Bjt saturation

MOSFET Question 4: The threshold voltage of an n-channel enhancement mode MOSFET is 0.5 V. When the device is biased at a gate voltage of 3 V, pinch-off would occur at a drain voltage of: 2 V. 2.5 V. 3 V. 1.5 V. Answer (Detailed Solution Below) Option 2 : 2.5 V.

The output characteristics of the BJT under common-emitter configuration are shown in Fig. 2.12. Three operating regions are distinct, namely, the cut-off region, the saturation region, and the active region. In power electronics applications the BJT is used as a switch and operates at the cut-off region or the saturation region. The transistor can be operated in three modes: Cut-off mode. Saturation mode. Active mode. In order to operate transistor in one of these regions, we have to supply dc voltage to the npn or pnp transistor. Based on the polarity of the applied dc voltage , the transistor operates in any one of these regions. May 22, 2022 · This creates \(I_B\). If properly designed, this current will be sufficient to put the BJT into saturation. The BJT acts as a switch, completing the circuit between the DC supply, the LED and the current limiting resistor, \(R_C\). For this to work reliably, we have to make sure that the ratio of saturation current to base current is much less ... Lecture 12-2 BJT Circuit Analysis • SPICE solves the system of nonlinear equations to obtain the voltages and currents • Is this circuit in the active region? Q1 Default RB 100E3Ω + 2V VIN RC 1E3Ω + 5V VCC IB 12.206 µA + VOUT 3.779 V +-VBE 779.365 mV IC 1.221 mA(i) Saturation Region In this region, both BJT junctions are forward biased. V CE is small, e.g. 50-100 mV, but quite large collector and base currents (I C & I B) can ow. This region is not used for ampli cation. There is a low resistance between the C and E terminals; the BJT acts like a closed switch. Figure 4 shows an actual circuit of a BJTThe minimum base current the BJT needs for saturation is: I B(min) = I C(sat) / ẞ (eq. 9) Note that I B should be significantly greater than I B(min) to be sure the BJT stays well into saturation. Finally, some inquisitive readers may be asking if there is a formula for V CE(sat). Indeed, there is, but as we’ve mentioned this quantity can ...

Correct design of Colpitts oscillator. I have been watching this video and when it is designing the colpitts oscillator it doesn't add a base resistor. I am thinking that is wrong because the BJT will saturate since the guy sets a base voltage 1/2VCC + VBE (0.7) to make the temperature dependent Vbe not important.If it's a miss, the solution values usually hint at the actual mode of operation—e.g., one assumes forward-active mode, but the solution values indicate the transistor cannot be in forward-active mode and is probably in saturation mode; so next you attempt a solution under the assumption the transistor is operating in saturation mode.1. In a BJT, Forward active mode is when Emitter Base Junction (EBJ) is forward biased and the Collector based junction (CBJ) is reverese biased. Saturation mode is when both Emitter Base Junction (EBJ) and the Collector based junction (CBJ) are forward biased. When you plot the output characteristics ( Ic Vs VCE ) the constant looking region ... • In order to prevent the BJT from entering very deeply into saturation, the collector voltage must not fall below the base voltage by more than 400 mV. V CC I C R C (V BE 400mV) A linear relationship can be derived for VCC and RC and an acceptable region can be chosen. Deep Saturation1. In a BJT, Forward active mode is when Emitter Base Junction (EBJ) is forward biased and the Collector based junction (CBJ) is reverese biased. Saturation mode is when both Emitter Base Junction (EBJ) and the Collector based junction (CBJ) are forward biased. When you plot the output characteristics ( Ic Vs VCE ) the constant looking region ...Saturation Region: In saturation region, both of the junctions of the BJT are in forward bias. This region is used for the ON-state of a switch where; i c = i sat. I sat is the …

BJT by which we mean bipolar junction transistor is a current-controlled device, you will, later on, get to know how it works. Keep reading! ... You can observe different regions for the output values, such as the Saturation region, Active region, and cut-off region of the graph, I hope by now you have a clear idea what these regions represent. ...The saturation region of a BJT (e.g. when turned on as a switch) corresponds to the triode/ohmic region of a MOSFET. Some authors also call the saturation region of a MOSFET the "active mode", which does match the terminology used for BJTs. But they also call the triode/ohmic region the "linear mode" which perhaps doesn't help that much because ...The minimum base current the BJT needs for saturation is: I B(min) = I C(sat) / ẞ (eq. 9) Note that I B should be significantly greater than I B(min) to be sure the BJT stays well into saturation. Finally, some inquisitive readers may be asking if there is a formula for V CE(sat). Indeed, there is, but as we’ve mentioned this quantity can usually be neglected …The term bipolar refers to the use of both holes and electrons as current carriers in the transistor structure. Figure 1: Basic BJT structure. The pn junction joining the base region and the emitter region is called the base-emitter junction. The pn junction joining the base region and the collector region is called the base-collector junction. With Vin = 5V, VB = 0.746V and VC = 0.024V which means that the BJT is operating in the saturation region. But I don't understand why. Vcc = 5V and Vin = 5V. RB = RC = 1k ohm. So I expect that VB = VC and the base-collector junction is reverse biased which means that the BJT is in the forward-active region.Saturation (for a BJT) is defined in several ways, but generally it relates to the collector-emitter voltage V CE. Here is an LTSpice simulation of a 2N4401 transistor driving a 160 ohm load with a 5V supply, which corresponds to about 30 mA collector current with the transistor turned ON.

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A bipolar junction transistor ( BJT) is a type of transistor that uses both electrons and electron holes as charge carriers. In contrast, a unipolar transistor, such as a field-effect transistor (FET), uses only one kind of charge carrier.22 thg 5, 2022 ... 1: The Saturating Switch. A good example of this is the saturating LED driver circuit shown in Figure 4.7.1 ...Electronics Tutorial about the Bipolar Transistor also called the Bipolar Junction Transistor or BJT including its Types and Construction.BJT saturation in an ideal transistor would result in a VCE of 0 V. Many transistors will show a VCEsat of 100-200 mV when the collector current is low enough, and VCE usually less than 0.5 V at their rated max collector current.

This collector-emitter saturation bulk resistance called RCE R C E is defined for Vce=Vce (sat) at Ic/Ib=10 at various currents. In some cases, the log-log, or linear graph of Ic vs Vce shows the linear property above 10% of Imax. example of Rce p.2 of 5 SOT-23. Prior to Zetex, you had to get a big power transistor in TO-3 can to get this low ...Lecture 10: BJT Physics 16 Simplified Circuit Mode Saturation Region • In the saturation region, both junctions are forward-biased, and the transistor operates with a small voltage between collector and emitter. v CESAT is the saturation voltage for the npn BJT. No simplified expressions exist for terminal currents other than i C + i B = i E.PNP transistor is another type of Bipolar Junction Transistor (BJT). The structure of the PNP transistor is completely different from the NPN transistor. The two PN-junction diodes in the PNP transistor structure are reversed with respect to the NPN transistor, such as the two P-type doped semiconductor materials are separated by a …Saturation is a fixed value. It is inherently stable and β β no longer matters. Effectively, when a BJT saturates, β β is forced to drop to whatever value is needed to …Mar 10, 2021 · The yellow region is the "linear", or "ohmic", or "triode" region. In the saturation region, the thick horizontal (well, slightly tilting upwards) straight lines (well, OK, curves) represent the (connected) points in the region of a particular Vgs value. So for example, the curve that the red dot sits represents the points of Vgs = 2.5V. Considering an n-p-n BJT, we have Vbe = 0.7 V (approx). Saturation starts to take place when the forward current from the Collector-Base junction starts to cancel out the collector current due to the carrier flow from the Emitter-Base junction.The minimum base current the BJT needs for saturation is: I B(min) = I C(sat) / ẞ (eq. 9) Note that I B should be significantly greater than I B(min) to be sure the BJT stays well into saturation. Finally, some inquisitive readers may be asking if there is a formula for V CE(sat). Indeed, there is, but as we’ve mentioned this quantity can usually be neglected …tions are critical to the operation of the BJT. BJTs are also simply known as bipolar transistors. 8.1 INTRODUCTION TO THE BJT A BJT is made of a heavily doped emitter (see Fig. 8–1a), a P-type base, and an N-type collector. This device is an NPN BJT. (A PNP BJT would have a P+ emitter, N-type base, and P-type collector.)Finding the Base-Emitter Voltage in an NPN Transistor. The problem asks to find the the real value of base-emitter voltage, VBE V B E and the corresponding IC I C, and VOUT V OUT in the figure below: VCE(sat) V C E ( sat) is given but the transistor is not necessarily in saturation mode; in fact, it's likely operating in the forward active mode ...Then just do nodal analysis and verify that current is flowing the correct way for a BJT in saturation. EDIT: This answer is for a saturated BJT. But the circuit shows an unusually biased BJT that is is actually not saturated, and probably more accurately described by two BJTs from base to collector and emitter, respectively.For the BJT in saturation, we can use an approach much like the one we use for a forward-biased diode or base-emitter junction. With the diode, we decided that ...Correct design of Colpitts oscillator. I have been watching this video and when it is designing the colpitts oscillator it doesn't add a base resistor. I am thinking that is wrong because the BJT will saturate since the guy sets a base voltage 1/2VCC + VBE (0.7) to make the temperature dependent Vbe not important.

A bipolar junction transistor is a three-terminal semiconductor device that consists of two p-n junctions which are able to amplify or magnify a signal. It is a current controlled device. The three terminals of the BJT are the base, the collector, and the emitter. A signal of a small amplitude applied to the base is available in the amplified ...

BJT: definition of "edge of saturation". The book Sedra/Smith (Microelectronic circuits) tells in chapter 5 the following: My question: I found no statement on why the EOS is defined by the point where vc < (vb - 0.4V). Seems like other books just define saturation at where vc < vb, and I even saw vc < (vb-0.7V) somewhere else.The transistor going into saturation isn't a property of the transistor itself, but instead a property of the circuit surrounding the transistor and the transistor, as part of it. A question about Vce of an NPN BJT in saturation region. For this circuit with ideal transistor (current controlled current source CCCS) any base current large than:A certain 2N3904 dc basis circuit with the following values is in saturation. Ib = 500 uA Vcc = 10V and Rc = 180 ohm and hfe = 150. If you increase Vcc to 15V, does the transistor come out of saturation? My attempt at a solution: Ic (sat) = (Vcc - Vce (sat))/Rc but Vce (sat) then work out whethere Ib is capable of producing Ic (sat) but Vce ...The BJT (7.1) BJT Physics (7.2) BJT Ebers-Moll Equations (7.3) ... Saturation Region (Low Output Resistance) Reverse Active (Crappy Transistor) Breakdown Linear Increase.The minimum base current the BJT needs for saturation is: I B(min) = I C(sat) / ẞ (eq. 9) Note that I B should be significantly greater than I B(min) to be sure the BJT stays well into saturation. Finally, some inquisitive readers may be asking if there is a formula for V CE(sat). Indeed, there is, but as we’ve mentioned this quantity can ...The minimum base current the BJT needs for saturation is: I B(min) = I C(sat) / ẞ (eq. 9) Note that I B should be significantly greater than I B(min) to be sure the BJT stays well into saturation. Finally, some inquisitive readers may be asking if there is a formula for V CE(sat). Indeed, there is, but as we’ve mentioned this quantity can ... Apr 3, 2011 · A Schottky diode is integrated into the transistor from base to collector. When the collector gets low when it's nearly in saturation, it steals base current which keeps the transistor just at the edge of saturation. The on state voltage will be a little higher since the transistor isn't fully saturated. Active mode - is the automobile cruising at a constant, controlled speed (constant, controlled collector current) as dictated by the driver. Saturation - the automobile driving up a steep hill that prevents it from going as fast …What is a BJT? A Bipolar Junction Transistor is a three-layer semiconductor device, consisting of two pn-junctions. ... Saturation and Cut-off Regions: BJTs operate in either the saturation region ...On the bottom end of the graph we can see the cutoff region, identified by IB ≤ 0μ, and the saturation region, identified by VCE ≤ VCEsat. The BJT unit could possibly be biased outside these indicated maximum limits, but the consequence of such process would result in being significant deterioration of the life of the device or total breakdown of the …

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To work as an open switch, a BJT operates in cut-off mode, here there is zero collector current, meaning ideally zero power is consumed by the BJT. On the other hand, to work as a closed switch, a BJT works in saturation mode, there are a high collector current and zero collector voltage, meaning ideally there is zero power consumed by the BJT.BJT operating modes zForward active – Emitter-Base forward biased – Base-Collector reverse biased zSaturation – Both junctions are forward biased zReverse active – Emitter-Base reverse biased – Base-Collector forward biased – Transistor operation is poor in this direction, becauseβis low: lighter doping of the layer designed to be the 19 thg 11, 2014 ... It will not increase the BOM cost anyway. You may also interested on these topics: 1. How to know if a transistor is saturated · 2. BJT ...Saturation Voltage. Vce(sat) When a BJT is turned on hard enough that the voltage drop in its collector load is sufficient to bring the collector potential below the base potential (in other words the base-collector junction is forward biased) it is said to be saturated. This saturation voltage is not proportional to the collector current, so ...Charge Transport in a BJT • Consider a reverse-biased pn junction: – Reverse saturation current depends on rate of minority-carrier generation near the junction ⇒can increase reverse current by increasing rate of minority-carrier generation: ¾Optical excitation of carriers ¾Electrical injection of minority carriers into thewe push the BJT into saturation, right? A: NO!! There is a big problem with this strategy as well! Remember, it is the total input voltage that will determine the BJT curve. If we DC bias the amplifier so that it is nearly in saturation, then even a small voltage v i can “push” the BJT into saturation mode. i C CE v CC C V R V CC active I C ...Since the BJT is a nonlinear device, it is hard to pinpoint an exact voltage that corresponds to saturation mode operation as opposed to active mode. Therefore, circuit analysis typically involves assigning a saturation collector-emitter voltage, \$ V_{CEsat} \$ , below which the device is said to be operating in saturation and above which the ... Saturation region. This is the region in which transistor tends to behave as a closed switch. The transistor has the effect of its collector and Emitter being shorted. The collector and Emitter currents are maximum in this mode of operation. The figure below shows a transistor working in saturation region.In the previous tutorial we saw that the standard Bipolar Transistor or BJT, comes in two basic forms. An NPN (Negative-Positive-Negative) configuration and a PNP (Positive-Negative-Positive) configuration.That is: an NPN transistor and a … ….

The minimum value of I B needed to produce saturation is. Normally, I B should be significantly greater than I B (min) to ensure that the transistor is saturated. Learn the Bipolar Junction Transistor (BJT) basics on this study guide from CircuitBread. The BJT is constructed with three doped semiconductor regions.The minimum value of I B needed to produce saturation is. Normally, I B should be significantly greater than I B (min) to ensure that the transistor is saturated. Learn the Bipolar Junction Transistor (BJT) basics on this study guide from CircuitBread. The BJT is constructed with three doped semiconductor regions.BJT Models Using the BJT Model Star-Hspice Manual, Release 1998.2 14-3 Control Options Control options affecting the BJT model are: DCAP, GRAMP, GMIN, and GMINDC. DCAP selects the equation which determines the BJT capacitances. GRAMP, GMIN, and GMINDC place a conductance in parallel with both the base-emitter and base-collector pn junctions.no diffusion from base to collector because it is reverse bias. when BJT is in saturation, in addition to this two currents there is another current which is ...BJT definition and characteristics. BJT transistor is a three terminal semiconductor device, based on three layers of p and n layers, with different doping concentration. BJT transistor can be two types – pnp and npn BJT transistor. Bipolar junction transistor (BJT) is characterised by three regions – base (B), collector (C) and emittor (E).It is a semiconductor device and it comes in two general types: the Bipolar Junction Transistor (BJT) and the Field Effect Transistor (FET). Here we will describe the system …Symbol of BJT. Bipolar junction Transistor shortly known as BJT has the following three components; Base. Emitter. Collector. All of the three components are represented in the symbol given below as B, E, and E. Refer to the diagram given below showing the symbol of NPN and PNP Bipolar Junction Transistors;Please note that the "saturation region" for a BJT is the region where Vce < Vce_sat. In this region of operation, Ic is not only determined by Ib and Vbe but also by Vce. If you would determine a small signal model of the BJT in the saturation region you would find an extra component "eating up" part of the collector current resulting in less ...• Study terminal characteristics of BJT. • Explore differences between npn and pnp transistors. • Develop the Transport Model for the bipolar device. Jaeger/Blalock 6/2/11 Microelectronic Circuit Design, 4E McGraw-Hill • Define four operation regions of BJT. • Explore model simplifications for each operation region. Bjt saturation, The consequences of electron-velocity saturation at the collector junction of an n-p-n biopolar junction transistor (BJT) are examined in a manner similar ..., 1. BJT: Regions of Operation • Forward active: device has high voltage gain and high β; • Reverse active: poor β; not useful; • Cut-off: negligible current: nearly an open circuit; • Saturation: device is flooded with minority carriers; – ⇒takes time to get out of saturation saturation cut-off reverse forward active VBC VBC VCE ... , The saturation current of a PN junction, as you correctly said, depends on the cross sectional area of the junction itself. In fact, if you look at a datasheet \$ I_{CBO} \gg I_{EBO} \$, confirming your idea.. Moreover, Sedra/Smith (I'm looking at the 6th edition, page 361) says: The structure in Fig. 6.7 indicates also that the CBJ has a much larger area than …, Jun 11, 2007 · 0. vce (sat) it means that the voltage of Vce is 0.6 in saturation mode of bjt. if. Ibβ>Ic BJT is in saturation. in active region. Ib = βIc. remove the bjt from the circuit then calculate the voltage across Vbe if Vbe is smaller than 0.7 (or threshold voltage of bjt) the BJT is in cutoff mode. Jun 12, 2007. , Bipolar Transistor in Saturation. When collector voltage drops below base voltage and forward biases the collector‐base junction, base current increases and the current gain factor, β, decreases. Large‐Signal Model for Saturation Region. , We would like to show you a description here but the site won't allow us., A BJT is obviously more complicated than your equation(s) provide. But those equations are often good enough when just considering the forward active region. To get a feel for the simplest DC model that was developed, see my answer to Why is Vbc absent from bjt equations?., Symbol of BJT. Bipolar junction Transistor shortly known as BJT has the following three components; Base. Emitter. Collector. All of the three components are represented in the symbol given below as B, E, and E. Refer to the diagram given below showing the symbol of NPN and PNP Bipolar Junction Transistors;, CBJ 의 Reverse-bias 를 Forward-bias 로 바꿨을 때, Saturation Mode 로 동작하게 된다. CBj 의 다이오드의 문턱 전압을 0.4V 라고 할 때, 위와 같은 그래프를 그릴 수 있다. Saturation 일 때 π type 으로 등가 회로를 그리면 위와 같으며 다이오드가 On 되어 하나 추가된 것을 볼 수 있다., 27 thg 1, 2020 ... When load line intersect IB = 0, it is known as cut off region of the transistor. As the base current is zero, only small collector leakage ..., 1. In a BJT, Forward active mode is when Emitter Base Junction (EBJ) is forward biased and the Collector based junction (CBJ) is reverese biased. Saturation mode is when both Emitter Base Junction (EBJ) and the Collector based junction (CBJ) are forward biased. When you plot the output characteristics ( Ic Vs VCE ) the constant looking region ..., At Saturation it moves towards DC steady state two, but before 2 is stabilised, the transistor is forward active again. (In this example I used, ... voltage across the capacitor cannot increase any further and this may remove the base recombination current from the BJT, for example. \$\endgroup\$ – jonk. Apr 14, 2021 at 23:38, The BJT as a Switch A BJT can be used as a switching device in logic circuits to turn on or off current to a load. As a switch, the transistor is normally in either cutoff (load is OFF) or saturation (load is ON). Figure 11: Switching action of an ideal transistor., • Bi lBipolar JtiJunction TitTransistor (BJT) (C t’d)(Cont’d) – BJT operation in saturation mode –PNP BJT – Examples of small signal models Reading: Chapter 4.5‐4.6 EE105 Spring 2008 Lecture 4, Slide 1Prof. Wu, UC Berkeley Bipolar Transistor in Saturation EE105 Spring 2008 Lecture 4, Slide 2Prof. Wu, UC Berkeley, In cutoff, the transistor appears as an open circuit between the collector and emitter terminals. In the circuit above, this implies Vout is equal to 10 volts. The second region is …, Finding the Base-Emitter Voltage in an NPN Transistor. The problem asks to find the the real value of base-emitter voltage, VBE V B E and the corresponding IC I C, and VOUT V OUT in the figure below: VCE(sat) V C E ( sat) is given but the transistor is not necessarily in saturation mode; in fact, it's likely operating in the forward active mode ..., Breakdown IB4 Active IB3 IB2 IB1 B =0 Cutoff VCE Figure 1. BJT characteristic curve IC + IB + VCE VBE - - IE E The characteristics of each region of operation are summarized …, , Saturation Region: In saturation region, both of the junctions of the BJT are in forward bias. This region is used for the ON-state of a switch where; i c = i sat. I sat is the saturation current & it is the maximum amount of current flowing between emitter and collector when BJT is in saturation region. Since both junctions are in forward bias ... , BJT: definition of "edge of saturation". The book Sedra/Smith (Microelectronic circuits) tells in chapter 5 the following: My question: I found no statement on why the EOS is defined by the point where vc < (vb - 0.4V). Seems like other books just define saturation at where vc < vb, and I even saw vc < (vb-0.7V) somewhere else., PNP BJT: Circuit Level Parameters B E C VCB=0 +-+-IC = FIE = FIB IE IB Current gain F: Current gain of the BJT in the forward active operation is defined as the ratio of the collector and base currents: C F B n aE E dB B p B C F I I D N W N W D I I Typical values of F are between 20-200 and: F: In the forward active operation F is defined as, In cut off region, both emitter to base and base to collector junction is in the reverse bias and no current flows through the transistor. The transistor acts as an open switch. In the saturation region, both the junctions are in forwarding bias, and the transistor acts as a closed switch. In cut off region the output of the transistor VCE, IC ... , The BJT (7.1) BJT Physics (7.2) BJT Ebers-Moll Equations (7.3) BJT Small-Signal Model. Department of EECS University of California, Berkeley EECS 105Fall 2003, Lecture 14 Prof. A. Niknejad ... Saturation Region (Low Output Resistance) Reverse Active (Crappy Transistor) Breakdown Linear Increase., The minimum base current the BJT needs for saturation is: I B(min) = I C(sat) / ẞ (eq. 9) Note that I B should be significantly greater than I B(min) to be sure the BJT stays well into saturation. Finally, some inquisitive readers may be asking if there is a formula for V CE(sat). Indeed, there is, but as we’ve mentioned this quantity can ..., Bjt Explanation Saturation. Yes, this is correct. The electric field of the depletion region (between the two junctions) can accelerate the charge carriers in the same direction as the diffusion current, and this current will be the collector-emitter current. Jan 26, 2021. #1., Explanation: If the collector-base junction and the base-emitter junction are both forward-biased, then the BJT functions in the saturation region of the output characteristics. 5. In a BJT, if the collector-base junction and the base-emitter junction are both reverse-biased, which region is the BJT operating in? a) Saturation region b) Active region c) Cutoff region, • In order to prevent the BJT from entering very deeply into saturation, the collector voltage must not fall below the base voltage by more than 400 mV. V CC I C R C (V BE 400mV) A linear relationship can be derived for VCC and RC and an acceptable region can be chosen. Deep Saturation , If it's a miss, the solution values usually hint at the actual mode of operation—e.g., one assumes forward-active mode, but the solution values indicate the transistor cannot be in forward-active mode and is probably in saturation mode; so next you attempt a solution under the assumption the transistor is operating in saturation mode., BJT는 Bipolar Junction Transistor의 약자로서 반도체 3개를 합쳐놓은 전류증폭소자! BJT (Bipolar Junction Transistor)에는 PNP형과 NPN형이 있으며, 베이스 (B), 컬렉터 (C), 에미터 (E) 3개의 전극을 가지고 있어~!! 그리고 BJT와 MOSFET이 있는데, BJT 의 전류는 전자와 정공 (양공) 둘다 ..., The transistor going into saturation isn't a property of the transistor itself, but instead a property of the circuit surrounding the transistor and the transistor, as part of it. A question about Vce of an NPN BJT in saturation region. For this circuit with ideal transistor (current controlled current source CCCS) any base current large than:, A Schottky diode is integrated into the transistor from base to collector. When the collector gets low when it's nearly in saturation, it steals base current which keeps the transistor just at the edge of saturation. The on state voltage will be a little higher since the transistor isn't fully saturated., Dec 26, 2015 · 8,625 21 31. In saturation region (where Vce<0.2V) the "beta" is much lower than in the active region (where Vce>0.2V); this makes Ic much smaller for a fixed base current in the saturation region. When one saturates transistor by achieving Vbe>=700mV, from now on the transistor will have a low beta since it is now in saturation region. , Definition of saturation: A collector current that produces a collector voltage Vc which is smaller than the base voltage Vb (npn case). That means: Because of Vbc>0 the base-collector junction now is forward biased (in contrast to the "normal" operation) and the base current Ib now consists of two parts (through the emitter and through the collector node).