Electronics Formula Sheet

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● Over drive Voltage: = ( βˆ’ ) ● β€² = (/ 2 ) ● Cut off ( =0): < ; ● Channel induced and Mosfet is in triode or saturation: = + Stats Triode region Saturation Region Conditions > < ≀ β‰₯ 1 2 β€² ( βˆ’ 1 2 ) 1 2 β€² 2 ● = = β€² = = √2 β€² √ √( ) = 2 (4.6.2,6), ● = 1 , ● = | | , ● = βˆ’ ( || ), Characteristic Parameters MOSFET Voltage Gain, Input Resistance, Output Resistance, Common Source (Hybrid model) βˆ’ ( || || ) βˆ’ + ( || || ) ∞ || Common Source with a source resistance (T-Model) βˆ’ ( || ) 1+ βˆ’ + ( || ) 1+ ∞ Common Gate (T-Model) ( || ) 1 1+ ( || ) 1 Common Drain (T-Model) || ( || )+ 1 + . || ( || )+ 1 ∞ 1 ● = 2( + ) (Unity Gain Frequency) ● β€² = || || ● = (1 + β€² ) ● = + , ● = 1 2 ( || ) (Upper 3-dB freq.) Differential and multi-stage amplifier Let I be the total current in common mode voltage ● 1 = 2 = βˆ’ 2 , ● 1 = 2 = 2 = β€² 2 The value of at which the entire bias current I is steered into Q1 is = 1 + = √2 Output of differential pair taken single ended: ● Common-mode gain = | |= 2 , ● Differential gain = | |= 1 2 , ● CMMR=| |= Output of differential pair taken differentially: ● Common-mode gain = | |=0 , ● Differential gain = | |= , ● CMMR=| |=∞ Mismatch effect ( ) : ● =βˆ’ βˆ† 2 (Rd mismatch), ● CMMR=| | = 2 /( βˆ† ),● = 2 βˆ† ( β„Ž), ● CMMR=| |= 2 /( βˆ† ) Electronics II Formula Sheet by Haris H.

Transcript of Electronics Formula Sheet

Page 1: Electronics Formula Sheet

● Over drive Voltage: 𝑉𝑂𝑉 = (𝑉𝐺𝑆 βˆ’ 𝑉𝑑) ● π‘˜β€²π‘› = πœ‡π‘›πΆπ‘œπ‘₯ (𝐴/𝑉2)

● Cut off (𝑖𝐷 = 0): 𝑣𝐺𝑆 < 𝑉𝑑𝑛; ● Channel induced and Mosfet is in triode or saturation: 𝑣𝐺𝑆 = 𝑣𝑑𝑛 + 𝑣𝑂𝑉

Stats Triode region Saturation Region

Conditions 𝑣𝐺𝐷 > 𝑉𝑑

𝑣𝐷𝑆 < 𝑣𝑂𝑉 𝑣𝐺𝐷 ≀ 𝑉𝑑

𝑣𝐷𝑆 β‰₯ 𝑣𝑂𝑉

𝑖𝐷 1

2π‘˜β€²

𝑛

π‘Š

𝐿(𝑣𝑂𝑉 βˆ’

1

2𝑣𝐷𝑆)𝑣𝐷𝑆

1

2π‘˜β€²

𝑛

π‘Š

𝐿𝑣𝑂𝑉

2

● π‘”π‘š =𝑖𝑑

𝑣𝑔𝑠= π‘˜β€²

𝑛 π‘Š

𝐿𝑉𝑂𝑉 = π‘”π‘š = √2𝐾𝑛

β€² √𝐼𝐷√(π‘Š

𝐿) =

2𝐼𝐷

𝑉𝑂𝑉(4.6.2,6), ● 𝑉𝐴 =

1

πœ† , ● π‘Ÿπ‘œ =

|𝑉𝐴|

𝐼𝐷 , ● 𝐴𝑣 = βˆ’π‘”π‘š(𝑅𝐷||π‘Ÿπ‘œ),

Characteristic Parameters

MOSFET Voltage Gain, 𝐴𝑣 𝐺𝑣 Input

Resistance,𝑅𝑖 Output

Resistance,π‘…π‘œ

Common Source (Hybrid model)

βˆ’π‘”π‘š(𝑅𝐷||π‘Ÿπ‘œ||𝑅𝑙) βˆ’π‘…πΊ

𝑅𝐺 + π‘…π‘ π‘–π‘”π‘”π‘š(𝑅𝐷||π‘Ÿπ‘œ||𝑅𝑙) ∞ 𝑅𝐷||π‘Ÿπ‘œ

Common Source with a source resistance

(T-Model)

βˆ’π‘”π‘š(𝑅𝐷||𝑅𝑙)

1 + π‘”π‘šπ‘…π‘  βˆ’

𝑅𝐺

𝑅𝐺 + 𝑅𝑠𝑖𝑔

π‘”π‘š(𝑅𝐷||𝑅𝑙)

1 + π‘”π‘šπ‘…π‘  ∞ 𝑅𝐷

Common Gate (T-Model)

π‘”π‘š(𝑅𝐷||𝑅𝑙) 1

1 + π‘”π‘šπ‘…π‘ π‘–π‘”π‘”π‘š(𝑅𝐷||𝑅𝑙)

1

π‘”π‘š 𝑅𝐷

Common Drain (T-Model)

π‘Ÿπ‘œ||𝑅𝑙

(π‘Ÿπ‘œ||𝑅𝑙) +1

π‘”π‘š

𝑅𝐺

𝑅𝐺 + 𝑅𝑠𝑖𝑔.

π‘Ÿπ‘œ||𝑅𝑙

(π‘Ÿπ‘œ||𝑅𝑙) +1

π‘”π‘š

∞ 1

π‘”π‘š

● 𝑓𝑑 =π‘”π‘š

2πœ‹(𝐢𝑔𝑠+𝐢𝑔𝑑)(Unity Gain Frequency) ● 𝑅𝐿

β€² = 𝑅𝐷||π‘Ÿπ‘œ||𝑅𝐿 ● πΆπ‘’π‘ž = 𝐢𝑔𝑑(1 + π‘”π‘šπ‘…πΏβ€² ) ● 𝐢𝑖𝑛 = 𝐢𝑔𝑠 + πΆπ‘’π‘ž,

● 𝑓𝐻 =1

2πœ‹πΆπ‘–π‘›(𝑅𝑠𝑖𝑔||𝑅𝐺)(Upper 3-dB freq.)

Differential and multi-stage amplifier

Let I be the total current in common mode voltage

●𝑣𝐷1 = 𝑣𝐷2 = 𝑉𝐷𝐷 βˆ’πΌ

2𝑅𝐷, ● 𝑖𝐷1 = 𝑖𝐷2 =

𝐼

2= π‘˜β€²

𝑛 π‘Š

𝐿𝑣𝑂𝑉

2

The value of 𝑣𝑖𝑑 at which the entire bias current I is steered into Q1 is π‘£π‘–π‘‘π‘šπ‘Žπ‘₯ = 𝑣𝐺𝑆1 + 𝑣𝑠 = √2𝑉𝑂𝑉

Output of differential pair taken single ended:

● Common-mode gain = |𝐴𝐢𝑀| =𝑅𝐷

2𝑅𝑠𝑠 , ● Differential gain = |𝐴𝑑| =

1

2π‘”π‘šπ‘…π·, ● CMMR=|

𝐴𝑑

𝐴𝐢𝑀| = π‘”π‘šπ‘…π‘ π‘ 

Output of differential pair taken differentially:

● Common-mode gain = |𝐴𝐢𝑀| = 0 , ● Differential gain = |𝐴𝑑| = π‘”π‘šπ‘…π·, ● CMMR=|𝐴𝑑

𝐴𝐢𝑀| = ∞

Mismatch effect (π‘”π‘š π‘Žπ‘›π‘‘ 𝑅𝐷) :

●𝐴𝐢𝑀 = βˆ’βˆ†π‘…π·

2𝑅𝑠𝑠 (Rd mismatch), ● CMMR=|

𝐴𝑑

𝐴𝐢𝑀| = 2π‘”π‘šπ‘…π‘ π‘ /(

βˆ†π‘…π·

𝑅𝐷),● 𝐴𝐢𝑀 =

𝑅𝐷

2𝑅𝑠𝑠

βˆ†π‘”π‘š

π‘”π‘š( π‘”π‘šπ‘šπ‘–π‘ π‘šπ‘Žπ‘‘π‘β„Ž), ● CMMR=|

𝐴𝑑

𝐴𝐢𝑀| =

2π‘”π‘šπ‘…π‘ π‘ /(βˆ†π‘”π‘š

π‘”π‘š)

Electronics II Formula Sheet by Haris H.