Download EV76C570 Multi Integration

EV76C570 Multi Integration
Rev.4 Nov 13 / VP
BRIEF DESCRIPTION
This mode allows using the multi integration functionality of the EV76C570.
Application Note
APPLICABLE PRODUCT
- EV76C570
EOS-AN028
KEYWORDS
Multi-Integration
Range-Gating
Active Imaging
1. DESCRIPTION
The EV76C570 can be used in a specific integration mode called Multi-Integration. The “classic” integration time is here
divided in several small integration times, controlled by the user. The sensor can receive an input signal on the Trig pin
corresponding to the “integration timing” needed.
The sensor, running in Global Shutter mode, can be used in:
-
Slave mode: the integration starts with the input signal and it controls the small integrations duration,
-
Master mode: the sensor is in free run with a programmed integration time and the input signal will be taken
into account only during the sensor defined integration time.
2. REGISTER SETTING
To use the Multi-Integration mode, the sensor needs to be initialized correctly using the dedicated application note. Then,
the registers to program are the following:
Table 1 : Registers for Multi-Integration mode
Bit Field
Bit
position
roi_readout_mode
roi_flash_mode
Address
Register Name
Value to program
Comments
0B h
reg_ctrl_cfg
5:4
11
activates the multi-integration mode
7:6
01
46 h
-
-
forced to FLO = Tint
47 h
-
-
0x076F
48 h
-
-
0xEFED
4E h
-
-
0x0000
0x4300
Analog adjustments
1/4
3. INPUT SIGNAL
When the sensor is correctly programmed, the input signal controls the multi-integration times period and duration. Each
pulse will set the pixel in integration state. It starts at the rising edge and stops at the falling edge (depending on the
programmed polarity). The signal is a 1.8V input.
Figure 1 : Input Signal limitation
P
W
Trig In Signal
The minimum pulse width (W) is 50ns.
The minimum pulse period (P) is 16µs.
3.1 SLAVE MODE
The Slave mode allows the Trig input starting and controlling the multi-integration mode.
Figure 2 : Input Signal limitation
Integration Time
FLO
Trig In Signal
starts
the acquisition
multiple integrations
By default, the sensor is in Idle mode. As shown on Figure 2, the first Trig pulse is used to start an acquisition
(integration time + readout), and the following ones are used to define the integration pulses. After the acquisition, the
sensor will come back in Idle mode. New Trig pulses will start again one acquisition in multi-integration mode.
After each pulse (the duration defines the small integration time), the electrons collected in the photodiode will be
transfered in the memory node. When all the pulses are done, the readout is done without any modification compared to
a standard Global Shutter readout.
The overall integration is controlled by registers 0x0E and 0x0F. To run as slave mode, the following programming needs
also to be done.
Table 2 : Registers for Slave mode
Address
Register Name
0B h
reg_ctrl_cfg
2/4
Bit Field
Bit position
Value to program
trig_rqst
1
0
trig_pad_sel
8
1
EOS-AN028
Rev.4 Nov 13 / VP
EOS-AN028
3.2 MASTER MODE
With the Master mode, the sensor is in free run and integration pulses will be taken into account during the integration
defined by the user (output on FLO). The following programming needs to be done:
Table 3 : Registers for Master mode
Address
0B h
Register Name
reg_ctrl_cfg
Bit Field
Bit position
trig_rqst
1
Value to program
1
trig_pad_sel
8
0
Figure 3 : Input Signal limitation
Integration Time (FLO output)
Δt
NOK
OK
OK
OK
NOK
Trig In Signal
4. USING THE DEMO BOARD
The Multi-Integration mode can be set up with the demo board. The easiest mode to use with the DK is the Slave mode.
4.1 SETTINGS
First, a solder drop (or a 0 ohm resistor) needs to be put in place of the R129, which is not populated by default. Then,
the user can inject the input signal on the pin 2 of the J11 (see Figure 4). The GUI will be useful to set the sensor in the
mode described above.
The J3 (above the J11) can also be used for Ground connection and for Flash Output synchronization.
The J3 pinout is:
1 : NC
2 : Flash Output (FLO)
3 : GND
5. APPLICATIONS
This function can be used for:
any multi-integration purpose,
Active Imaging / Range Gating.
3/4
Rev.4 Nov 13 / VP
Figure 4 : Demokit rear face with J11 connector and R129 resistor
4/4
EOS-AN028
Rev.4 Nov 13 / VP