Proceedings of The 29th International Symposium on Power Semiconductor Devices & ICs, Sapporo

1-2Power Electronics 2.0:
IoT-Connected and AI-Controlled Power Electronics
Operating Optimally for Each User
Makoto Takamiya1, Koutaro Miyazaki1, Hidemine Obara2, 3, Toru Sai1, Keiji Wada2, and Takayasu Sakurai1
University of Tokyo, Tokyo, JapanTokyo Metropolitan University, Tokyo, Japan
3Yokohama National University, Yokohama, Japan
12

Abstract—The emerging trend of internet of things (IoT) andartificial intelligence (AI) technologies will bring about a majorchange in power electronics and create a new generation of thepower electronics (Power Electronics 2.0). To enable the IoT- andAI-assisted Power Electronics 2.0, the integration of the sensors,
the programmable hardware, and VLSIs for the controller into
the power devices/modules is very important. In this paper, a 6bit programmable gate driver IC with automatic optimization ofgate driving waveform for IGBT is presented as the first step
toward Power Electronics 2.0. In the proposed gate driver, the 6bit gate control signals with four 160-ns time steps are globally
optimized using a simulated annealing algorithm, reducing thecollector current overshoot by 37% and the switching loss by
47% at the double pulse test of 300V, 50A IGBT. The gate driveris also applied to a half-bridge inverter, where the gate driving
waveform is changed depending on the load current.

User 2

Ready-madepower devices(a) Power Electronics 1.0

Power device
manufactures
 Big data
 AIIoT

User 1
Power devices including Sensors

Managed Programmable
by VLSIs
hardwareUser 2

Keywords—IoT, AI, power electronics, programmable, gate
driver, IGBTI.

User 1

Power device
manufactures(b) Power Electronics 2.0

INTRODUCTION

Fig. 1. (a) Conv. Power Electronics 1.0. (b) New Power Electronics 2.0.

The emerging trend of internet of things (IoT) and artificial
intelligence (AI) technologies will bring about a major change
in power electronics and create a new generation of the powerelectronics (Power Electronics 2.0). Fig. 1(a) shows aconventional power electronics (Power Electronics 1.0).
Ready-made power devices are provided from the powerdevice manufacturers to the power device users. The powerdevice manufacturers do not know the real usage conditions of
the power devices of each user. Each power device user has nochoice but to use the ready-made power devices, which resultsin the mismatch between the user’s real requirements and thespecification of the ready-made power devices. IoT and AI
technologies will fill the gap between the power device
manufacturers and the power device users. Fig. 1(b) shows theproposed Power Electronics 2.0. In IoT area, by embedding awide variety of massive sensors into the powerdevices/modules and transmitting the measured data to thepower device manufacturers through the Internet, the powerdevice manufacturers and the power device users are directlyconnected and the power device manufacturers can monitor
real operating conditions of the power devices for each user. In
AI area, by analyzing the big sensor data from multiple users
using AI, the power device manufacturers can provide
customer-tailored services for each user, which provides new

business opportunities to the power device manufacturers. Eachpower device user can enjoy the customer-tailored service andthe power devices operate optimally for each user by tuning theparameters in the programmable hardware with digitalinterfaces. To enable the IoT- and AI-assisted PowerElectronics 2.0, the integration of the sensors, theprogrammable hardware, and VLSIs for the controller into thepower devices/modules is very important. In this paper, a 6-bit
programmable gate driver IC with automatic optimization ofgate driving waveform for IGBT is presented as the first step
toward Power Electronics 2.0. The gate driver IC is an
important circuit bridging the voltage gap between VLSIs
operating less than 5V and the power electronics operating
above 100V. In the proposed gate driver, the 6-bit gate control
signals with four 160-ns/400-ns time steps are globally
optimized using a simulated annealing algorithm. The gate
driver is also applied to a half-bridge inverter, where the gate
driving waveform is changed depending on the load current.
II.

TRADE-OFF IN GATE DRIVERS FOR IGBT

Gate driving waveform optimization of power devices for
reducing energy loss without inducing large current or voltage

29

VDC=300V
Large RG

Turn-onsignalICVGE

IOVERSHOOTIGBTGate driver
VDC=300V

VGETimeELOSS
Temporal reduction of IGIOVERSHOOT
ICVCE
VGE

Time

ELOSS

Fig. 4. Trade-off between ELOSS and IOVERSHOOT at turn-on of IGBT.

IG

Implemented on a chipIC

Level-shifters& Buffers B2T*

VDRIVE(15V)

VCE

VGE

6BPMOSVDRIVE -VPD_PMOS

63 NMOSs

BPMOS
5V
CK
logic
BNMOS

6663
GPMOS

IC

VG

6363
DQ
nNMOS

VC

IG

63
GNMOS

CK

1

GND

VDC=300V

63-Parallel
Drivers

CK

6BNMOS

1Predriver

D-FF

63
63
DQ
n PMOS

1VPD_NMOS*) B2T: Binary to Thermometer-code decoder

Fig. 3. Proposed programmable gate driver with digital control signals forIGBT.

Fig. 5. Circuit schematic of the proposed programmable gate driver IC.

n1n2n3 n4t

n1 n n3 n2n0=0n=634t

VGEn0=0n=63VGEnPMOSovershoot has been attracting attention [1-7]. Fig. 2 shows aconventional gate driver with a gate resistor (RG) for IGBT. Fig.
3 shows the proposed programmable gate driver with digital
control signals for IGBT [8]. In order to realize programmable63-level drivability, 63 parallel drivers are connected to thegate of IGBT and a 6-bit binary control signal is applied tospecify the number of activated PMOS (NMOS) drivertransistors. Fig. 4 show a trade-off between the switching loss(ELOSS) and the collector current overshoot (IOVERSHOOT) at theturn-on of IGBT. In the conventional gate driver, ELOSS andIOVERSHOOT are the trade-off, because large ELOSS and small
IOVERSHOOT is obtained at large RG, while small ELOSS and large
IOVERSHOOT is obtained at small RG. In contrast, in the proposed
programmable gate driver, the trade-off is solved by temporally
reducing the gate current (IG) using the programmable IG toreduce IOVERSHOOT. Therefore, the precise control of IG with afine timing resolution is required.
III.

IC

VTH

Proposedprogrammablegate driver
15V 63 PMOSs

Turn-onsignal&Digitalcontrolsignals(6bit x 2)

VTH

Proposedprogrammablegate driverFig. 2. Conventional gate driver for IGBT.

IOVERSHOOT

VCE

Small RG

VCE

Time

ELOSS

nNMOS

RG IG

VGE

VTH
Conv.
gate driver

ELOSS

IL
15V

IOVERSHOOTIC

VCE

IOVERSHOOT
VCEt
ICt
TSTEP = 160ns
4 time-segments(a)Turn-on of IGBTICt
VOVERSHOOT
VCEtTSTEP = 400ns
4 time-segments(b)Turn-off of IGBT

Fig. 6. Schematic of gate driving waveforms. (a) Turn-on. (b) Turn-off.

bit signals (BPMOS and BNMOS) are latched by the clock (CK)
and activate the final 63 PMOS (NMOS) transistors. Fig. 6
shows a schematic of gate driving waveforms with 4 timesegments. The programmable gate driver IC accepts a sequenceof nPMOS and a sequence of nNMOS as the control inputs andchanges the output drivability accordingly. Any strength ofdrivability from 0 to 63 (x 12-mA for both of PMOS andPROGRAMMABLE GATE DRIVER ICFig. 5 shows a circuit schematic of the proposed
programmable gate driver IC [8]. A 6-bit binary control signal,BPMOS (BNMOS), is applied to specify the number of activated
PMOS (NMOS) driver transistors, nPMOS (nNMOS). A pair of 6-30

NMOS) can be chosen for each of the 4 time-segments, that is,n1, n2, n3, and n4 in Fig. 6 can be any of integers from 0 to 63.
The time step (TSTEP) is set to 160ns and 400ns for turn-on andturn-off of IGBT, respectively. A programmable gate driver IC
with 150-ps TSTEP and 15-bit control is also reported for the fastswitching GaN power devices [9-10].

f OBJECT(ON)  ELOSS2  IOVERSHOOT 2 2
f OBJECT(OFF)  ELOSS2  VOVERSHOOT

IV.

NMOSdrivers

PMOSdrivers

Programmablegate driver ICDigital I/Os
IGBT module(600V, 100A)fOBJECT(ON) = 1.20 1
0 0.2 0.4 0.6 0.8 1Time (μs)

5Conv.

40.4
20Single-step drive

800 0.2 0.4 0.6 0.8 1Time (μs)

-47%0.2

6300 0.2 0.4 0.6 0.8 1
Time (μs)

-37%

0.1

ELOSS, NIN

Turn-onSingle-step drive

0.50.3

100.8
0.7

nPMOS

Optimized

5223 16200 0.2 0.4 0.6 0.8 1
Time (μs)

1.0
0.9

0.6

363

1.3

1.1

nPMOS

ProposedSingle-step drive

6nPMOSELOSS, NAX
ELOSS (mJ)

Fig. 7. Photo of developed programmable gate driver attached on IGBTmodule.

nPMOS

where ' signifies the normalized quantity and the subscript MIN(MAX) signifies the minimum (maximum) of thecorresponding quantity. For example, ELOSS,MIN is the measured
ELOSS when the gate driving waveform is the fastest, that is, allof n1, n2, n3, n4, and n∞ are 63. On the other hand, ELOSS,MIN is
the measured ELOSS when the gate drive waveform is theslowest, that is, all of n1, n2, n3, n4, and n∞ are 1. After thenormalization, all of the normalized quantities vary between 0
and 1. The object functions (fOBJECT(ON) for turn-on of IGBT andfOBJECT(OFF) for turn-off of IGBT) to be minimized in theoptimization using the simulated annealing is set as below.

B2T+DFF+Predriver

730μm

In the waveform optimization process, 644 (~1.7 x 107)
different waveforms need to be tried for an exhaustive search,which is impractical. The machine-based optimization using
the simulated annealing algorithm [11] is proposed to make theoptimization practical. The details of the automatic
optimization method is shown in [12]. The objective is toreduce ELOSS and IOVERSHOOT for the turn-on case (the overshootof VCE, VOVERSHOOT, for the turn-off case). In order to achieve
this goal, at first, the energy loss and the overshoot values arenormalized as below.
E LOSS  E LOSS,MINE 'LOSS E LOSS,MAX  E LOSS,MINIII 'OVERSHOOT  OVERSHOOT OVERSHOOT,MIN IOVERSHOOT,MAX  IOVERSHOOT,MIN
VOVERSHOOT  VOVERSHOOT,MINV 'OVERSHOOT VOVERSHOOT,MAX  VOVERSHOOT,MIN

2300μm

51015202530IOVERSHOOT (A)IOVERSHOOT, MIN

3540IOVERSHOOT, MAXFig. 8. Measured ELOSS and IOVERSHOOT at turn-on of IGBT.
VCE : 50V/div
IC : 10A/div
VGE : 5V/div

Same ELOSSVCEMEASURED IGBT SWITCHINGVCEICVGE

VGEnPMOS

Fig. 7 shows a photo of the developed programmable gatedriver PCB attached on an IGBT module (600V, 100A rating).
The proposed programmable gate driver IC is fabricated with40V, 0.18μm BCD process. The core size is 2300μm by 730μm.
Both turn-on and turn-off characteristics of IGBT are measured
with a 300-V double-pulse setup with the load current of 50A.

1005000The proposed automatically optimized gate waveforms arecompared with the conventional single-step gate waveforms.
Fig. 8 shows the measured ELOSS and IOVERSHOOT of theconventional single-step gate waveforms and the proposed
automatically optimized gate waveforms at the turn-on ofIGBT. The dotted concentric curves show the contour offOBJECT(ON) defined in Eq. (4). ELOSS, MAX and ELOSS, MIN in Eq.
(1) and IOVERSHOOT, MAX and IOVERSHOOT, MIN in Eq. (2) are shownin Fig. 8. In the conventional single-step gate waveforms, ELOSS
and IOVERSHOOT are the trade-off. In contrast, the proposed
automatically optimized gate waveform solves the trade-off.
Compared with the conventional waveforms, the proposed

080.2

0.4

0
0.6

0.8

IC

1.0Time (μs)

1.2(a) Single-step drive(Conventional)

1.4

1.6 0160ns23 16
0.20.452 632
0.6

0.8

1.0Time (μs)

1.2

1.4

1.6(b) Optimized gate drive(Proposed)

Fig. 9. Measured waveforms at turn-on of IGBT.

waveform reduces ELOSS by 47% at the same IOVERSHOOT andIOVERSHOOT by 37% at the same ELOSS. The latter measured
waveforms are shown in Fig. 9. The similar results are obtainedin the turn-off of IGBT. Fig. 10 shows the measured ELOSS andVOVERSHOOT of the conventional single-step gate waveforms
and the proposed automatically optimized gate waveforms at
the turn-off of IGBT. The dotted concentric curves show thecontour of fOBJECT(OFF) defined in Eq. (5). ELOSS, MAX and ELOSS,

31

MIN in Eq. (1) and VOVERSHOOT, MAX and VOVERSHOOT, MIN in Eq.

V.

(3) are shown in Fig. 10. Compared with the conventional
waveforms, the proposed waveform reduces ELOSS by 55% at
the same VOVERSHOOT and VOVERSHOOT by 53% at the same
ELOSS. The latter measured waveforms are shown in Fig. 11.

As the first step toward Power Electronics 2.0, the 6-bit
programmable gate driver IC with automatic optimization ofgate driving waveform for IGBT is presented. Compared withthe conventional single-step gate waveforms, the proposed
automatically optimized gate waveform reduces ELOSS by 47%
at the same IOVERSHOOT and IOVERSHOOT by 37% at the same
ELOSS at the turn-on of IGBT, and reduces ELOSS by 55% at thesame VOVERSHOOT and VOVERSHOOT by 53% at the same ELOSS atthe turn-off of IGBT.

The programmable gate driver IC is also applied to a halfbridge inverter, where the gate driving waveform is changed
depending on the load current [13]. Compared with theconventional single-step gate waveforms, the active gatecontrol increases the efficiency of the half-bridge inverter at thesame surge voltage [13].

ACKNOWLEDGMENT

Single-step drive

nNMOS

00 0.2 0.4 0.6 0.8 1 1.0
Time (μs)
0.9100.80.6

nNMOS

Optimized
46
000.4
0.3ELOSS, NIN0 0.2 0.4 0.6 0.8 1Time (μs)

Conv.

-55%

50.2020

1.3

Turn-off

20
00 0.2 0.4 0.6 0.8 1
Time (μs)

Single-step drive
6300 0.2 0.4 0.6 0.8 1
Time (μs)

-53%
4060

80100

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1.1

0.1
0[1]

Single-step drive

0.7

0.5

6332

REFERENCES

nNMOS

Proposed55

fOBJECT(OFF) 1.2= 1.2
1This work was partly supported by NEDO.

nNMOSELOSS, NAX
ELOSS (mJ)The optimized parameters for the gate waveform depends
on multiple conditions including the load current, the operating
voltage, the temperature, and the variations of power devices.
Therefore, the parameters should be optimally changed
depending the operating conditions. How to change theparameters is the key point of the IoT- and AI-assisted PowerElectronics 2.0. When the power device manufacturers and thepower device users are not connected through the Internet, thefirst-step scenario will be to prepare multiple lookup tables
before shipment and to change the parameters based on thetables depending on the measured sensor data. When themanufacturers and the users are always connected through theInternet, the second-step scenario will be that themanufacturers determine optimal parameters using AI based on
the big data collected by IoT and transmit the parameters to theusers through the Internet as shown in Fig. 1(b).
15120140160180

VOVERSHOOT (V)200

VOVERSHOOT, MAX

VOVERSHOOT, MINFig. 10. Measured ELOSS and VOVERSHOOT at turn-off of IGBT.
VCE : 50V/div
IC : 10A/div
VGE : 5V/div

Same ELOSS
VCE

IC

VCE

IC

VGE

VGE

nNMOS

100
50000400ns

20
0.2

0.4

0.6

0.8

1.0

Time (μs)

1.2(a) Single-step drive(Conventional)

1.4

1.6 0055
0.2

4600.4

0.6

0.8

1.032
1.2

63
1.4

CONCLUSIONS

1.6Time (μs)(b) Optimized gate drive(Proposed)

Fig. 11. Measured waveforms at turn-off of IGBT.

32