequence should be taken into account:
Table 10. Overview of bias signals
Signal
Out_load
Comment
Related module
DC-level
Connect with 60 KΩ to Voo and capacitor of 100 nF to Gnd
Output stage
0.7 V
dec_x_load
Connect with 2 MΩ to Vdd and capacitor of 100 nF to Gnd
X-addressing
0.4 V
muxbus_load
Connect with 25 KΩ to Vaa and capacitor of 100 nF to Gnd
Multiplex bus
0.8 V
nsf_load
Connect with 5 KΩ to Vaa and capacitor of 100 nF to Gnd
Column amplifiers
1.2 V
uni_load_fast
Connect with 10 KΩ to Vaa and capacitor of 100 nF to Gnd
Column amplifiers
1.2 V
uni_load
Connect with 1 MΩ to Vaa and capacitor of 100 nF to Gnd
Column amplifiers
0.5 V
pre_load
Connect with 3 KΩ to Vaa and capacitor of 100 nF to Gnd
Column amplifiers
1.4 V
col_load
Connect with 1 MΩ to Vaa and capacitor of 100 nF to Gnd
Column amplifiers
0.5 V
dec_y_load
Connect with 2 MΩ to Vdd and capacitor of 100 nF to Gnd
Y-addressing
0.4 V
psf_load
Connect with 1 MΩ to Vaa and capacitor of 100 nF to Gnd
Column amplifiers
0.5 V
Document Number: 38-05712 Rev. *B
Page 13 of 38
LUPA-4000
Table 10. Overview of bias signals (continued)
Signal
precharge_bias
Comment
Related module
Connect with 1kΩ to Vdd and capacitor of at least 200 nF to
Gnd.
Each biasing signal determines the operation of a corresponding module in the sense that it controls speed and dissipation. Some modules have 2 biasing resistors: one to achieve
the high speed and another to minimize power dissipation.
Pixel array signals
The Pixel array of the image sensor requires digital control
signals and several different power supplies. This paragraph
explains the relation between the control signals and the
applied supplies and the internal generated pixel array signals.
From Figure 9 one can see that the internal generated pixel
array signals are Reset, Sample, Precharge, Vmem and
Row_select. These are internal generated signals derived by
on chip drivers from external applied signals. Row_select is
generated by the y addressing and will not be discussed in this
paragraph.
The function of each of the signals is:
Reset: Resets the pixel and initiates the integration time. If
reset is high than the photodiode is forced to a certain voltage,
depending on Vpix, which is the pixel supply; and depending
on the high level of reset signal. The higher these signals or
supplies are, the higher the voltage-swing. The limitation on
the high level of Reset and Vpix is 3.3V. Nevertheless, it has
Pixel drivers
DC-level
1.4V
no sense increasing Vpix without increasing the reset level.
The opposite does make sense. Additionally, it is this reset
pulse that also controls the dual or multiple slope feature
inside the pixel. By giving a reset pulse during integration, but
not at full reset level, the photodiode is reset to a new value,
only if his value is sufficient decreased due to light illumination.
The low level of reset is 0V, but the high level is 2.5V or higher
(3.3V) for the normal reset and a lower (<2.5V) level for the
multiple slope reset.
Precharge: Precharge serves as a load for the first source
follower in the pixel and is activated to overwrite the current
information on the storage node by the new information on the
photodiode. Precharge is controlled by an external digital
signal between 0 and 2.5V.
Sample: Samples the photodiode information onto the
memory element. This signal is also a standard digital level
between 0 and 2.5V.
Vmem: this signal increases the information on the memory
element with a certain offset. This way one can increase the
output voltage variation. Vmem changes between Vmem_l
(2.5V) and Vmem_h (3.3V).
Figure 10. Internal timing of the pixel. Levels are defined by the pixel array voltage supplies (For the correct polarities
of the signals refer to Table 11)
The signals in Figure 10 are generated from the on chip
drivers. These on chip drivers need 2 types of signals to
generate the exact type of signal. It needs digital control
signals between 0 and 3.3V (internally converted to 2.5V) with
normal driving capability and power supplies. The control
signals are required to indicate the moment they need to occur
and the power supplies indicate the level.
Vmem is made of a control signal Mem_hl and 2 supplies
Vmem_h and Vmem_l. If the signal Mem_hl is the logic "0"
Document Number: 38-05712 Rev. *B
than the internal signal Vmem is low, if Mem_hl is logic "1" the
internal signal Vmem is high.
Reset is made by means of 2 control signals: Reset and
Reset_ds and 2 supplies: Vres and Vres_ds. Depending on
the signal that becomes active, the corresponding supply level
is applied to the pixel.
Table 11 summarizes the relation between the internal and
external pixel array signals.
Page 14 of 38
LUPA-4000
Table 11. Overview of the in- and external pixel array signals
Internal Signal
Vlow
Vhigh
Precharge
0
0.45V
Sample
0
Reset
0
Vmem
2.0- 2.5V
External control signal
Low DC-level
High DC-level
Precharge (AL)
Vpre_l
Controlled by bias-resistor
2.5V
Sample (AL)
Gnd
Vdd
2.5 - 3.3V
Reset (AH) & Reset_ds
(AH)
Gnd
Vres & Vres_ds
2.5-3.3V
Mem_hl (AL)
Vmem_l
Vmem_h
In case the dual slope operation is desired, one needs to give
a second reset pulse to a lower reset level during integration.
This can be done by the control signal Reset_ds and by the
power supply Vres_ds that defines the level to which the pixel
has to be reset.
Note that Reset is dominant over Reset_ds, which means that
the high voltage level will be applied for reset, if both pulses
occur at the same time.
Note that multiple slopes are possible having multiple
Reset_ds pulses with a lower Vres_ds level for each pulse
given within the same integration time
The rise and fall times of the internal generated signals are not
very fast (200 nsec). In fact they are made rather slow to limit
the maximum current through the power supply lines
(Vmem_h, Vmem_l, Vres, Vres_ds, Vdd). Current limitation of
those power supplies is not required. Nevertheless, it is
advisable to limit the currents not higher than 400 mA.
The power supply Vmem_l must be able to sink this current
because it must be able to discharge the internal capacitance
from the level Vmem_h to the level Vmem_l. The external
control signals should be capable of driving input capacitance
of about 10 pF.
Digital signals
The digital signals control the readout of the image sensor.
These signals are:
• Sync_y (AH): Starts the readout of the frame. This pulse
synchronises the y-address register: active high. This signal
is at the same time the end of the frame or window and
determines the window width.
• Clock_y (AH): Clock of the y-register. On the rising edge of
this clock, the next line is selected.
• Sync_x (AH): Starts the readout of the selected line at the
address defined by the x-address register. This pulse
synchronises the x-address register: active high. This signal
is at the same time the end of the line and determines the
window length.
• Clock_x (AH): Determines the pixel rate. A clock of 33 MHz
is required to achieve a pixel rate of 66MHz.
• Spi_data (AH): the data for the SPI
• Spi_clock (AH): clock of the serial parallel interface. This
clock downloads the data into the SPI register.
• Spi_load (AH): when the SPI register is uploaded, then the
data will be internally available on the rising edge of
SPI_load.
• Sh_kol (AL): control signal of the column readout. Is used
in sample & hold mode and in binning mode.
• Norowsel (AH): Control signal of the column readout. (See
timing).
• Pre_col (AL): Control signal of the column readout to reduce
row blanking time.
• Voltage averaging (AH): Signal required obtaining voltage
averaging of 2 pixels.
Test signals
The test structures implemented in this image sensor are:
• Array of pixels (6*12) which outputs are tied together: used
for spectral response measurement.
• Temperature diode (2): Apply a forward current of 10-100
µA and measure the voltage VT of the diode. VT varies linear
with the temperature (VT decreases with approximately 1,6
mV/°C).
• End of scan pulses (do not use to trigger other signals):
• Eos_x: end of scan signal: is an output signal, indicating
when the end of the line is reached. Is not generated when
doing windowing.
• Eos_y: end of scan signal: is an output signal, indicating
when the end of the frame is reached. Is not generated
when doing windowing.
• Eos_spi: output signal of the SPI to check if the data is
transferred correctly through the SPI.
Notes
5. AH: Active High
6. AL: Active Low
Document Number: 38-05712 Rev. *B
Page 15 of 38
LUPA-4000
Timing and read out of the image sensor
The timing of the LUPA-4000 sensor consists of 2 parts. The
first part is related with the control of the pixels, the integration
time and the signal level. The second part is related with the
readout of the image sensor. As this image sensor is able for
full synchronous shutter, integration time and readout can be
in parallel or sequential.
In the parallel mode the integration time of the frame I is
ongoing during readout of frame I-1. Figure 11 shows this
parallel timing structure
Figure 11. Integration and read out in parallel
Read frame I
Read frame I + 1
Integration I + 1
Integration I + 2
The control of the readout of the frame and of the integration
time are independent of each other with the only exception that
the end of the integration time from frame I+1 is the beginning
of the readout of frame I+1.
The LUPA-4000 sensor also can be used in sequential mode
(triggered snapshot mode) where readout and integration will
be sequentially. Figure 12 shows this sequential timing
sequence.
Figure 12. Integration and readout sequentially
Integration I
Read frame I
Timing of the pixel array
The first part of the timing is related with the timing of the pixel
array. This implies the control of the integration time, the
synchronous shutter operation and the sampling of the pixel
information onto the memory element inside each pixel. The
signals needed for this control are described in the previous
paragraph 3.9 and in Figure 10.
Document Number: 38-05712 Rev. *B
Integration I + 1
Read frame I + 1
Figure shows the external applied signals required to control
the pixel array. At the end of the integration time from frame
I+1, the signals Mem_hl, Precharge and Sample have to be
given. The reset signal controls the integration time, which is
defined as the time between the falling edge of reset and the
rising edge of sample.
Page 16 of 38
LUPA-4000
Figure 13. Timing of the pixel array: The integration time is determined by the falling edge of the reset pulse. The longer
the pulse is high, the shorter the integration time. At the end of the integration time, the information has to be stored
onto the memory element for readout.
Timing specifications for each signal are:
Table 12. Timing specifications
Symbol
Name
Value
a
Mem_HL
5 - 8,2 µsec
b
Precharge
3 - 6 µsec
c
Sample
5 - 8 µsec
d
Precharge-Sample
> 2 µsec
e
Integration time
> 1 µsec
• Falling edge of Precharge is equal or later than falling edge
of Vmem.
• Sample is overlapping with precharge.
• Rising edge of Vmem is more than 200 nsec after rising
edge of Sample.
• Rising edge of reset is equal or later than rising edge of
Vmem
The timing of the pixel array is straightforward. Before the
frame is read, the information on the photodiode needs to be
stored onto the memory element inside the pixels. This is done
by means of the signals Mem_hl, Precharge and Sample.
When precharge is activated it serves as a load for the first
Document Number: 38-05712 Rev. *B
source follower in the pixel. Sample stores the photodiode
information onto the memory element. Mem_hl pumps up this
value to reduce the loss of signal in the pixel and this signal
must be the envelop of Precharge and Sample. After Mem_hl
is high again, the readout of the pixel array can start. The
frame blanking time or frame overhead time is thus the time
that Mem_hl is low, which is about 5 µsec. Once the readout
starts, the photodiodes can all be initialised by reset for the
next integration time. The minimal integration time is the
minimal time between the falling edge of reset and the rising
edge of sample. Keeping the slow fall times of the corresponding internal generated signals in mind, the minimal
integration time is about 2 µsec.
Page 17 of 38
LUPA-4000
An additional reset pulse of minimum 2 µsec can be given
during integration by asserting Reset_ds to implement the
double slope integration mode.
Read out of the image sensor
As soon as the information of the pixels is stored in to the
memory element of each pixel, this information can be readout
sequentially. As seen in the previous section, integration and
readout can also be done in parallel.
The readout timing is straightforward and is basically
controlled by means of sync and clock pulses.
Figure 14 shows the top level concept of this timing. The
readout of a frame consists of the frame overhead time, the
selection of the lines sequentially and the readout of the pixels
of the selected line
Figure 14. Readout of the image sensor. F.O.T: Frame overhead time. R.O.T: Row overhead time. L: selection of line, C:
Selection of column
Read frame I
Integration I + 2
Readout Lines
F.O.T
L1
L2
L3
L2048
Readout pixels
R.O.T
C1
C2
The readout of an image consists of the FOT (Frame overhead
time) and the sequential selection of all pixels. The FOT is the
overhead time between 2 frames to transfer the information on
the photodiode to the memory elements. From Figure 13 it
should be clear that this time is the time that Mem_hl is low
(typically 5 µs). After the FOT the information is stored into the
memory elements and a sequential selection of rows and
columns makes sure the frame is read.
X- and Y- addressing
To readout a frame the lines are selected sequentially.
Figure 15 gives the timing to select the lines sequentially. This
Document Number: 38-05712 Rev. *B
C2048
is done by means of a Clock_y and a Sync_y signal. The
Sync_y signals synchronises the y-addressing and initialises
the y-address selection registers. The start address is the
address downloaded in the SPI multiplied by 2.
On the rising edge of Clock_y the next line is selected. The
Sync_y signal is dominant and from the moment it occurs the
y-address registers are initialised. If a Sync_y pulse is given
before the end of the frame is reached, only a part of the frame
will be read. To obtain a correct initialisation Sync_y must
contain at least 1 rising edge of Clock_y when it is active.
Page 18 of 38
LUPA-4000
Figure 15. X- and Y-addressing
Table 13. Read-out timing specifications
Symbol
Name
Value
a
Sync_Y
>20 ns
b
Sync_Y-Clock_Y
>0 ns
c
Clock_Y-Sync_Y
>0 ns
d
NoRowSel
>50 ns
e
Pre_col
>50 ns
f
Sh_col
200 ns (more information on this timing
can be found in section 4.2.2.a)
g
Voltage averaging
>20 ns
h
Sync_X-Clock_X
>0 ns
As soon as a new line is selected, it has to be read out by the
output amplifiers. Before the pixels of the selected line can be
multiplexed onto the output amplifiers, one has to wait a
certain time, indicated as the ROT or Row overhead time
shown in Figure 15. This is the time to get the data stable from
the pixels to the output bus before the output stages. This ROT
is in fact lost time and rather critical in a high-speed sensor.
Different timings to reduce this ROT are explained in next
paragraph.
Please note that the pixel rate is the double frequency of the
Clock_x frequency. To obtain a pixel rate of 66 MHz, one needs
to apply a pixel clock Clock_x of 33MHz. When only 1 analog
output is used 2 pixels are output every Clock_x period. When
Clock_x is high, the first pixel is selected, when Clock_x is low,
the next pixel is selected. Consequently, during 1 complete
period of Clock_x 2 pixels are readout by the output amplifier.
If 2 analog outputs are used each Clock-X period 1 pixel is
presented at each output.
During the selection of 1 line, 2048 pixels are selected. These
2048 pixels have to be readout by 1 (or 2) output amplifier.
Document Number: 38-05712 Rev. *B
Page 19 of 38
LUPA-4000
Figure 16. X-addressing. From bottom to top: Clock_x, Sync_x, internal selection pixel 1&2, internal selection pixel 3&4,
internal selection pixel 5 & 6
The first pixel that is selected is the x-address downloaded in
the SPI. The starting address is the number downloaded into
the SPI, multiplied with 2.
Windowing is achieved by a starting address downloaded in
the SPI and the size of the window. In the x-direction, the size
is determined by the moment a new Clock_y is given. In the
y-direction, the sync_y pulse determines the size. Conse-
Document Number: 38-05712 Rev. *B
quently, the best way to obtain a certain window is by using an
internal counter in the controller.
Figure 16 is the simulation result after extraction of the layout
module from a different sensor to show the principle. In this
figure the pixel clock has a frequency of 50 MHz, which would
result in a pixel rate of 100 Msamples/sec.
Figure shows the relation between the applied Clock_x and
the output signal.
Page 20 of 38
LUPA-4000
Figure 17. Output signal related to Clock_x signal. From bottom to top: Clock_x, Sync_x and output. The output level
before the first pixel is the level of the last pixel of previous line
Pixel 1
Pixel2….: Pixel period : 20nsec
saturated
Output 1
dark
Sync_x
Clock_x:
25MHz
As soon as Sync_x is high and 1 rising edge of Clock_x occurs,
the pixels are brought to the analog outputs. This is again the
simulation result of a comparable sensor to show the principle.
Please note there is a time difference between the clock edge
and the moment the data is seen at the output. As this time
difference is very difficult to predict in advance, it is advisable
to have the ADC sampling clock flexible to set an optimal Add
sampling point. The time differences can easily vary between
5 - 15 nsec and have to be tested on the real devices.
Document Number: 38-05712 Rev. *B
Reduced Row Overhead Time timing
The row overhead time is the time between the selection of
lines that one has to wait to get the data stable at the column
amplifiers.
This row overhead time is a loss in time, which should be
reduced as much as possible.
Page 21 of 38
LUPA-4000
Standard timing (200 ns)
Figure 18. Standard timing for the R.O.T. Only pre_col and Norowsel control signals are required
In this case the control signals Norowsel and pre_col are made
active for about 20 nsec from the moment the next line is
selected. The time these pulses have to be active is related
with the biasing resistance Pre_load. The lower this
resistance, the shorter the pulse duration of Norowsel and
pre_col may be. After these pulses are given, one has to wait
for at least 180 nsec before the first pixels can be sampled. For
this mode Sh_col must be made active (low) all the time.
Back-up timing (ROT =100-200 ns)
A straightforward way of reducing the R.O.T is by using a
sample and hold function.
By means of Sh_col the analog data is tracked during the first
100 nsec during the selection of a new set of lines. After 100
nsec, the analog data is stored. The ROT is in this case
reduced to 100 nsec, but as the internal data was not stable
yet dynamic range is lost because not the complete analog
levels are reached yet after 100 ns.
Figure 18 shows this principle. Sh_col is now a pulse of 100
ns-200 ns starting at the same moment as pre_col and
Norowsel. The duration of Sh_col is equal to the ROT. The
shorter this time the shorter the ROT will be however this
lowers also the dynamic range.
In case "voltage averaging" is required, the sensor must work
in this mode with Sh_col signal and a "voltage averaging"
signal must be generated after Sh_col drops and before the
readout starts (see Figure 15)
Figure 19. Reduced standard ROT by means of Sh_col signal. pre_col (short pulse), Norowsel (short pulse) and Sh_col
(large pulse)
Precharging of the buses
This timing mode is exactly the same as the mode without
sample and hold, except that the prebus1 and prebus2 signals
are activated. It should be noticed that the precharging of the
buses can be combined with all of the timing modes discussed
Document Number: 38-05712 Rev. *B
above. The idea is to have a short pulse of about 5 ns to
precharge the output buses to a well-known level. This mode
makes the ghosting of bad columns impossible.
In this mode, Nsf_load must be made much larger (at least 1
Mohms).
Page 22 of 38
LUPA-4000
Figure 20. X- and Y-addressing with precharging of the buses
Table 14. Read-out timing specifications with precharching of the buses
Symbol
Name
Value
a
Sync_Y
>20 ns
b
Sync_Y-Clock_Y
>0 ns
c
Clock_Y-Sync_Y
>0 ns
d
NoRowSel
>50 ns
e
Pre_col
>50 ns
f
Sh_col
200 ns (or cst low, depending
on timing mode)
g
Voltage averaging
>20 ns
h
Sync_X-Clock_X
>0 ns
i
Prebus pulse
As short as possible
Document Number: 38-05712 Rev. *B
Page 23 of 38
LUPA-4000
Serial-Parallel-Interface (SPI)
The SPI is required to upload the different modes. Table 15
shows the parameters and there bit position
Table 15. SPI parameters
Parameter
Y-direction
Bit nr.
Remarks
0
1: from bottom to top
Y-address
1-10
Bit 1 is LSB
X-voltage averaging enable
11
1: Enabled
X-subsampling
12
1: Subsampling
X-direction
13
0: From left to right
X-address
14-23
Bit 14 is LSB
Nr output amplifiers
24
0: 1 Output
DAC
25-31
Bit 25 is LSB
When all zeros are loaded into the SPI, the sensor will start at
pixel 0,0. The scanning will be from left to right and from top to
bottom. There will be no sub-sampling or voltage averaging
and only one output is used. The DAC will have the lowest
level at its output.
When using sub sampling, only even X-addresses may be
applied.
Figure 21. SPI block diagram and timing
To sensor
D
Load_addr
Q
32 outputs to sensor
Bit 31
spi_in
Clock_spi
C
Entire uploadable block
Load_addr
Spi_in
Clock_spi
Bit 0
D
Q
C
Unity Ce ll
Clock_spi
spi_in
Load_addr
Document Number: 38-05712 Rev. *B
B0
B1
B2
B31
command
applied to
sensor
Page 24 of 38
LUPA-4000
Pin list
Table 16 is a list of all the pins and their functionalities.
Pad
1
Pin
E1
Pin Name
sync_x
Pin Type
Description
Input
Digital input. Synchronises the X-address register.
2
F1
eos_x
Testpin
Indicates when the end of the line is reached.
3
D2
vdd
Supply
Power supply digital modules.
4
G2
clock_x
Input
Digital input. Determines the pixel rate.
5
G1
eos_spi
Testpin
Checks if the data is transferred correctly through the SPI.
6
F2
spi_data
Input
Digital input. Data for the SPI.
7
H1
spi_load
Input
Digital input. Loads data into the SPI.
8
H2
spi_clock
Input
Digital input. Clock for the SPI.
9
J2
gndo
Ground
Ground output stages
10
J1
out2
Output
Analog output 2.
11
K1
out2DC
Output
Reference output 2.
12
M2
voo
Supply
Power supply output stages
13
L1
out1DC
Output
Reference output 1.
14
M1
out1
Output
Analog output 1.
15
N2
gndo
Ground
Ground output stages.
16
P1
vaa
Supply
Power supply analog modules.
17
P2
gnda
Ground
Ground analog modules.
18
N1
va3
Supply
Power supply column modules.
19
P3
vpix
Supply
Power supply pixel array.
20
Q1
psf_load
Input
Analog reference input. Biasing for column modules. Connect with R=1MΩ
to Vaa and decouple with C=100nF to gnda.
21
Q2
nsf_load
Input
Analog reference input. Biasing for column modules. Connect with R=5kΩ to
Vaa and decouple with C=100nF to gnda.
22
R1
muxbus_load
Input
Analog reference input. Biasing for multiplex bus. Connect with R=25kΩ to
Vaa and decouple with C=100nF to gnda.
23
R2
uni_load_fast
Input
Analog reference input. Biasing for column modules. Connect with R=10kΩ
to Vaa and decouple with C=100nF to gnda.
24
Q3
pre_load
Input
Analog reference input. Biasing for column modules. Connect with R=3kΩ to
Vaa and decouple with C=100nF to gnda.
25
Q4
out_load
Input
Analog reference input. Biasing for output stage. Connect with R=60kΩ to
Vaa and decouple with C=100nF to gnda.
26
N3
dec_x_load
Input
Analog reference input. Biasing for X-addressing. Connect with R=2MΩ to
Vdd and decouple with C=100nF to gndd.
27
Q5
uni_load
Input
Analog reference input. Biasing for column modules. Connect with R=1MΩ
to Vaa and decouple with C=100nF to gnda.
28
Q6
col_load
Input
Analog reference input. Biasing for column modules. Connect with R=1MΩ
to Vaa and decouple with C=100nF to gnda.
29
Q7
dec_y_load
Input
Analog reference input. Biasing for Y-addressing. Connect with R=2MΩ to
Vdd and decouple with C=100nF to gndd.
30
R3
vdd
Supply
Power supply digital modules.
31
M3
gndd
Ground
Ground digital modules.
32
L2
prebus1
Input
Digital input. Control signal to reduce readout time.
33
L3
prebus2
Input
Digital input. Control signal to reduce readout time.
Document Number: 38-05712 Rev. *B
Page 25 of 38
LUPA-4000
Pad
Pin
Pin Name
Pin Type
Description
34
Q8
sh_col
Input
Digital input. Control signal of the column readout.
35
R4
pre_col
Input
Digital input. Control signal of the column readout to reduce row-blanking
time.
36
R5
norowsel
Input
Digital input. Control signal of the column readout.
37
R6
clock_y
Input
Digital input. Clock of the Y-addressing.
38
R7
sync_y
Input
Digital input. Synchronises the Y-address register.
39
K2
eos_y_r
Testpin
Indicates when the end of frame is reached when scanning in the 'right'
direction.
40
Q9
temp_diode_p
Testpin
Anode of temperature diode.
41
Q10
temp_diode_n
Testpin
Cathode of temperature diode.
42
R8
vpix
Supply
Power supply pixel array.
43
R9
vmem_l
Supply
Power supply Vmem drivers.
44
R10
vmem_h
Supply
Power supply Vmem drivers.
45
R11
vres
Supply
Power supply reset drivers.
46
Q11
vres_ds
Supply
Power supply reset drivers.
47
R12
ref_low
Input
Analog reference input. Low reference voltage of ADC. (see Figure 7 for
exact resistor value)
48
Q12
linear_conv
Input
Digital input. 0= linear conversion; 1= gamma correction.
49
P15
bit_9
Output
Digital output 1 <9> (MSB).
50
Q14
bit_8
Output
Digital output 1 <8>.
51
Q15
bit_7
Output
Digital output 1 <7>.
52
R13
bit_6
Output
Digital output 1 <6>.
53
R14
bit_5
Output
Digital output 1 <5>.
54
R15
bit_4
Output
Digital output 1 <4>.
55
P14
bit_3
Output
Digital output 1 <3>.
56
Q13
bit_2
Output
Digital output 1 <2>.
57
R16
bit_1
Output
Digital output 1 <1>.
58
Q16
bit_0
Output
Digital output 1 <0> (LSB).
59
P16
clock
Input
ADC clock input.
60
N14
gndd
Supply
Digital GND of ADC circuitry.
61
N15
vddd
Supply
Digital supply of ADC circuitry (nominal 2.5V).
62
L16
gnda
Supply
Analog GND of ADC circuitry.
63
L15
vdda
Supply
Analog supply of ADC circuitry (nominal 2.5V).
64
N16
bit_inv
Input
Digital input. 0=no inversion of output bits; 1 = inversion of output bits.
65
M16
CMD_SS
Input
Analog reference input. Biasing of second stage of ADC. Connect to VDDA
with R=50 kΩ and decouple with C=100 nF to GNDa.
66
L14
analog_in
Input
Analog input of 1st ADC.
67
M15
CMD_FS
Input
Analog reference input. Biasing of first stage of ADC. Connect to VDDA with
R=50 kΩand decouple with C=100 nF to GNDa.
68
M14
ref_high
Input
Analog reference input. High reference voltage of ADC.
(see Figure 7 for exact resistor value)
69
K14
vres_ds
Supply
Power supply reset drivers.
70
J14
vres
Supply
Power supply reset drivers.
71
J15
vpre_l
Supply
Power supply precharge drivers. Must be able to sink current. Can also be
connected to ground.
72
J16
vdd
Supply
Power supply digital modules.
Document Number: 38-05712 Rev. *B
Page 26 of 38
LUPA-4000
Pad
Pin
Pin Name
Pin Type
Description
73
K15
vmem_h
Supply
Power supply Vmem drivers.
74
K16
vmem_l
Supply
Power supply Vmem drivers.
75
H15
ref_low
Input
Analog reference input. Low reference voltage of ADC.
(see Figure 7 for exact resistor value)
76
H16
linear_conv
Input
Digital input. 0= linear conversion; 1= gamma correction.
77
G16
bit_9
Output
Digital output 2 <9> (MSB).
78
F16
bit_8
Output
Digital output 2 <8>.
79
E16
bit_7
Output
Digital output 2 <7>.
80
G15
bit_6
Output
Digital output 2 <6>.
81
G14
bit_5
Output
Digital output 2 <5>.
82
F14
bit_4
Output
Digital output 2 <4>.
83
E14
bit_3
Output
Digital output 2 <3>.
84
D16
bit_2
Output
Digital output 2 <2>.
85
E15
bit_1
Output
Digital output 2 <1>.
86
F15
bit_0
Output
Digital output 2 <0> (LSB).
87
D15
clock
Input
ADC clock input.
88
C15
gndd
Supply
Digital GND of ADC circuitry.
89
D14
vddd
Supply
Digital supply of ADC circuitry (nominal 2.5V).
90
B16
gnda
Supply
Analog GND of ADC circuitry.
91
B14
vdda
Supply
Analog supply of ADC circuitry (nominal 2.5V).
92
C16
bit_inv
Input
Digital input. 0=no inversion of output bits; 1 = inversion of output bits.
93
A16
CMD_SS
Input
Biasing of second stage of ADC. Connect to VDDA with R=50 kΩ and
decouple with C=100 nF to GNDa.
94
B15
analog_in
Input
Analog input 2nd ADC.
95
A15
CMD_FS
Input
Analog reference input. Biasing of first stage of ADC. Connect to VDDA with
R=50 kΩ and decouple with C=100 nF to GNDa.
96
A14
ref_high
Input
Analog reference input. High reference voltage of ADC.
(see Figure 7 for exact resistor value)
97
C14
vres_ds
Supply
Power supply reset drivers.
98
B13
vres
Supply
Power supply reset drivers.
99
A13
vmem_h
Supply
Power supply Vmem drivers.
100
A9
vmem_l
Supply
Power supply Vmem drivers.
101
A10
vpix
Supply
Power supply pixel array.
102
A11
reset
Input
Digital input. Control of reset signal in the pixel.
103
A12
reset_ds
Input
Digital input. Control of double slope reset in the pixel.
104
B7
mem_hl
Input
Digital input. Control of Vmem signal in pixel.
105
B8
precharge
Input
Digital input. Control of Vprecharge signal in pixel.
106
B9
sample
Input
Digital input. Control of Vsample signal in pixel.
107
B10
temp_diode_n
Testpin
Cathode of temperature diode.
108
B11
temp_diode_p
Testpin
Anode of temperature diode.
109
B6
precharge_bias
Input
Analog reference input. Biasing for pixel array. (seeTable 10 for exact resistor
and capacitor value)
110
A8
photodiode
Testpin
Output photodiode.
111
A7
gndd
Ground
Ground digital modules.
112
B12
vdd
Supply
Power supply digital modules.
Document Number: 38-05712 Rev. *B
Page 27 of 38
LUPA-4000
Pad
Pin
Pin Name
Pin Type
Description
113
A6
eos_y_l
Testpin
Indicates when the end of frame is reached when scanning in the 'left'
direction.
114
A1
sync_y
Input
Digital input. Synchronises the Y-address register.
115
A5
clock_y
Input
Digital input. Clock of the Y-addressing.
116
A2
norowsel
Input
Digital input. Control signal of the column readout.
117
A3
volt. averaging
Input
Digital input. Control signal of the voltage averaging in the column readout.
118
B5
pre_col
Input
Digital input. Control signal of the column readout to reduce row-blanking
time.
119
A4
sh_col
Input
Digital input. Control signal of the column readout.
120
B1
prebus2
Input
Digital input. Control signal to reduce readout time.
121
B2
prebus1
Input
Digital input. Control signal to reduce readout time.
122
C1
dec_y_load
Input
Analog reference input. Biasing for Y-addressing.
123
D1
vpix
Supply
Power supply pixel array.
124
B4
va3
Supply
Power supply column modules.
125
B3
gnda
Ground
Ground analog modules.
126
C2
vaa
Supply
Power supply analog modules.
127E2
E2
gndd
Ground
Ground digital modules.
REMARKS:
1. All pins with the same name can be connected together.
2. All digital input are active high (unless mentioned
otherwise).
Document Number: 38-05712 Rev. *B
3. All unused inputs should be tied to a non-active level (e.g.
VDD or GND).
Page 28 of 38
LUPA-4000
Geometry and Mechanical specifications
Bare die
Figure 22. Die figure of the LUPA-4000
27200 M m
Pixel array of 2048 x 2048 pixels
Pixel 0,0
25610 Mm
Pixel 0,0 is located at 478 µm from the left side of the die and
1366 µm from the bottom side of the die.
Document Number: 38-05712 Rev. *B
Page 29 of 38
LUPA-4000
Package drawing
The LUPA-4000 is packaged in a 127-pin PGA package.
Figure 23. Package drawing of the LUPA-4000 package
Document Number: 38-05712 Rev. *B
Page 30 of 38
LUPA-4000
Figure 24. LUPA-4000 package specifications with die
Document Number: 38-05712 Rev. *B
Page 31 of 38
LUPA-4000
Bonding pads
The bonding pads are located as indicated below.
Figure 25. Placing of the bonding pads on the LUPA-4000 package
Document Number: 38-05712 Rev. *B
Page 32 of 38
LUPA-4000
Bonding diagram
The die is bonded to the bonding pads of the package as
indicated below
Figure 26. Bonding pads diagram of the LUPA-4000 package.
The die will be placed in the package in a way that the center
of the light sensitive area will match the center of the package.
Document Number: 38-05712 Rev. *B
Page 33 of 38
LUPA-4000
Glass transmittance
A D263 glass will be used as protection glass lid on top of the
LUPA-4000 monochrome sensors. Figure 24 shows the transmission characteristics of the D263 glass
Figure 27. Transmission characteristics of the D263 glass used as protective cover for the LUPA-4000 sensors
100
Transmission [%]
90
80
70
60
50
40
30
20
10
0
400
500
600
700
800
900
Wavelength [nm ]
Document Number: 38-05712 Rev. *B
Page 34 of 38
LUPA-4000
Handling and soldering precautions
Special care should be given when soldering image sensors
with color filter arrays (RGB color filters), onto a circuit board,
since color filters are sensitive to high temperatures.
Prolonged heating at elevated temperatures may result in
deterioration of the performance of the sensor. The following
recommendations are made to ensure that sensor performance is not compromised during end-users' assembly
processes.
Board Assembly:
Precautions and cleaning:
Avoid spilling solder flux on the cover glass; bare glass and
particularly glass with antireflection filters may be adversely
affected by the flux. Avoid mechanical or particulate damage
to the cover glass.
It is recommended that isopropyl alcohol (IPA) is used as a
solvent for cleaning the image sensor glass lid. When using
other solvents, it should be confirmed beforehand whether the
solvent will dissolve the package and/or the glass lid or not.
Device placement onto boards should be done in accordance
with strict ESD controls for Class 0, JESD22 Human Body
Model, and Class A, JESD22 Machine Model devices.
Assembly operators should always wear all designated and
approved grounding equipment; grounded wrist straps at ESD
protected workstations are recommended including the use of
ionized blowers. All tools should be ESD protected.
Ordering Information
Manual Soldering:
The LUPA-4000 is only to be used for non-military
applications. A strict exclusivity agreement prevents us to sell
the LUPA-4000 to customers who intend to use it for military
applications.
When a soldering iron is used the following conditions should
be observed:
• Use a soldering iron with temperature control at the tip.
• The soldering iron tip temperature should not exceed
350°C.
• The soldering period for each pin should be less than 5
seconds.
Document Number: 38-05712 Rev. *B
FillFactory Part Number
Cypress Semiconductor
Part Number
LUPA-4000-M
CYIL1SM4000AA-GBC
Disclaimer
FillFactory image sensors are only warranted to meet the
specifications as described in the production data sheet.
Specifications are subject to change without notice.
Please contact info@FillFactory.com for more information.
Page 35 of 38
LUPA-4000
APPENDIX A: LUPA-4000 evaluation system
For evaluating purposes an LUPA-4000 evaluation kit is
available.
The LUPA-4000 evaluation kit consists of a multifunctional
digital board (memory, sequencer and IEEE 1394 Fire Wire
interface) and an analog image sensor board.
Visual Basic software (under Win 2000 or XP) allows the
grabbing and display of images and movies from the sensor.
All acquired images and movies can be stored in different file
formats (8 or 16-bit). All setting can be adjusted on the fly to
evaluate the sensors specs. Default register values can be
loaded to start the software in a desired state
Figure 28. Content of the LUPA-4000 evaluation kit
Please contact Fillfactory (info@Fillfactory.com) if you want
any more information on the evaluation kit.
Document Number: 38-05712 Rev. *B
Page 36 of 38
LUPA-4000
APPENDIX B: Frequently Asked Questions
Q: How does the dual (multiple) slope extended dynamic range mode works?
A:
Figure 29. Dual slope diagram
Reset pulse
Read out
Double slope reset pulse
Reset level 1
p1
Reset level 2
p2
p3
p4
Saturation level
Double slope reset time (usually 510% of the total integration time)
Total integration time
The green lines are the analog signal on the photodiode, which decrease as a result of exposure. The slope is determined by the
amount of light at each pixel (the more light the steeper the slope). When the pixels reach the saturation level the analog signal
will not change despite further exposure. As you can see without any double slope pulse pixels p3 and p4 will reach saturation
before the sample moment of the analog values, no signal will be acquired without double slope. When double slope is enabled
a second reset pulse will be given (blue line) at a certain time before the end of the integration time. This double slope reset pulse
resets the analog signal of the pixels BELOW this level to the reset level. After the reset the analog signal starts to decrease with
the same slope as before the double slope reset pulse. If the double slope reset pulse is placed at the end of the integration time
(90% for instance) the analog signal that would have reach the saturation levels aren't saturated anymore (this increases the
optical dynamic range) at read out. It's important to notice that pixel signals above the double slope reset level will not be
influenced by this double slope reset pulse (p1 and p2).
All products and company names mentioned in this document may be the trademarks of their respective holders.
Document Number: 38-05712 Rev. *B
Page 37 of 38
© Cypress Semiconductor Corporation, 2006. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use
of any circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be
used for medical, life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cypress does not authorize its
products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress
products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges.
LUPA-4000
Document History Page
Document Title: LUPA-4000 4M PIXEL CMOS Image Sensor
Document Number: 38-05712
REV.
ECN.
Issue Date
Orig. of
Change
Description of Change
**
310396
See ECN
FPW
Initial Cypress Release
*A
497132
See ECN
QGS
Converted to Frame file
*B
649219
See ECN
FPW
Ordering information update+ title update + package spec label
Document Number: 38-05712 Rev. *B
Page 38 of 38