C_RIND

	C_RIND Coplanar Rectangular Inductor Parameters Notes Equivalent Circuit
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Coplanar Rectangular Inductor

The C_IDC module represents a rectangular spiral inductor between two coplanar lines. WT is the width of turns, ST the distance between turns and S the distance to the ground planes. The dimensions of connected lines at ports are defined using data items addressed by C_ LTYP1 and C_LTYP2. The type and dimensions of the air-bridge as back track are defined by the airtype data item C_BTR. L1 and L2 are the length of coplanar lines connected at ports.

Parameters

Parameter	Description	Range of Usage
L1	Length of transmission line connected to the port 1
L2	Length of transmission line connected to the port 2
N	Number of turns (positive ® contra clock wise, negative ® clock wise)	\|N\|=1.5, 2.5, 3.5, ...
WT	Track width	n/2.DL(n=1,2,3,...)
ST	Slot between tracks	n/2.DL(n=2,3,4,...)
I_DIA1	Inner diameter 1 (I_DIA1 ³ ST)	n/2.DL(n=1,2,3,...)
I_DIA2	Inner diameter 2	n/2.DL(n=1,2,3,...)
S	Slot between track and ground	n/2.DL(n=1,2,3,...)
INDLEVEL	Identification of metal level of inductor turns	1 or 2 (DEFAULT Foundry)
C_LTYP1	ID of coplanar transmission line applied at ports 1
C_LTYP2	ID of coplanar transmission line applied at ports 2
C_SUB	ID of coplanar substrate definition
C_GRID	ID of simulation control data
TEMP	ID of element temperature definition used for noise computation

Notes

In the current version, the same C_LTYP is applied at both ports for the simulation (C_LTYP2 = C_LTYP1).
A negative value for L1 or L2 can be meaningful during the simulation. In such cases, the automated layout generation works incorrectly and the generated layout has to be edited manually. The minimum value for L1 and L2 depends on the metal layer oversize in the currently selected C_LAYER. In case of DEFAULT foundry, L1 and L2 should be greater than or equal to max(|cond_os|, |cond2_os|).
I_DIA1 must be greater than or equal ST. I_DIA2 must be greater than or equal to via_ol–WT.
The minimum value for N is 1.5 and the increment is 1. Negative value for N (-1.5, -2.5, -3.5 ...) indicates the turn direction in clock wise and positive value in contra clock wise (see Layout). The sign of N has no effect on simulation.
TYPE=0 and TYPE= –1 is not allowed in C_AIRTYP addressed by C_BTR.
The parameter INDLEVEL indicates the metal level used for the turns of the uinductor. The only valid value for this parameter in the DEFAULT foundry is 1 or 2. INDLEVEL and TYPE in C_AIRTYP addressed by C_BTR must be different.
If the length of connected line to port1 (L1) is less than via_ol, CEN_MET in C_LTYP1 must be the same as TYPE in C_BTR.

If L1 and L2 in selected C_GRID are not set to –1 or –2 (auto sizing), the minimum values for L1 and L2 are:

L1_min= max(WT+(WT+ST).(2N-1)-ST+IDIA1+2S+8DL, W1+2S1+2GW1,W2+2S2+2GW2)

L2_min=2WT+(WT+ST).(2N-1)+IDIA2+2S+8DL

Equivalent Circuit

For the modeling of the C_RIND element, a broadband network is used. Each segment (one turn is built of four segments) is represented by a p-network consisting of two capacitances Cp_i and Cp_i+1(parasitic electric fields of the segment to the ground), an inductance L_i(self inductance of the segment and the mutual inductance due to the magnetic coupling between the segments) and a frequency dependent resistance R_i(losses of the segment). The electrical coupling between theturns is represented by the capacitance Cs.

As a result of the broadband modelling, the traveling wave effects along the turns is taken into account. The equivalent circuit parameters are derived from quasi-static FD-calculations. The connected line at ports are modeled as C_LIN elements and are represented by their characteristic mpedances ZL1, ZL2 and phase constants b1, b2. There is no limitation due to the length of connected lines (L1 and L2).