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Simulation Input and Output Requirements

The following input and output requirements for each simulation type are also required for the corresponding measurement types.

DC Simulation

The following table describes the input and output specifications required for a valid setup for DC simulation and the following figure shows an example of input and output specifications for a MOSFET id versus vg setup.

Table 12 Input and Output Requirements for a DC Simulation
INPUT MODE
VALID SWEEPS
VALID OUTPUTS
V
 LIN, LOG, LIST, SYNC, CON
 V, I
I
 LIN, LOG, LIST, SYNC, CON
 V, I

Figure 13 Example Input and Output, DC Simulation

AC Simulation

The following table describes the input and output specifications required for a valid setup for AC simulation. The following figure shows an example of input and output specifications for simulating the output voltage versus frequency of an inverting operational amplifier.

Table 13 Input and Output Requirements for an AC Simulation 
INPUT MODE
VALID SWEEPS
VALID OUTPUTS
COMMENTS
V
 LIN, LOG, LIST, SYNC, CON, AC
 V, I
 1. Exactly one frequency sweep required.
I
 LIN, LOG, LIST, SYNC, CON, AC
 V, I
 2. At least one AC source required.
F
 LIN, LOG, LIST, CON
 V, I
 3. SYNC is not a valid sweep type when using ADS simulators.

Figure 14 Example Input and Output, AC Simulation

Transient Simulation

The following table describes the input and output specifications required for a valid setup for Transient simulation and the following figure shows an example of input and output specifications for voltage versus time characteristics of a differential pair.

Table 14 Input and Output Requirements for a Transient Simulation
INPUT MODE
VALID SWEEPS
VALID OUTPUTS
COMMENTS
T
 LIN, LIST, CON
 V, I
 1. Exactly one time sweep required
V
 LIN, LOG, LIST, SYNC, CON, EXP, PULSE, PWL, SFFM, SIN
 V, I
 2. LIST sweep not supported with Saber
I
 LIN, LOG, LIST, SYNC, CON, EXP, PULSE, PWL, SFFM, SIN
 V, I

Figure 15 Example Input and Output, Transient Simulation

Noise Simulation

The following tables describe the input and output specifications required for a valid setup for Noise simulation depending on the simulator being used.

Table 15 Input and Output Requirements for a Noise Simulation using SPICE Simulators 
INPUT MODE
VALID SWEEPS
VALID OUTPUTS
COMMENTS
V
 LIN, LOG, LIST, SYNC, CON, AC
 N
 1. Exactly one noise output required.
I
 LIN, LOG, LIST, SYNC, CON, AC
 N
 2. Exactly one frequency sweep required.
F
 LIN, LOG, CON
 N
 3. At least one AC source required.

Table 16 Input and Output Requirements for a Noise Simulation using ADS Simulators
INPUT MODE
VALID SWEEPS
VALID OUTPUTS
COMMENTS
V
 LIN, LOG, LIST, SYNC, CON, AC
 N, V, I
 1. There can be multiple outputs.
I
 LIN, LOG, LIST, SYNC, CON, AC
 N, V, I
 2. Exactly one frequency sweep required.
F
 LIN, LOG, SEG, CON
 N, V, I
 3. Both V and I Outputs are DC outputs.

CV Simulation

The following table describes the input and output specifications required for a valid setup for CV simulation and the following figure shows an example of input and output specifications for a BJT base-emitter pn-junction capacitance versus voltage setup.

Note


The frequency at which the CV simulation is performed can be specified using the System Variable CV_FREQ in Hz. If this variable is not specified, the simulation will be performed at 1-MG (Hz).

Table 17 Input and Output Requirements for a CV Simulation
INPUT MODE
VALID SWEEPS
VALID OUTPUTS
COMMENTS
V
 LIN, LOG, LIST, SYNC, CON
 a single C, a single G, a single R, a single X, C + G, C + R
 1. Any single output type of C, G, R, or X; or exactly one C and one G; or exactly one C and one R.
I
 LIN, LOG, LIST, SYNC, CON
 a single C, a single G, a single R, a single X, C + G, C + R
 2. A single C or a C + G is the capacitance using Cp-Gp mode, while a C + R will simulate Cs-Rs data

Figure 16 Example Input and Output, CV Simulation

2-Port Simulation

The following table describes the input and output specifications required for a valid setup for 2-port simulation and the following figure shows an example of input and output specifications for an H21-parameter versus Vbe setup.

Table 18 Input and Output Requirements for a 2-Port Simulation
INPUT MODE
VALID SWEEPS
VALID OUTPUTS
COMMENTS
F
 LIN, LOG, LIST, CON
 S, H, Y, Z, K, A, F
 1. Exactly one frequency sweep required.
V
 LIN, LOG, LIST, SYNC, CON
 S, H, Y, Z, K, A, F
 2. Exactly one 2-port output (S,H,Y,Z,K or A) required.
I
 LIN, LOG, LIST, SYNC, CON
 S, H, Y, Z, K, A, F
 3. Only ADS supports F output.1






4. Exactly one 2-port output required for F output.






5. F output can be multiple outputs.
12-Port noise simulation supports ADS only. If the SIMULATOR is not equal to hpeesofsim, the following error message appears.
Error: in "Output xxxx"
High frequency noise output is not supported with current simulator.

Table 19 High Frequency Noise Output and Its Data Type Description
F Output
Name (Output Editor)
Symbol shown on Setup Page
Description
Port Input Requirement
Mode
 High Frequency Noise
 F
 High frequency noise mode type

Data Type
 Noise Figure
 NF
 Noise figure data
 Yes1, 2


Gamma Opt
 GAMMAOPT
 Optimum source reflection coefficients
 No


Equivalent R Noise
 RN
 Equivalent noise resistance data
 No


Min Noise Figure
 NFMIN
 Minimum noise figure data
 No


Equivalent Noise Temperature
 TE
 Equivalent Noise Temperature data
 Yes *, †
1The port field of the NF/TE noise parameter can not be blank.
If the port field set NF/TE type is blank, the following error message appears.
Error: in "Output xxxx"
Blank output node name for NF specified.
 2The port name of the NF/TE parameter must be consistent with the port name of the 2-port output.
The port name of the NF/TE output noise must be equal to one of the port names of the 2-port output; otherwise, the following error message appears.
Error: in "Output xxxx"
Port "xx" is not consistent with the 2-port specification node: "xx" or "xx"

Figure 17 Example Input and Output, 2-Port Simulation

Active Setup: /bjt_ncehf/sp/sparm_noise_bias

Figure 18 Example Input and Output, 2-Port Noise Simulation

2-Port Circuits

An L-network of LCR is added to port 1 and port 2 to uncouple an AC signal from a DC bias to simulate a DUT using AC analysis. To see an actual input circuit deck, use the Simulator Debugger.

When the port 1 has an AC source, its signal goes through an R whose value is defined by TWOPORT_Z0 and its default is 50 [ohm]. Then this signal is given to a port 1 through a C whose value is defined by TWOPORT_C, and its default is 100 [F]. The port 1 is also connected to a DC bias source through an L whose value is defined by TWOPORT_L and its default is 100 [H]. The port 2 has a similar L-network whose AC source is replaced by a short to ground.

Note


Because the default C and L values are so large compared to actual DUT values, sometimes it is necessary to specify smaller values to reduce numeric errors in simulation. For example, 1mF for C and 1mH for L are more realistic values.

There are two circuits in a single deck to represent two cases where the port 1 has a source and the port 2 has a source. These circuits are generated and added to a DUT for simulators.

TDR Simulation

The following table describes the input and output specifications required for a valid setup for TDR (Time Domain Reflect) simulation. The following figure shows an example of input and output specifications for simulating the reflected and transmitted signal of a simple TDR circuit.

Table 20 Input and Output Requirements for a TDR Simulation
INPUT MODE
VALID SWEEPS
VALID OUTPUTS
COMMENTS
T
 LIN, LIST, CON
 V
 1. Exactly one time sweep required.
V
 LIN, LOG,L IST, SYNC, CON, TDR
 V
 2. Only voltage outputs allowed.
I
 LIN, LOG, LIST, SYNC, CON
 V
 3. Exactly one voltage sweep of type TDR required.

Figure 19 Example of Input and Output Specifications for a TDR Simulation

Harmonic Balance Simulation

The following table describes the input and output specifications required for a valid setup for Harmonic Balance simulation and the following figure shows an example of input and output specifications for a BJT power-in versus power-out setup.

Table 21 Input and Output Requirements for a Harmonic Balance Simulation
INPUT MODE
VALID SWEEPS
VALID OUTPUTS
COMMENTS
V
 LIN, LOG, LIST, SYNC, CON, AC
 V, I
 1. Exactly one frequency sweep with Sweep Type = HB required.
I
 LIN, LOG, LIST, SYNC, CON, AC
 V, I
 2. At least one AC source required: V or I (AC), or W.
F
 HB
 V, I
 3. The Test Circuit includes elements such as DCFEED or DCBLOCK.
W (Power)
 LIN, LOG, LIST, CON
 V, I
 4, Units for the Power (W) source can be set to dBm(d) or Watts (W).

Figure 20 Example of Input and Output Specifications for a Harmonic Balance Simulation

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