Consider a long-channel NMOS transistor with source and body connected together- Assume that the electron mobility is independent of VGS and VDS Given-gm - 0-5 - A-V for VDS- 50 mV and VGS- 2 V- gd - 8 - A-V for VGS- 2 V and VDS- 0 V-where gm - - ID- VGS and gd - - ID- VDSThe threshold voltage in volts of the transistor is

Since V_GS gt; V_DS, MOSFET is in linear operation I_D = K' _N [V_GS V_T] V_DS dI_DdV_GS = K'_N V_DS g_m = K'_N V_DS 0.5× 10^ 6 = K'_N [50× 10^ 3] ∴ K'_N ...

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Byju's Answer

Standard XII

Physics

Using Lenz's Law

Consider a lo...

Question

Consider a long-channel NMOS transistor with source and body connected together. Assume that the electron mobility is independent of $V_{G S}$ and $V_{D S}$ Given,
$g_{m} = 0.5 μ A / V$ for $V_{D S} = 50 m V$ and $V_{G S} = 2 V, g_{d} = 8 μ A / V$ for $V_{G S} = 2 V$ and $V_{D S} = 0 V$ ,
where $g_{m} = \frac{δ I_{D}}{δ V_{G S}}$ and $g_{d} = \frac{δ I_{D}}{δ V_{D S}}$
The threshold voltage (in volts) of the transistor is
1.2

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Solution

The correct option is A 1.2
Since $V_{G S} > V_{D S}$ , MOSFET is in linear operation
$I_{D} = K_{N}^{'} [V_{G S} - V_{T}] V_{D S}$
$\frac{d I_{D}}{d V_{G S}} = K_{N}^{'} V_{D S}$
$g_{m} = K_{N}^{'} V_{D S}$
$0.5 \times 10^{- 6} = K_{N}^{'} [50 \times 10^{- 3}] ∴ K_{N}^{'} = 10^{- 5}$
$I_{D} = K_{N}^{'} [V_{G S} - V_{T}] V_{D S}$
$\frac{d I_{D}}{d V_{D S}} = K_{N}^{'} [V_{G S} - V_{T}]$
$g_{d} = K_{N}^{'} [V_{G S} - V_{T}]$
$8 \times 10^{- 6} = 10^{- 5} [2 - V_{T}]$
On solving $V_{T} = 1.2 V$

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The correct option is A 1.2Since VGS>VDS, MOSFET is in linear operation ID=K′N[VGS−VT]VDS dIDdVGS=K′NVDS gm=K′NVDS 0.5×10−6=K′N[50×10−3] ∴K′N=10−5 ID=K′N[VGS−VT]VDS dIDdVDS=K′N[VGS−VT] gd=K′N[VGS−VT] 8×10−6=10−5[2−VT] On solving VT=1.2V