IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 38, NO. 9, SEPTEMBER 2023

10669

Search Method of Robust Gate Driving Vectors for
Digital Gate Drivers With Low Test Cost Against
Load Current and Temperature Variations in IGBTs
Ting-Wei Wang , Student Member, IEEE, Toshiaki Inuma, Po-Hung Chen , Senior Member, IEEE,
and Makoto Takamiya , Senior Member, IEEE

Abstract—A digital gate driver with active gate driving is effective in solving the tradeoff between switching loss and current/voltage overshoot of power devices. However, the optimum
gate driving vector (GV) for a digital gate driver is temperatureand load current-dependent. When an optimum GV at a particular
operating condition is reused to another, the switching performancesometimes becomes worse than the conventional gate drive (Saiet al. 2019). Therefore, robust gate driving vectors (RGVs) against
temperature and load current variation are required (Sai et al.
2019). Nevertheless, the test cost of searching for an RGV is veryhigh. In order to reduce the test cost, search methods of RGVwith fewer required measurements are proposed in this article.
Single-step GV and stop-and-go GV are selected as the type of
RGV for turn-ON and turn-OFF, respectively. Compared with theconventional search method of RGV in Sai et al. 2019 and Wanget al. 2020, the proposed search method can reduce the measurement time by 99% and 92%, respectively. Furthermore, when the
RGV and the optimum GV at a single condition are reused to otheroperating conditions, the maximum overall fOBJ of RGV is lower
than that of the single condition optimum GV, which shows thatthe searched RGV has better robustness.
Index Terms—Gate driver, insulated gate bipolar transistor(IGBT), load current, robustness, temperature.

I. INTRODUCTIONNSULATED gate bipolar transistors (IGBTs) have been
widely employed in high-power applications due to theirhigh voltage/current capability and ease of driving. In a powersystem, the gate driver acts as the interface between low-voltage
control signals and power devices such as IGBTs. Therefore,
the gate driver has a direct impact on the switching behavior

I

Manuscript received 14 January 2023; revised 31 March 2023; accepted 16
May 2023. Date of publication 24 May 2023; date of current version 28 July
2023. This work was supported in part by the National Science and Technology
Council, Taiwan, under Grant 111-2636-E-A49-009 and in part by the Higher
Education Sprout Project of the National Yang Ming Chiao Tung University
and Ministry of Education, Taiwan. Recommended for publication by Associate
Editor A. Lindemann. (Corresponding author: Po-Hung Chen.)Ting-Wei Wang and Po-Hung Chen are with the Institute of Electronics,
National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan (e-mail:twwang.ee06g@nctu.edu.tw; hakko@nycu.edu.tw).
Toshiaki Inuma and Makoto Takamiya are with the Institute of Industrial
Science, The University of Tokyo, Tokyo 153-8505, Japan (e-mail: inuma@
iis.u-tokyo.ac.jp; mtaka@iis.u-tokyo.ac.jp).
Color versions of one or more figures in this article are available athttps://doi.org/10.1109/TPEL.2023.3279674.
Digital Object Identifier 10.1109/TPEL.2023.3279674

Fig. 1.

Example of GV.

of IGBTs. Conventional gate drivers (CGDs) adopt fixed gate
drive voltage and fixed gate resistance to control the charging
of the IGBT’s gate capacitance throughout entire switching
periods. Generally, the gate drive voltage or resistance is selected to meet requirements such as switching loss, overshoots
and electromagnetic interference. Unfortunately, CGD cannot
achieve a compromise between these conflicting objectives simultaneously. To overcome the drawback of CGD, many worksof active gate driver (AGD) have been proposed [1], [2], [3],[4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15],[16], [17], [18], [19], [20], [21], [22], [23], [24], [25], [26],[27], [28], [29], [30], [31], [32], [33], [34], [35], [36], [37],[38], [39]. Active gate driving of power devices, where the gate
driving current is dynamically controlled during the turn-ON/OFF
transients, is a solution to solve the trade-off between the switching loss (ELOSS ) and the current overshoot (IOVERSHOOT )or the voltage overshoot (VOVERSHOOT ) of CGD. The AGD
technique reported in [2], [3], [4], and [5] is composed of a
fixed voltage source and switched resistors to control the gatecharging current. Multilevel AGDs are introduced in [6], [7], [8],[9], and [10]. The gate driving voltage is changed at different
stages during the switching transients. Analog controller-based
current source presented in [11], [12], [13], [14], and [15] is acommon method for gate driving current adjustment in AGD.
In addition, active gate driving can also be realized by a digital
gate driver [16], [17], [18], [19], [20], [21], [22], [23], [24],[25], [26], [27], [28], [29], [30], [31], [32], [33], [34], [35],[36], [37], [38], [39] as the gate driving current of a digital
gate driver is programmable with gate driving vectors (GVs).
As depicted in Fig. 1, GV represents the gate driving pattern

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10670Fig. 2.

IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 38, NO. 9, SEPTEMBER 2023

Concept of RGV.

of a digital gate driver. GV is composed of several steps n andtheir durations t, where the gate charging/discharging current is
positively correlated to the magnitude of n. For example, a 6-b
programmable digital gate driver with four 6-bit variables for
IGBT is proposed in [16]. The optimum GV is automaticallyfound out of 644 (∼1.7 × 107 ) combinations by more than 2000
measurements using a simulated annealing (SA) algorithm. As aresult, the ELOSS is reduced by 55% at the same VOVERSHOOT ,and the VOVERSHOOT is reduced by 53% at the same ELOSS
at the turn-OFF of IGBT. However, the optimum GV varies
depending on operating conditions such as temperature and load
current (ILOAD ) [17]. When an optimum GV at a particulartemperature and ILOAD is reused to another temperature and
ILOAD , the ELOSS and IOVERSHOOT /VOVERSHOOT of IGBT
are sometimes worse than the conventional single-step gate
drive [17]. Therefore, robust gate driving vectors (RGV) against
temperature and ILOAD variations are required to solve theproblem [18].
The concept of RGV is illustrated in Fig. 2. The
object function (fOBJ ) is a function of ELOSS and
IOVERSHOOT /VOVERSHOOT of IGBT during turn-ON/OFF transient. The fOBJ is used to estimate the performance in the SA
algorithm [19]. A smaller fOBJ shows better performance on
ELOSS and IOVERSHOOT /VOVERSHOOT . RGVs are universal
GVs that can be applied to different operating conditions. Although RGV may not have an outstanding fOBJ under a specificoptimization condition, it reduces the maximum fOBJ acrossdifferent operating conditions. Take the two GVs in Fig. 2 forexample, the fOBJ, MAX˙A is lower than the fOBJ, MAX˙B , whichindicates that the gate vector A has better robustness than thegate vector B. From a practical viewpoint, product specifications are often determined by the maximum fOBJ , which makes
minimizing the maximum fOBJ across variations in operating
conditions important. However, the test cost of searching for
an RGV is very high. In [18], 90 000 measurements for a fullsearch of GVs across nine different temperature and ILOAD are
required to search an RGV, which take more than 5.5 h. To
reduce the test cost, robust simulated annealing (RSA) for an
automatic search method of RGV against temperature variation
is described in [20]. Nonetheless, RGV against ILOAD variation
is not included.

Fig. 3.

Circuit schematic of measurement setup.

In this article, search methods of RGVs with low test costs areproposed. Different types of GVs are chosen for RGV in turn-ON
and turn-OFF states. Compared with the conventional full searchmethod of RGV [18] and RSA [20], the proposed search methodof RGV has the lowest test cost. Moreover, when the searched
RGV and the optimum GV at single condition are both reused toother temperature and ILOAD conditions, the maximum overall
fOBJ of RGV is lower than that of the single condition optimum
GV, demonstrating the stronger robustness of the searched RGV.
The other sections of this article are organized as follows.
The proposed RGV search methods for turn-ON and turn-OFF are
introduced in Section II. In Section III, the measurement results
are shown. Section IV describes the comparison between the
proposed RGV and previous works. Finally, Section V presents
the conclusion drawn from this article.
II. RGV SEARCH METHOD
In this section, the measurement setup and different typesof GVs are introduced. Then, the single-step GV and the stopand-go GV in both turn-ON and turn-OFF states are discussed.
Furthermore, the proposed search methods of RGV for turn-ON
and turn-OFF are described in detail, respectively.
A. Measurement Setup and Gate Driving Vector
Fig. 3 shows a circuit schematic of the double pulse test
measurement setup for the turn-ON and turn-OFF of IGBT at
300 V. The measurement system consists of a 6-b programmabledigital gate driver [19], a 2-in-1 IGBT module (2MBI100TA060- 50, 600 V, 100 A), and a signal acquisition/control system.
In order to realize a programmable 63-level drivability in the
programmable digital gate driver, 63 parallel transistors areconnected to the gate of IGBT, and a 6-bit control signal isapplied to specify the number of activated PMOS (NMOS)
transistors, nPMOS (nNMOS ) [19].
Fig. 4 shows the GVs and waveforms for turn-ON state in the
6-bit digital gate driver. Fig. 4(a) shows the single-step GV and
Fig. 4(b) shows the stop-and-go GV. The single-step GV can be
expressed as (n), where n is an integer from 1 to 63. In order toincrease the gate charge resolution of conventional stop-and-go
GV [21] in a specific range, n1 is fixed to 25, and thereby n2 is

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WANG et al.: SEARCH METHOD OF ROBUST GATE DRIVING VECTORS FOR DIGITAL GATE DRIVERSfOBJ_OFF =

10671

ELOSS
ELOSS, MAX

2


+

VOVERSHOOT2

VOVERSHOOT, MAX(2)

where the subscript MAX signifies the maximum of the corresponding quantity. The ELOSS, MAX , IOVERSHOOT, MAX , and
VOVERSHOOT, MAX terms in (1) and (2) are determined by
the measured results of single-step GVs, which are labeled in
Figs. 12 and 13.
In this article, to explain the proposed RGV search method,
ELOSS and IOVERSHOOT /VOVERSHOOT of IGBT are measured
across nine conditions, including different ILOAD (20 A, 50 A,
80 A) and temperature (25 °C, 75 °C, 125 °C).
B. Proposed Search Method of Robust Single-Step GV in
Turn-ON
Fig. 4. GVs and waveforms in turn-ON state. (a) Single-step gate drive.
(b) Stop-and-go gate drive.

Fig. 5. GVs and waveforms in turn-OFF state. (a) Single-step gate drive.
(b) Stop-and-go gate drive.

the only variable. Thus, the stop-and-go GV for turn-ON in thisarticle is defined as (25, n2 , 0, 63), where n2 is an integer from0 to 63.
Fig. 5 shows the GVs and waveforms for turn-OFF state in
the 6-b digital gate driver. Fig. 5(a) shows the single-step GV,
and Fig. 5(b) shows the stop-and-go GV. The single-step GV
can be expressed as (n), where n is an integer from 1 to 63. The
purpose of Fig. 5(b) is the same as Fig. 4(b), which is for higher
gate charge resolution. Thus, the stop-and-go GV for turn-OFF
in this article is defined as (39, n2 , 0, 63), where n2 is an integer
from 0 to 63. The selection of n1 , t1 and t3 in stop-and-go GVof turn-ON and turn-OFF states are described in [21]. The t2 is
set 10% of the total duration of t1 and t2 .
To evaluate the performance of a GV, the turn-ON object
function (fOBJ_ON ) and turn-OFF object function (fOBJ_OFF ) aredefined as

2 
2
IOVERSHOOT
ELOSS
+
(1)
fOBJ_ON =ELOSS, MAX
IOVERSHOOT, MAX

Fig. 6(a) shows the measured fOBJ versus n with single-step
GV at nine different ILOAD and temperature conditions in turnON state. Fig. 7(a) shows the measured fOBJ versus n2 withstop-and-go GV at nine conditions in turn-ON state. The target
is to search for a single n/n2 with the lowest maximum fOBJ .
Comparing the maximum fOBJ curve of two GVs in Figs. 6(b)and 7(b), single-step GV gives a lower maximum fOBJ , whichshows a better switching performance. Therefore, single-step
GV is selected as the type of RGV for turn-ON.
To search the robust single-step (RSS) GV (n), a worst-casesearch method is used. In Fig. 6(a), the case of 80 A, 125 °C
provides the largest fOBJ s among almost all different n. In otherwords, the case of 80 A, 125 °C decides the maximum fOBJ of
the nine conditions with every single n, which shows that 80 A,
125 °C is the worst case of the nine conditions. Therefore, we
can search the RGV at 80 A, 125 °C instead of nine different
conditions. Then, n = 13 with the lowest fOBJ at 80 A, 125 °C
is found as the target RGV.
As stated above, single-step GV is chosen as the RGV type
for turn-ON. The proposed RSS GV search method is to search
the optimum n at the condition of largest ILOAD and highest
temperature. Therefore, only 63 measurements are required tosearch the RGV with the proposed search method, which results
in reduced test cost. If stop-and-go is selected as the RGV type,
test cost is increased to 567 (= 9 × 63) measurements.
C. Proposed Search Method of Robust Stop-and-Go GV in
Turn-OFF
Fig. 8(a) shows the measured fOBJ versus n with single-step
GV at nine different ILOAD and temperature conditions in turnOFF state. Fig. 9(a) shows the measured fOBJ versus n2 withstop-and-go GV at nine conditions in turn-OFF. Comparing the
maximum fOBJ curve of two GVs in Figs. 8(b) and 9(b), stopand-go GV gives a lower maximum fOBJ , which shows a better
switching performance. Hence, stop-and-go GV is more suitable
as the type of RGV for turn-OFF.
Fig. 10 shows the optimum n2 extracted from Fig. 9(a) at
nine different ILOAD and temperature conditions. As the ILOAD
increases, n2 slightly reduces. As the temperature increases, n2
increases significantly. Therefore, n2 shows both ILOAD and

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10672IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 38, NO. 9, SEPTEMBER 2023

Fig. 6.

Single-step gate drive in turn-ON state. (a) fOBJ versus n of nine conditions. (b) Maximum fOBJ vs. n.

Fig. 7.

Stop-and-go gate drive in turn-ON state. (a) fOBJ versus n2 of nine conditions. (b) Maximum fOBJ vs. n2 .

Fig. 8.

Single-step gate drive in turn-OFF state. (a) fOBJ versus n of nine conditions. (b) Maximum fOBJ versus n.

temperature correlation. The four corner conditions are definedas (the smallest and largest ILOAD ) × (the lowest and highest
temperature). The results of the four corner conditions include
that of the nine conditions. Fig. 11 shows the maximum fOBJ
curve at four corner conditions, similar to Fig. 9(b).
From Fig. 9(a), for any condition, when n2 is smaller than the
optimum value, the fOBJ increases significantly, which indicatesworse switching performances of ELOSS and VOVERSHOOT . In

other words, the targeting region is where n2 is larger than the
optimum value.
As stated above, a search method of robust stop-and-go(RSNG) GV for turn-OFF is proposed. There are two steps inthe search method introduced in the following.
1) Search optimum n2 under each corner condition of ILOAD
and temperature. Since n2 shows both ILOAD and temperature correlation, the searching range can be set toAuthorized licensed use limited to: University of Tokyo. Downloaded on October 07,2023 at 13:20:29 UTC from IEEE Xplore. Restrictions apply.

WANG et al.: SEARCH METHOD OF ROBUST GATE DRIVING VECTORS FOR DIGITAL GATE DRIVERS

Fig. 9.

10673

Stop-and-go gate drive in turn-OFF state. (a) fOBJ versus n2 of nine conditions. (b) Maximum fOBJ versus n2.

Fig. 10. Optimum n2 of stop-and-go gate drive across nine conditions including different ILOAD and temperature.

Fig. 11. Maximum fOBJ versus n2 of stop-and-go gate drive in turn-OFF state
at four corner conditions.

corner condition instead of full search under all operating
conditions.
2) Choose the largest optimum n2 from four corner conditions as the target n2 and thus the RSNG GV is found.
The reason for choosing the largest n2 is to make sure thatthe chosen n2 is in the target region of other operating
conditions.
By using the proposed search method, a largest n2 = 35 canbe found at 20 A, 125 °C, and therefore the RSNG GV for
turn-OFF is searched. A total of 256 (= 4 × 64) measurements
are required to search the RGV with the proposed search method,which results in reduced test cost.
III. MEASURED RESULTS
In order to clarify that the RGVs from the proposed searchmethod are effective in providing smaller maximum fOBJ s,

ELOSS and IOVERSHOOT /VOVERSHOOT of IGBT are measured
across nine conditions including different ILOAD (20 A, 50 A,
80 A) and temperature (25 °C, 75 °C, 125 °C). Fig. 12 shows themeasured ELOSS versus IOVERSHOOT of different gate drives inturn-ON state, while Fig. 13 shows the measured ELOSS versus
VOVERSHOOT in turn-OFF state. The black curves show thetradeoff of the single-step gate drive with varied n from 4 to
63. The black circles show the RSS gate drive searched with theproposed search method, where n = 13 in turn-ON state. The
blue curves show the results of the stop-and-go gate drive withvaried n2 from 0 to 63. The blue circles show the RSNG GV
searched with the proposed search method, where n2 = 35 in
the turn-OFF state. The red circles show the reuse of optimum
stop-ang-go GV at 50 A, 75 °C. The dotted concentric curves
show the contour of fOBJ_ON and fOBJ_OFF defined in (1) and(2), respectively. The fOBJ s of the abovementioned gate drives
at nine conditions in turn-ON and turn-OFF state are respectively
plotted in Fig. 14(a) and (b). The maximum fOBJ s of the RGVs
with the proposed search method are the lowest, which indicatesthat the concept of robustness is realized.
A. Turn-ON
Fig. 15(a)–(c) show the GVs and the measured waveforms
in turn-ON state at 50 A, 75 °C of the RSS GV (n = 13), the
RSNG GV (n2 = 37) and the optimum stop-and-go GV (n2 =31), respectively. The optimum stop-and-go GV gives the best
switching performance among the three different GVs.
Fig. 16(a)–(c) show the GVs and the measured waveforms
in turn-ON state at 80 A, 125 °C of the RSS GV (n = 13), the
RSNG GV (n2 = 37) and the reuse of optimum stop-and-go GV(n2 = 31) at 50 A, 75 °C, respectively. As clearly shown in theextracted result from Fig. 14(a), the proposed RSS GV gives thelowest maximum fOBJ across the nine conditions. In contrast,
the reuse of stop-and-go GV gives a larger fOBJ than the RGVs.
Therefore, the reuse of an optimum GV is not robust to ILOAD
and temperature variations.
B. Turn-OFF
Fig. 17(a)–(c) show the GVs and the measured waveforms
in turn-OFF state at 50 A, 75 °C of the RSS GV (n = 6),

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10674IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 38, NO. 9, SEPTEMBER 2023

Fig. 12. Measured ELOSS versus IOVERSHOOT of different gate drives in turn-ON state. Black curves: tradeoff curves of single-step gate drive with varied n.
Blue curves: results of stop-and-go gate drive with varied n2 . Black circles: proposed robust single-step gate drive (RSS). Blue circles: robust stop-and-go (RSNG)
gate drive. Red circles: reuse of optimum stop-and-go GVs at 50 A, 75 °C (SNG reuse).

the RSNG GV (n2 = 35) and the optimum stop-and-go GV(n2 = 27), respectively. The optimum stop-and-go GV gives
the best switching performance among the three different
GVs.
Fig. 18(a)–(c) show the GVs and the measured waveforms inturn-OFF state at 20 A, 125 °C of the RSS GV (n = 6), the RSNG
GV (n2 = 35) and the reuse of optimum stop-and-go GV (n2 =27) at 50 A, 75 °C, respectively. As clearly shown in the extracted
result from Fig. 14(b), the reuse of stop-and-go GV gives a larger
fOBJ than the RGVs. Therefore, the reuse of an optimum GV
is not robust to ILOAD and temperature variations. As shown in
Fig. 14(b), the proposed RSNG GV gives the lowest maximum

fOBJ across the nine conditions, which shows that the proposed
RGV is effective to both ILOAD and temperature variations.
IV. DISCUSSION
Different search methods and different types of RGVs were
proposed in [18] and [20]. In this section, the test cost andperformance of the proposed RGVs are discussed and comparedwith previous RGV works.
In [18], a full search across nine conditions is used to findthe RGV. The GV is defined as (n1 , n2 , n3 , n4 ). To reduce the
combinations of GV, the levels of n1 , n2 , n3 and n4 are reduced

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WANG et al.: SEARCH METHOD OF ROBUST GATE DRIVING VECTORS FOR DIGITAL GATE DRIVERS

10675

Fig. 13. Measured ELOSS versus VOVERSHOOT of different gate drives in turn-OFF state. Black curves: tradeoff curves of single-step gate drive withvaried n. Blue curves: results of stop-and-go gate drive with varied n2 . Black circles: robust single-step gate drive (RSS). Blue circles: proposed robust stop-and-go(RSNG) gate drive. Red circles: reuse of optimum stop-and-go GVs at 50 A, 75 °C (SNG reuse).

from 64 to 10. As a result, the required measurements for a
full search in a single condition are reduced from 644 to 104 . In
total, the 90 000 (= 9 × 104 ) measurements across nine different
conditions take about 5.5 hours. From the measured results, themaximum fOBJ s of the RGVs across nine conditions in turn-ON
and turn-OFF state are, respectively, around 0.7 and 0.75.
In [20], a search method of RSA is proposed. Temperature
variation is emulated by gate driving current variation, which isrealized by adding Δ into GV. The GV becomes (n1 +Δ, n2 +Δ,
n3 +Δ, n4 +Δ) where Δ is 0 or 1, in total 16 (= 24 ) combinations.
An inner loop which is repeated 16 times is added into the SA
iteration. Therefore, RGV is searched under a single condition

by RSA. It takes about 50 min to search RGV by repeating about
2500 optimization loops (= 2500 × 16 = 40 000 measurements).
From the measured results, the maximum fOBJ_OFF acrossdifferent temperature conditions is around 1. However, only
temperature variation in turn-OFF state is discussed.
In this article, 63 and 256 (= 4 × 64) measurements are required to search RGVs in turn-ON and turn-OFF states, which takeless than 1 and 4 min, respectively. From the measured results,
the maximum fOBJ_ON and fOBJ_OFF are 0.75 and 0.87, whichshow great robustness of RGV from the proposed search method.
The comparison between search methods and the performancesof different RGVs is given in Table I. Compared with the full

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10676

Fig. 14.

IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 38, NO. 9, SEPTEMBER 2023

fOBJ of three gate drives at nine conditions. (a) Turn-ON state. (b) Turn-OFF state.

Fig. 15. GVs and measured waveforms at 50 A, 75 °C in turn-ON state. (a) Proposed robust single-step gate drive. (b) Robust stop-and-go gate drive. (c) Optimum
stop-and-go gate drive.

Fig. 16. GVs and measured waveforms at 80 A, 125 °C in turn-ON state. (a) Proposed robust single-step gate drive. (b) Robust stop-and-go gate drive. (c) Reuseof optimum stop-and-go gate drive at 50 A, 75 °C.

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WANG et al.: SEARCH METHOD OF ROBUST GATE DRIVING VECTORS FOR DIGITAL GATE DRIVERS

10677

Fig. 17. GVs and measured waveforms at 50 A, 75 °C in turn-OFF state. (a) Robust single-step gate drive. (b) Proposed robust stop-and-go gate drive (c) Optimum
stop-and-go gate drive.

Fig. 18. GVs and measured waveforms at 20 A, 125 °C in turn-OFF state. (a) Robust single-step gate drive. (b) Proposed robust stop-and-go gate drive. (c) Reuseof optimum stop-and-go gate drive at 50 A, 75 °C.

TABLE ICOMPARISON OF STATE-OF-THE-ART RGV SEARCHMETHOD AND PERFORMANCEThe searched RGVs in this article are effective to ILOAD andtemperature variations. However, when the IGBT’s thresholdvoltage varies due to manufacturing variations, research of RGV
is required.
V. CONCLUSION

search method of RGV [18], although the maximum fOBJ_ON
and fOBJ_OFF are slightly larger, the test cost is greatly reduced
by 99%. Compared with RSA [20], not only the maximum fOBJ
is lower, but also the test cost can be reduced by 92%.

The test cost of searching RGV against variation in operating
conditions is very high. In this article, RGV search methods forboth turn-ON and turn-OFF states are proposed to reduce the test
cost of searching RGV. In the switching measurements of IGBT
at 300 V across the nine operating conditions including different
ILOAD (20 A, 50 A, 80 A) and temperature (25 °C, 75 °C,
125 °C), maximum fOBJ_ON and fOBJ_OFF of the searched RGV
are 0.75 and 0.87, respectively. Compared with previous worksof RGV search methods in [18] and [20], the proposed searchmethod reduces the test cost by 99% and 92% while providing
a moderate fOBJ .

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10678IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 38, NO. 9, SEPTEMBER 2023

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Ting-Wei Wang (Student Member, IEEE) received
the B.S. degree in electronic engineering from National Chiao Tung University, Hsinchu, Taiwan, in
2017. He is currently working toward the Ph.D. degree in electronic engineering with National Yang
Ming Chiao Tung University, Hsinchu.
His research interest includes gate driver integrated
circuit for wide-bandgap power devices.

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WANG et al.: SEARCH METHOD OF ROBUST GATE DRIVING VECTORS FOR DIGITAL GATE DRIVERS

Toshiaki Inuma received the B.S degree in electronics and communication engineering from Musashi
Institute of Technology, Tokyo, Japan in 1983.
He was with Headquarters Technology Development Department, Hitachi Transport System, Ltd.
from 1984 to 2015. He is qualified for Professional
Engineer, Japan (electrical/electronics, industrial engineering) and the first-class radio engineer in Japan.
Since 2020, he has been a Project Academic Specialist
with the University of Tokyo. His research interest
includes measurement of digital gate driver circuits
for power electronics.

Po-Hung Chen (Senior Member, IEEE) received the
M.S. degree in electronic engineering from National
Chiao Tung University, Hsinchu, Taiwan, in 2007,
and the Ph.D. degree in electrical engineering fromThe University of Tokyo, Tokyo, Japan, in 2012.
In 2011, he was a Visiting Scholar with the University of California at Berkeley, Berkeley, CA, USA,
where he conducted research in fully integrated power
management circuits for RISC-V processors. He iscurrently a Professor with the Institute of Electronics,
National Yang Ming Chiao Tung University, Hsinchu,
Taiwan. His research focuses on power management integrated circuits, with a
special emphasis on energy harvesting, battery management, battery charger,
and wireless power transmission.
Dr. Chen has been a Technical Program Committee Member of the IEEE
Symposium on VLSI Circuits since 2020 and the IEEE Asian Solid-State
Circuits Conference since 2016. He was the TPC Vice-Chair of A-SSCC 2020
and a Guest Editor for IEEE JOURNAL OF SOLID-STATE CIRCUITS. He is also theVice Chair of the IEEE Solid-State Circuits Society Taipei Chapter.

10679

Makoto Takamiya (Senior Member, IEEE) received
the B.S., M.S., and Ph.D. degrees in electronic engineering from the University of Tokyo, Japan, in 1995,
1997, and 2000, respectively.
In 2000, he was with NEC Corporation, Japan,
where he was engaged in the circuit design of highspeed digital LSI’s. In 2005, he was with the University of Tokyo, Tokyo, Japan, where he is currently
a Professor with the Institute of Industrial Science.
From 2013 to 2014, he was a Visiting Scholar with
the University of California, Berkeley, CA, USA. His
research interests include the digital gate driver and sensor ICs for powerelectronics and the integrated power management circuits for automotive andindustrial applications.
Dr. Takamiya is a member of the technical program committee of IEEE
Symposium on VLSI Circuits and IEEE Asian Solid-State Circuits Conference.
He formerly served on the technical program committees of IEEE International
Solid-State Circuits Conference (ISSCC) from 2015 to 2020 and IEEE Custom
Integrated Circuits Conference from 2006 to 2011. He was a Far East Regional
Chair in ISSCC 2020. He was a Distinguished Lecturer of IEEE Solid-State
Circuits Society from 2019 to 2020. He was the recipient of 2009 and 2010
IEEE Paul Rappaport Awards and the best paper award in 2013 IEEE WirelessPower Transfer Conference.

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