HSMS-2812 Datasheet, PDF (3/10 Pages) AVAGO TECHNOLOGIES LIMITED – Surface Mount RF Schottky Barrier Diodes

Quad Capacitance
Capacitance of Schottky diode quads is measured using
an HP4271 LCR meter. This instrument effectively isolates
individual diode branches from the others, allowing ac‑
curate capacitance measurement of each branch or each
diode. The conditions are: 20 mV R.M.S. voltage at 1 MHz.
Avago defines this measurement as “CM”, and it is equiva‑
lent to the capaci­tance of the diode by itself. The equiva‑
lent diagonal and adja­cent capaci-tances can then be cal‑
culated by the formulas given below.
In a quad, the diagonal capaci­tance is the capacitance be‑
tween points A and B as shown in the figure below. The
diagonal capacitance is calculated using the following
formula
C _DIAGONAL = _C_¹_x__C_²_ + _C__³_x_C__⁴
C₁ + C₂ C₃ + C₄
Tbheetwe_CeqeDAun_IDAi_JGv_ApOa_CoNEle_NiAnnTLtts==aAd_{_CCa_}ja_{11n_}c_{x+_de_C}n_{_C__}t_{2__inc+_}a_{_tp_h_}a_{C_e_}c_{_13_}if_{_}ti_{_x}ag_{__C}n_{_u_}c_{_r_4ee}
is the
below.
capacitance
This capaci‑
tance is calculated^Cu¹s⁺in^Cg²t_–h^1–e₊f^Co_–l¹³l_–o⁺w_+Ci_–n¹⁴_–g formula
C _ADJACENT = C ₁ + ___C_²___C1__³__C_ ⁴
R_j=
8.33
I
b^{X+10–CI1}s^–_2-^{+5 n–1CT–}₃⁺
1
––
C₄
This information
odes.
R_j=
does not
8.33 X 10
I _b+I_s
a_-5p_np_Tly
to
cross-over
quad
di‑
Linear Equivalent Circuit Model Diode Chip
R_j
R_S
C_j
R_S = series resistance (see Table of SPICE parameters)
C _j = junction capacitance (see Table of SPICE parameters)
R_j =
8.33 X 10^-5 nT
I_b + I_s
where
I_b = externally applied bias current in amps
I_s = saturation current (see table of SPICE parameters)
T = temperature, °K
n = ideality factor (see table of SPICE parameters)
Note:
To effectively model the packaged HSMS-281x product,
please refer to Application Note AN1124.
ESD WARNING:
Handling Precautions Should Be Taken To Avoid Static Discharge.
SPICE Parameters
Parameter Units
B_V
V
C_J0
pF
E_G
eV
I_BV
A
I_S
A
N
R_S
Ω
P_B
V
P_T
M
HSMS-281x
25
1.1
0.69
E-5
4.8E-9
1.08
10
0.65
2
0.5