What Reading Do We Get From Reversed Polarity

Control of photovoltaic engineering

Sukumar Mishra , Dushyant Sharma , in Electric Renewable Free energy Systems, 2016

19.5.1 PV supplying a DC system

Generally, a boost or buck–heave converter is used to increase the DC voltage and maintain MPPT; a scheme is shown in Figure 19.16. The output and input DC voltages are related by the duty cycle (D) [9] as:

Figure 19.sixteen. PV organisation supplying a DC load.

(19.17) $\frac{V_{\text{o}}}{V_{\text{i}}}=-\left(\frac{D}{1-D}\right)$

The minus sign shows the reverse polarity of the output voltage.

Case 19.8

A resistive load of fifteen Ω is fed through a buck–boost converter being supplied past the PV module given in Case nineteen.7. All the cells are receiving compatible irradiation of 700 W/m². Find the duty cycle at which the converter is operated so that maximum power is extracted from the PV module.

Solution

R ₅₀ = 15 Ω

Equally per Example 19.7, the voltage at maximum power is 42.96 V and the corresponding current is 5.403 A. Thus, the maximum ability the PV module can provide is P _max = 42.96 × 5.403 West = 232.112 Westward.

The power delivered to the load is $P_{\text{50}}=V_{\text{o}}^2/R_{\text{L}}$ . To extract maximum power, P _L = P _max.

Thus, $\frac{V_{\text{o}}^{\mathrm{two}}}{R_{\text{L}}}=232.112\text{W}$

$\Rightarrow 5_{\text{o}}=\sqrt{232.112\times R_{\text{L}}}=\sqrt{232.112\times 15}=59\text{5}\text{.}$

From (19.17), the boilerplate output voltage $5_0=\left(\frac{D}{1-D}\right){\mathrm{Five}}_{\text{i}}$ .

Thus, $V_0=D{5}_{\text{i}}+D{\mathrm{Five}}_0$ or $D=\frac{V_0}{V_0+V_{\text{i}}}=\frac{59}{42.96+59}=\frac{59}{101.96}=0.578$ .

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Advances in gas metal arc welding process: modifications in short-circuiting transfer mode

Dinbandhu , ... Kumar Abhishek , in Advanced Welding and Deforming, 2021

2.1 Polarities in GMAW

GMAW process operates on the principle of reverse polarity where a d.c. (direct current) ability supply is used with a positive signal assigned to the filler wire electrode. The power source has a abiding or flat voltage characteristic, as shown in Fig. 3.iv. It means that the arc length, which controls the voltage, significantly affects the welding current. When the arc length increases, the voltage also increases, and the current decreases. The wire feed speed regulates the electric current and affects the burnup speed of the filler wire electrode and so that the electrode wire could fire up slowly and stretch out back to its initial length. When the arc length reduces, the voltage declines, and the current rises. Due to this, the filler wire electrode burns up more than rapidly until it scorches back to its initial length. This is known as the self-regulating arc every bit the machine itself adjusts the arc length [11,12].

Figure 3.four. Constant voltage characteristics of a d.c. power source [eleven].

With kind permission from Elsevier.

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Multiphase Converters

Atif Iqbal , ... Kishore N. Mude , in Ability Electronics Handbook (Quaternary Edition), 2018

15.4.ii.iii Fifth Harmonic Injection PWM

The outcome of the addition of harmonic with reverse polarity in any signal is to reduce the summit of the reference point. Aim here is to bring the amplitude of the reference equally low as possible, so that the reference tin then be pushed to make it equal to the carrier, resulting in the college output voltage and better DC bus utilization. Using this principle, third harmonic injection PWM scheme is used in a 3-phase VSI that results in increase in the key output voltage to 0.575 V_dc [32,35]. Third harmonic voltages do not announced in the output phase voltages and are restricted to the leg voltages only. Post-obit the same principle, fifth harmonic injection PWM scheme can be developed to increase the modulation index of a five-stage VSI.

The reference leg voltages are given as

(fifteen.98) $\begin{array}{l}{V}_{ao}^{⁎}=\mathrm{0.five}{M}_1{V}_{\mathit{dc}}cos\left(\omega t\right)+0.5M_5{V}_{\mathit{dc}}cos\left(5\omega t\right)\\ V_{\mathit{bo}}^{⁎}=0.5{\mathrm{Thousand}}_1{5}_{\mathit{dc}}cos\left(\omega t-2\pi /5\right)+0.5{\mathrm{Thou}}_5{V}_{\mathit{dc}}cos\left(5\omega t\right)\\ V_{co}^{⁎}=0.5M_1{V}_{\mathit{dc}}cos\left(\omega t-4\pi /5\right)+0.5M_5{V}_{\mathit{dc}}cos\left(5\omega t\right)\\ V_{\mathit{do}}^{⁎}=0.5{\mathrm{Yard}}_{\mathrm{i}}{V}_{\mathit{dc}}cos\left(\omega t+4\pi /\mathrm{v}\right)+0.5M_{\mathrm{v}}{V}_{\mathit{dc}}cos\left(5\omega t\right)\\ V_{eo}^{⁎}=0.5M_{\mathrm{one}}{5}_{\mathit{dc}}cos\left(\omega t+\mathrm{ii}\pi /5\right)+0.5{\mathrm{One\; thousand}}_5{\mathrm{Five}}_{\mathit{dc}}cos\left(\mathrm{v}\omega t\right)\end{array}$

Information technology is to be noted that 5th harmonic has no result on the value of the reference waveform when $\omega t=\left(2\mathrm{thousand}+1\right)\pi /\mathrm{x}$ , since $cos\left(\mathrm{v}\left(\mathrm{two}k+\mathrm{i}\right)\pi /10\right)=0$ for all odd k. Thus, Thou ₅ is chosen to brand the peak magnitude of the reference of (15.98) that occurs where the fifth harmonic is nada. This ensures the maximum possible value of the fundamental component. The reference voltage reaches a maximum when

(15.99) $\frac{d{5}_{ao}^{⁎}}{dt}=-0.5M_{\mathrm{ane}}{V}_{\mathit{dc}}sin\omega t-0.5\cdot \mathrm{v}{\mathrm{Chiliad}}_5{V}_{\mathit{dc}}sin\mathrm{five}\omega t=0$

This yield

(15.100) $M_{\mathrm{v}}=-{\mathrm{Grand}}_1\frac{sin\left(\pi /\mathrm{x}\right)}{5}\mathrm{f}\mathrm{o}\mathrm{r}\omega t=\pi /10$

Thus, the maximum modulation index can be determined from

(15.101) $\left|V_{ao}^{⁎}\right|=\left|0.5M_{\mathrm{ane}}{V}_{\mathit{dc}}cos\left(\omega t\right)-\mathrm{0.v}\frac{sin\left(\pi /\mathrm{x}\right)}{5}{\mathrm{Chiliad}}_1{V}_{\mathit{dc}}cos\left(\mathrm{iii}\omega t\right)\right|=\mathrm{0.v}{V}_{\mathit{dc}}$

The in a higher place equation gives

(15.102) $M_1=\frac{1}{cos\left(\pi /10\right)}\mathrm{f}\mathrm{o}\mathrm{r}\omega t=\pi /10$

Thus, the output central voltage is increased by 5.fifteen% higher than the value obtainable using simple carrier-based PWM by injecting vi.18% fifth harmonic in fundamental. The fifth harmonic is in contrary stage to that of the fundamental.

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LT1070 design manual

Carl Nelson , in Analog Circuit Pattern, 2011

Combined cadet-boost regulator

Cadet-boost regulators (Effigy 5.12 ) are used to generate an output with the reverse polarity of the input. They look similar to a boost regulator except that the load is referred to the inductor side of the input instead of the switch side. Buck-boost regulators have an output voltage given by:

Figure v.12. Inverting Topology

(eight) ${\text{V}}_{\text{OUT}}=-{\text{V}}_{\text{IN}}\left(\frac{\text{DC}}{1-\text{DC}}\right)$

With duty bicycle varying between 0 and 1, the output voltage tin vary between zero and an infinitely loftier value. The current and voltage waveforms evidence that, like boost regulators, the peak switch, diode, and output capacitor currents tin can be significantly higher than output currents and these components must be sized accordingly.

(nine) ${\text{I}}_{\text{Superlative}}=\frac{{\text{I}}_{\text{OUT}}}{\mathrm{i}-\text{DC}}={\text{I}}_{\text{OUT}}\frac{({\text{Five}}_{\text{OUT}}+{\text{V}}_{\text{IN}})}{{\text{V}}_{\text{IN}}}(\text{continuous}\text{mode})$

Maximum switch voltage is equal to the sum of input plus output voltage. The forwards plough-on time of D1 is therefore very important in higher voltage applications to forestall additional switch stress.

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Switch-Mode Power Supplies

Jean Pollefliet , in Power Electronics, 2018

two.iii Buck-boost converter

2.three.i Operation of buck-boost converter

Fig. 13-9 shows the basic configuration. Closing S causes a electric current i_L to menstruum and magnetic energy is stored in the coil $\left(\frac{1}{2}\cdot L\cdot i_L^2\right)$ .

Fig. thirteen-9. Bones principle of buck-heave converter

When the switch opens, the magnetic energy can only be discharged in the load and this results in a reverse polarity of the output voltage V_o with respect to V_i . The capacitor once once more functions as a filter capacitor.

As with a boost converter nosotros kickoff store energy in the coil and pump this free energy to the load when the switch is open. This explains why both converters are classified as flyback converters.

Once once more nosotros distinguish between two operating modes, namely continuous and discontinuous current mode in the coil.

two.3.2 Continuous current in the whorl

Fig. thirteen-10a shows the associated waveforms. When the switch closes a voltage results across the coil:

Fig. thirteen-ten. Waveforms of fig. thirteen-ix

(xiii-xiv) $v_L=V_i=\mathrm{50}.\frac{\Delta i}{\Delta t}=L.\frac{\mathit{(}{I}_{\mathrm{ane}}\mathit{‐}{I}_{\mathrm{two}}\mathit{)}}{\delta .T}\mathrm{or}:\mathrm{50}.\mathit{(}{I}_1\mathit{‐}{I}_2\mathit{)}=\delta \mathit{.}T\mathit{.}{V}_i$

.

When the switch opens after neglecting $v_D:v_L=V_o=\mathrm{Fifty}\frac{\Delta i}{\Delta t}=L.\frac{\mathit{(}{I}_2\mathit{‐}{I}_1\mathit{)}}{\mathit{(}\mathit{1}-\delta \mathit{)}.T}\mathrm{or}:$

(13-15) $\mathrm{50}.\mathit{(}{I}_2\mathit{‐}{I}_1\mathit{)}=V_o.\mathit{(}\mathit{1}-\delta \mathit{)}.T$

From (13-14) and (13-fifteen) it follows:

(13-sixteen) $V_o=-V_i\cdot \frac{\delta }{1-\delta }$

2.3.3 Discontinuous current in the coil

In this example the energy in the coil is completely discharged before the transistor switch redoses. Once more there is a dead fourth dimension t_d (discontinuous current). Fig. 13-10b shows the associated waveforms. Closing the switch Due south results in a voltage across the coil, whereby

(13-17) $V_i=v_{\mathrm{Fifty}}=\mathrm{Fifty}.\frac{\Delta i}{\Delta t}=\mathrm{50}.\frac{I_{\mathit{1}}}{\mathrm{\delta }.T}\mathrm{or}:L\mathit{.}{I}_{\mathit{1}}=\delta .T.V_i$

Afterwards the switch opens during the time interval (one — δ). T — t_d nearly all the energy in the coil is gone. The voltage across the curlicue is at present Five_o and the electric current changes from I_one to zip, then that:

(thirteen-18) ${\mathrm{Five}}_o=v_L=L.\frac{\mathit{(}\mathit{0}-I_{\mathit{i}}\mathit{)}}{\left[\mathit{(}\mathit{1}-\delta \mathit{)}\mathit{.}T-t_d\right]}\to \to L.I_{\mathit{1}}=-{\mathrm{Five}}_o.\left[\mathit{(}\mathit{ane}-\delta \mathit{)}\mathit{.}T-t_d\right]$

From (xiii-17) and (13-18) it follows that: $\delta .T.V_i=-V_o.\left[\mathit{(}\mathit{1}-\delta \mathit{)}\mathit{.}T-t_d\right]$

from which:

(thirteen-nineteen) $5_o=-V_i\cdot \frac{\delta }{1-\delta -t_d/T}$

2.3.iv

Remarks

ane.

From (13-xvi) and (xiii-xix) it follows that the buck-boost converter results in voltage inversion.

ii.

Depending on the value of Southward we have | V_o | ≤ or ≥ | Five_i |. This is therefore a step-upward /pace- down converter.

3.

The maximum voltage beyond the (transistor) switch is V_i + V_o as tin can be seen in fig. 13-10 at the bottom.

4.

The maximum contrary voltage across the diode is V_i + Five_o .

ii.3.5 Numeric case 13-3:

For a cadet boost converter with continuous current mode we are given:

• input voltage: Fivei = iii to 15   Five	• max.output current: Io = 3A
• output voltage: 5o = 9   V ± 0.ane%	• chopper frequency: f = 100   kHz

Required: Determine the values of L and C.

Solution:

$\begin{array}{l}\mathrm{From}\left(13-\mathrm{xvi}\right)\to \to V_o=V_{\mathit{imax}}\cdot \frac{{\delta }_{\mathit{min}}}{\mathit{(}\mathit{one}-{\delta }_{\mathit{min}}\mathit{)}}\to \to {\delta }_{\mathit{min}}=\frac{V_o}{V_{\mathit{imax}}+V_o}=\frac{9}{\mathrm{xv}+9}=0.375.\\ \text{Assumption}\Delta i_{\mathit{Lmax}}=0.2\cdot I_o=0.6\mathrm{A}\\ \mathrm{From}\left(\mathrm{thirteen}‐15\right)\to \to L_{\mathit{max}}=V_o\cdot \frac{\mathit{(}\mathit{1}-{\delta }_{\mathit{min}}\mathit{)}\cdot T}{\Delta i_{\mathrm{Fifty}}}=\frac{9\cdot \left(\mathrm{one}-0.375\right)\cdot {10}^{-\mathrm{five}}}{\mathrm{0.half\; dozen}}=93.75\mathrm{\mu }\mathrm{H}\\ \mathrm{From}\left(\mathrm{xiii}‐7\right)\to \to C_{\mathit{min}}=\frac{\Delta i_L}{8\cdot f\cdot \Delta v_{\mathit{Cmax}}}=\frac{\mathrm{0.vi}}{\mathrm{viii}\cdot {10}^5\cdot 9\cdot {10}^{-3}}=\mathrm{83.iv}\mathrm{\mu }\mathrm{F}\\ \mathrm{and}:\mathrm{Eastward}\mathrm{South}{R}_{\mathit{max}}=\frac{\Delta v_{\mathit{omax}}}{\Delta i_{\mathrm{Fifty}}}=\frac{0.1\%\cdot 9}{\mathrm{0.half\; dozen}}=0.015\Omega \end{array}$

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Electrochemical Spark Machining

Anjali V. Kulkarni , Vijay K. Jain , in Hybrid Machining, 2018

6.five.5 Some New Observations in ECSM of Quartz

Experimental investigations on the performance of ECSM process for cutting quartz plate and chemical analysis of the reaction products have been carried out. Both reverse polarity (ECSMWRP, wherein cathode or tool is negatively polarized) and directly polarity (ECSMWDP, wherein tool is positively polarized) have been applied and the comparative study has been performed under the same experimental conditions [seven]. A small-scale electrode was fabricated cathode or anode by irresolute the polarity. Sparking occurs between the tool and electrolyte because of breakup of the insulating bubble due to high potential gradient across the gas bubble. Experimental observations reveal that spark intensity is higher at the small electrode, when information technology is a cathode compared to when information technology is an anode. But, material removal rate, penetration rate (PR), overcut, and tool wear rate (TWR) are higher in direct polarity compared to reverse polarity, equally can be observed in Tabular array vi.2. Therefore, it seems that material removal in reverse polarity is not only by melting and vaporization of workpiece cloth. Deep craters formed on the anode at the anode–workpiece interface atomic number 82 to conclude that some chemical reaction is occurring at anode–workpiece interface.

Table half-dozen.2. Comparing Between Reverse Polarity and Direct Polarity Performance (Machining Parameters: 72V, NaOH Electrolyte Concentration 10% past Weight) [7]

Tool	Machining time (min)	Workpiece (mg)		Tool (mg)		Overcut (mm)	Machined Depth (mm)	MRR (mg/min)	TWR (mg/min)	PR (mm/min)
		Initial weight	Concluding weight	Initial weight	Final weight
Positive ECSMWRP	23.724	0.456	0.421	0.429	0.416	0.175	6.66	i.47	0.548	> 0.339
Negative ECSMWDP	59.310	0.909	0.876	0.411	0.408	0.108	7.175	0.343	0.050	~ 0.120

Experimental observations reveal that spark intensity is college at the pocket-size electrode, when information technology is a cathode compared to when it is an anode. Simply, material removal rate, PR, overcut, and TWR are higher in contrary polarity compared to directly polarity.

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PIPELINE GIRTH WELDING USING THE FLUX-CORED ARC WELDING PROCESS

R.M. Huntley , ... A.B. Rothwell , in Welding in Energy-Related Projects, 1984

Operating Characteristics

Gas-shielded FCAW. One wire (wire ane, Tabular array 2) was evaluated for semi-automatic, downhill welding on cross-country pipelines. This contrary-polarity wire, which was specifically designed for multi-pass, vertical downwards applications, exhibited a soft arc in the spray mode. Slag cover was thin and easily removed by ability brushing: smoke was not a problem. Minimal spatter and piece of cake cleaning resulted in this wire being rated high in operator entreatment. Though diverse gas mixtures were tried, 75% Ar/25% C0_ii provided the best operating characteristics.

The training of stovepipe welders to use this consumable arrangement could be expected to be minimal, since the techniques are essentially the same equally for conventional SMAW. It is felt that most qualified welders would exist able to produce quality weldments consistently afterwards at nearly one week.

The gas-shielded vertical-upwards trials used a mechanized welding system incorporating a bug which travels circumferentially effectually the pipe on a steel band (Fig. 2). Individual controls for domicile at the bevel edges and for adjusting travel speed and wire-feed speed ease the welding operation. This allowed for procedures to be developed which optimize the deposition characteristics of the process and minimize operator manipulation.

Fig. 2. CRC M200 welding bug

In developing parameters and techniques, it was found that the critical point was in the 45° overhead position. Since the fluidity of the weld pool and slag is relatively loftier, in that location is a trend for the molten pool to "fall out" at this indicate. Some other critical aspect was bead placement. Considering of the rather shallow penetration characteristics of these wires, each laissez passer must maintain a reasonably flat profile: if a previously-deposited pass is convex and is not ground properly, lack of inter-laissez passer fusion can occur.

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The TIG welding process

Peter W Muncaster , in A Applied Guide to TIG (GTA) Welding, 1991

Modes

•

DC – direct current, electrode negative, work positive. Sometimes known as direct, i.e. unpulsed DCEN (or DCSP in the USA), Fig. 1.1.

1.one. DCEN polarity.

•

DC reverse polarity, electrode positive, work negative (not used every bit widely), DCEP (or DCRP in the USA), Fig. 1.2.

1.2. DCEP polarity.

Annotation: The terms DCEN and DCEP are preferable as they signal electrode polarity for both the above.

•

Air-conditioning – alternating current. In this manner arc polarity chop-chop changes giving some cathodic cleaning consequence, platonic for aluminium where oxides apace develop in the weld bead, and for some stainless steels. An Ac/DC power source gives the ability to select either DC or AC equally the occasion arises and would be the best purchase for a general fabrication shop where many different metals of varying thickness to weld would often be encountered, Fig. i.iii.

i.iii. Ac operation.

•

Pulsed DC – This way allows the arc to exist pulsed at various rates between selectable high and low current settings and gives greater control of rut in the arc area.

TIG welding is clean, toll-effective, albeit a bit tedious compared with metal inert gas (MIG) and metal active gas (MAG) welding, can be used by manus or automated and will weld a vast range of metals and thicknesses in several different modes. Whatever mode is used, the process remains the aforementioned, namely that the metals to be joined are fused together past the heat of an electric arc inside a shield of inert gas which surrounds the arc and prevents undue oxidation of the metal. The arc is struck between the electrode and the workpiece and, in all simply a very few cases, the electrode is made from tungsten, oft with small quantities of a rare metallic alloyed into the finished electrode rod.

A TIG arc is very hot and localised providing a means of applying maximum oestrus for welding in a pocket-size area, allowing an experienced welder to produce peachy, meaty weld beads with excellent penetration and forcefulness.

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Microelectrical discharge machining of Ti-6Al-4V

G. Kibria , B. Bhattacharyya , in Microfabrication and Precision Engineering, 2017

4.6.1.7 Polarity

Polarity refers to the electrical conditions determining the management of the current catamenia relative to the electrode. The polarity condition of the electrodes is of two types, (1) straight polarity and (2) opposite polarity. Directly polarity is that condition when the microtool is connected to the cathode (−), whereas opposite polarity is that condition in which the tool electrode is connected to the anode (+) and the workpiece to the cathode (−). To achieve high MRR from the workpiece, the tool electrode is used equally the cathode and the workpiece as the anode. Depending on the application, some electrode/work material combinations provide better results when the polarity is inverse. Generally for graphite electrodes, a positive polarity gives a better vesture condition, whereas a negative polarity gives better machining speed.

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Reliability of optoelectronics

J.-S. Huang , in Reliability Characterisation of Electrical and Electronic Systems, 2015

half-dozen.6.2 ESD polarity result

The ESD failure threshold as a function of polarity was likewise investigated. Figure vi.21 shows the box plot of the ESD damage threshold of forwards (F), contrary (R), and forward/reverse (F/R) polarities. The box contains the heart 50% of the data, with the upper and lower edges of the box indicating the 75% and 25% the data points, respectively. The line in the box indicates the median value of the data. The ends of the vertical line indicate the maximum and minimum data values, and the points exterior the ends of the line represent outliers. For each polarity, the statistical box plot consists of chip-based information, with each data point representing one scrap. There were three to 6 wafers tested for each polarity. For the forward polarity, the chips showed no failure at 5   kV. After beingness exposed to a v-kV frontwards bias, the devices showed no change in the threshold current and SE. To verify the functionality, devices were sampled to test the optical spectrum, and the results showed good DFB peak and SMSR. For graphing purposes, 5-seven   kV was assigned to the forrard-bias group in Figure 6.21 . For the contrary polarity, the majority of the laser devices exhibited shifts in the threshold current and optical power in the range of 2.5-iv.0  kV. The most heady observation was that ESD damage threshold was the lowest for the combination of forward and reverse polarities, ranging from 2.ii to three.two   kV.

Figure 6.21. Box plot of the ESD damage thresholds of frontward, opposite, and forward/opposite polarities.

Because both Au/Zn and Ti/Pt/Au p-metal systems have been used in manufacture, nosotros investigated the correlation of ESD performance and p-metal. Table 6.eight shows the ESD damage thresholds of Au/Zn wafers under F, R, and F/R bias. The ESD threshold represents the median value of each wafer. Table 6.9 shows ESD damage thresholds of Au/Ti/Pt/Au wafers under F, R, and F/R polarities. On the wafer basis, the ESD threshold is the highest for the forward polarity and the lowest for the F/R polarity. Once more, similar dependence of polarity was observed. For each polarity, Au/Ti/Pt/Au and Au/Zn show comparable ESD thresholds.

Table six.8. Median values (kV) of ESD failure thresholds from Au/Zn wafers

ESD polarity	Wafer B-ane	Wafer B-2	Wafer B-3	Wafer B-iv	Wafer B-5
Forrard	>   5	>   5	>   5	>   five	>   5
Contrary	2.62	3.98	3.threescore	3.03	ii.41
R/F	two.18	ii.79	2.70	2.94	ii.32

After Ref. [83].

Table 6.9. Median values (kV) of ESD failure thresholds from Au/Ti/Pt/Au wafers

ESD polarity	Wafer A-1	Wafer A-2	Wafer A-3	Wafer A-4	Wafer A-v
Forward	>   five	>   5	>   five	>   v	>   5
Reverse	iii.thirteen	3.25	3.25	3.thirteen	2.88
R/F	three.06	–	3.25	2.50	2

After Ref. [83].

The lower reverse ESD threshold is attributable to the avalanche breakup effect. Figure 6.22 shows the example of forward and contrary current every bit a function of applied voltage (5) in logarithmic scale. The I-V bend is based on the 360-μm cavity BH laser. The Joule heating, known as ohmic heating, is given by Equation (6.7) according to Joule's first law.

Figure six.22. Forrad and opposite I-V curves of BH lasers shown in logarithmic scale. The I-V is based on the 360-μm cavity BH laser.

After Ref. [83].

(six.7) $Q=A{I}^{\mathrm{two}}R$

where A is a constant, Q is the estrus release through a device by the passage of an electrical current, I is the electrical current, and R is the resistance. The reverse current is roughly 4 to five orders of magnitude smaller than the forward current.

For the same applied voltage, the contrary electric current at the forward bias is higher than that at the reverse bias, but the resistance is lower at the forward bias. As a result, the Joule heating, proportional to the square of electric electric current, is lower at the contrary bias by about four to v orders of magnitude, equally shown in Table 6.10. Hence, the barrage breakup resulting from the tunneling machinery may be responsible for the opposite ESD failure. For the F/R polarity, the ESD threshold does not appear to correlate to the lodge of frontwards and reverse bias. The lower ESD threshold of F/R polarity, compared to the forwards and contrary bias alone, could be related to the memory/cumulative effect. The cumulative ESD result has been observed in ICs [84–86].

Tabular array six.10. Instance of joule heating of forward and contrary bias based on the operation of BH InP semiconductor lasers (360   μm in cavity length).

	Applied voltage, V (V)	Electric current, I (A)	Resistance, R (Ω)	Q (W)
Forward bias	ane.0	5.4   ×   10−   iii	9.0	two.6   ×   x−   iv
	1.8	9.iv   ×   10−   2	nine.0	ane.4   ×   x−   1
Reverse bias	−   one.0	−   1.ane   ×   ten−   7	iii.0   ×   ten−   5	3.6   ×   10−   9
	−   i.eight	−   2.8   ×   x−   six	three.0   ×   ten−   5	4.1   ×   x−   6

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