A parameterized photodetector model which is statistically enabled. In this template, the performance metrics of the device (dark current, responsivity and bandwidth) are dependent on its physical dimensions (width and length) as well as bias voltage, temperature and frequency (wavelength) of light. In addition, these figures of merit support statistical variation for different temperatures.
For information on statistical CMLs, see Statistical CMLs.
Note: For legacy data format (2022 R2.4 and older) please visit following link:
Photodetector Pcell (Statistical) - Lumfoundry Template (Legacy)
Template: pd_pcell_stat_c
Photonic Model: photodetector_pcell
Quality Assurance Test: photodetector_pcell QA
Parameters: width, length, temperature
Statistically Enabled Parameters: responsivity, bandwidth, dark current.
Interoperability with Cadence Virtuoso:
- Circuit design flows using INTERCONNECT model: Yes.
- Circuit design flow using photonic Verilog-A model: Yes.
Modeling Data
The source data template for a photodetector pcell element can divided into two sections.
- For new users (continue with following section: Basic data requirement section)
- Advanced users ( continue with section: Complete Data Requirement )
The photodetector pcell template can be used to create a very advanced compact model for a custom photodetector pcell . The template contains a lot of different modeling data to create an accurate model. However, not all these data need to be updated by the user. The fastest/ simplest way to modify the template data and create a custom compact model would be to only update the values of the data listed in the 'basic data requirement section' below, while all rest of the data (which is illustrated in detail in subsequent sections) can be left at their default value.
Note: Advanced users please jump start with Complete Data Requirement (for advanced users) section.
Basic data requirement section (for new users)
The basic or minimum data required to build the photodetector pcell model is described below.
general
"general" is a struct with following fields:
Field | Type | Description |
---|---|---|
description | string | A string containing a brief description of the model, which will be displayed to the end user. |
notes | cell |
A cell array that provides model notes which will be displayed to the end user. Each element of the cell is a struct with the fields:
|
ports
"ports" is a struct with following fields:
Field | Type | Description |
---|---|---|
opt_1 |
struct with fields described in table below | Port definition corresponding to the input optical port |
ele_an |
Port definition corresponding to the anode and cathode of the photodetector. |
|
ele_cat |
Each struct above consists of following fields:
Field | Type | Description |
---|---|---|
name | string | The name of the port, which will be visible to the end user. This name should be consistent with the name that will be used for netlisting. |
dir | string | The directionality of the port, either "Input", "Output", or "Bidirectional" |
pos | string |
The side of the model which the port will be displayed on, either "Left", "Right", "Top", or "Bottom" |
order | number |
The order at which the port is listed in a netlist. |
parameters
"parameters" is a struct with following fields:
Field | Type | Description |
---|---|---|
temperature | struct with fields described in table below |
The temperature at which the models operate. Note:
|
thermal_noise |
The thermal noise of the photodetector. Note:
|
length | struct with fields described in table below |
Parameter defining the length (m) of the photodetector. |
width |
Parameter defining the width (m) of the photodetector. |
Each struct above consists of following fields:
Field | Type | Description |
---|---|---|
name |
string |
The name for display in the Property View window. |
default |
number |
The nominal value of the parameter in SI unit. |
unit |
string |
The default unit for display in the Property View window. |
min
|
number |
Minimum allowed value if the visible_to_user is set to True. |
max
|
number |
Maximum allowed value if the visible_to_user is set to True. |
model_data
"model_data" is a struct with following fields:
Field | Type | Description |
---|---|---|
mode_data |
cell |
M x 1 cell array, where M is the number of modes. Each element of the cell is a struct with fields:
Note: This model only supports a up to two modes. |
bandwidth_data
|
struct
|
The 3-dB cutoff frequency data of the photodetector as a function of bias voltage, width, length, and temperature. The required fields are:
Note: Data must be provided for at least two data points for each parameter (V,W,L,T > 1) |
Idark_data
|
struct
|
The total dark current of the photodetector as a function of bias voltage, width, length, and temperature. The required fields are:
Note:
|
resp_data
|
struct |
The responsivity of the photodetector as a function of frequency, bias voltage, width, length, and temperature. The required fields are:
Notes:
|
Complete data requirement (for advanced users)
The complete data section provides a complete reference of data supported by the photodetector pcell model including the basic required data described in the previous section. The description of all the fields in the photodetector pcell source data template are described below.
general
"general" is a struct with following fields:
[[snippet||11549514081811]]
ports
"ports" is a struct with following fields:
[[snippet||12153503240467]]
opt_2 (optional) |
struct with fields described in table below |
Port definition corresponding to the second input optical port |
ele_an_2 (optional) |
Port definition corresponding to the second anode of the photodetector. |
Each struct above consists of following fields:
[[snippet||11549759363603]]
parameters
"parameters" is a struct with following fields:
[[snippet||12153804332691]]
length | struct with fields described in table below |
Parameter defining the length (m) of the photodetector. |
width |
Parameter defining the width (m) of the photodetector. |
Each struct above consists of following fields:
[[snippet||11720299494931]]
model_data
"model_data" is a struct with following fields:
[[snippet||12161931903123]]
QA
"QA" is a struct with following fields:
[[snippet||12155371687955]]
temperature | number |
Temperatures (K) at which all tests will be done (can be a single value or an array). |
length |
2x1 array containing the min/max values for width/length parameters (m) used during the QA tests. This is to reduce the range of values used during QA tests. |
|
width |
statistical
"statistical" is a struct with fields below. This struct is optional and is only required for statistical compact models.
Note: To allow CML Compiler to build statistically enabled models, the statistical_parameter_status has to be defined in the XML file. For more information, see Statistical CMLs.
Field | Type | Description |
---|---|---|
parameters |
struct |
Each field of this struct defines one statistical parameter for the model. These fields should have names following "parameter_X" where X is an integer and follow the structure described in statistical parameters table. Note: This data is required for CML Compiler to enable statistical modeling. |
QA |
struct with fields described in QA table |
Defining QA settings for statistical QA. |
statistical parameters
[[snippet||11647965606547]]
slope_Resp |
number |
F x V x W x L x T matrix indicating the sensitivity of the responsivity of the photodetector with respect to the X-th statistical parameter defined as d_Resp / d_parameter_X as a function of:
Note:
|
slope_BW |
number |
V x W x L x T matrix indicating the sensitivity of the electro-optic bandwidth of the photodetector with respect to the X-th statistical parameter defined as d_BW / d_parameter_X as a function of:
Note:
|
slope_Idark |
number |
V x W x L x T matrix indicating the sensitivity of the dark current of the photodetector with respect to the X-th statistical parameter defined as d_Idark / parameter_X as a function of:
Note:
|
statistical QA
[[snippet||12156461004947]]
VA_reference_data_available
|
boolean | When true, Verilog-A statistical QA results will be compared against reference data of Verilog-A simulation. When false, reference data is generated (only needed for the first run or after a model update). |
VA_N_trials | number | Number of trials in Monte Carlo sweep for Verilog-A |
parameters | struct |
Parameter values used for setting up the QA test bench. The required fields are:
|