EE 331 - Devices and Circuit

EE 331 MOC

$I d = I s (e^{\frac{V d}{V t}} - 1)$

$V r = \frac{V p - V o n}{R C} T$ or $V r = \frac{V p - V o n}{f R C}$ Where T is the period and $f = \frac{1}{T}$

Rectifiers

Reduce Ripple Voltage

$Δ T$ is the charging time of the capacitor or the diode conduction interval

$Δ T = \frac{1}{ω} \sqrt{2 * \frac{V_{r}}{V_{p}}}$

$Δ T = \frac{5}{4} T - t_{1}$

$T ≫ Δ T$
$R C ≫ (T - Δ T)$
Investigate further

$V_{1} = (V_{p} - V_{o n}) - V r = V_{o n} (t = t_{1})$

$I_{l} (t) = \frac{V_{o} (t)}{R}$ so $I_{l} (t)_{m a x} = \frac{V_{o} (t)_{m a x}}{R}$

When $R C$ is very large, $I_{l, m i n} ≃ I_{l, m a x}$
$\frac{T}{R C} ≃ 0$ when $R C ≫ T$

Semiconductors

Semiconductor Discussion

Silicon has 14 electrons in it's standard configuration, it's outer shell is the most critical. With 8 electrons on outer shell, Silicon is stable

Intrinsic Semiconductors

$n = p = n i = B T^{\frac{3}{2}} e^{\frac{- E g}{2 k t}}$

$n$ is number of electrons per cm3
$p$ is number of holes per cm3
$T$ is the temperature in Kelvin
$B$ is the material property

For silicon, $n i ≃ 1.5 * 10^{10}$

EE 331 - Devices and Circuit

EE 331 MOC

$V r = \frac{V p - V o n}{R C} T$ or $V r = \frac{V p - V o n}{f R C}$ Where T is the period and $f = \frac{1}{T}$

Rectifiers

Reduce Ripple Voltage

$Δ T$ is the charging time of the capacitor or the diode conduction interval

$Δ T = \frac{5}{4} T - t_{1}$

$V_{1} = (V_{p} - V_{o n}) - V r = V_{o n} (t = t_{1})$

$I_{l} (t) = \frac{V_{o} (t)}{R}$ so $I_{l} (t)_{m a x} = \frac{V_{o} (t)_{m a x}}{R}$

Semiconductors

Semiconductor Discussion

Intrinsic Semiconductors

$n = p = n i = B T^{\frac{3}{2}} e^{\frac{- E g}{2 k t}}$

Doped Semiconductors

N-Type

P-Type

EE 331 MOC

Vr=Vp−VonRCT or Vr=Vp−VonfRC Where T is the period and f=1T

Rectifiers

Reduce Ripple Voltage

ΔT is the charging time of the capacitor or the diode conduction interval

ΔT=54T−t1

V1=(Vp−Von)−Vr=Von(t=t1)

Il(t)=Vo(t)R so Il(t)max=Vo(t)maxR

Semiconductors

Semiconductor Discussion

Intrinsic Semiconductors

n=p=ni=BT32e−Eg2kt

Doped Semiconductors

N-Type

P-Type

$V r = \frac{V p - V o n}{R C} T$ or $V r = \frac{V p - V o n}{f R C}$ Where T is the period and $f = \frac{1}{T}$

$Δ T$ is the charging time of the capacitor or the diode conduction interval

$Δ T = \frac{5}{4} T - t_{1}$

$V_{1} = (V_{p} - V_{o n}) - V r = V_{o n} (t = t_{1})$

$I_{l} (t) = \frac{V_{o} (t)}{R}$ so $I_{l} (t)_{m a x} = \frac{V_{o} (t)_{m a x}}{R}$

$n = p = n i = B T^{\frac{3}{2}} e^{\frac{- E g}{2 k t}}$