Page Needham 21st Annual Growth Conference New York, New York January 15th, 2019 Exhibit 99.1

Page Safe Harbor Statement Any statements set forth herein that are not historical facts are forward-looking statements that involve risks and uncertainties that could cause actual results to differ materially from those in the forward-looking statements. Such forward-looking statements include, but are not limited to, statements regarding updates to Diodes Incorporated’s fourth quarter 2018 business outlook as of November 6, 2018, which include the following: expect revenue to be approximately $315 million, plus or minus 3 percent, or down 1.9 percent sequentially; expect GAAP gross margin to be 36.0 percent, plus or minus 1 percent; non-GAAP operating expenses, which are GAAP operating expenses adjusted for amortization of acquisition-related intangible assets, are expected to be approximately 21.0 percent of revenue, plus or minus 1 percent; expect net interest expense to be approximately $2.0 million; expect tax rate to be 29.5 percent, plus or minus 3 percent; shares used to calculate diluted EPS for the second quarter are anticipated to be approximately 52.2 million; purchase accounting adjustments for Pericom and previous acquisitions of $3.5 million after tax are not included in these non-GAAP estimates; and other statements identified by words such as “estimates,” “expects,” “projects,” “plans,” “will,” and similar expressions. Potential risks and uncertainties include, but are not limited to, such factors as: the risk that such expectations may not be met; the risk that the expected benefits of acquisitions may not be realized or that integration of acquired businesses may not continue as rapidly as we anticipate; the risk that we may not be able to maintain our current growth strategy or continue to maintain our current performance, costs, and loadings in our manufacturing facilities; the risk that we may not be able to increase our automotive, industrial, or other revenue and market share; risks of domestic and foreign operations, including excessive operation costs, labor shortages, higher tax rates, and our joint venture prospects; the risk that we may not continue our share repurchase program; the risks of cyclical downturns in the semiconductor industry and of changes in end-market demand or product mix that may affect gross margin or render inventory obsolete; the risk of unfavorable currency exchange rates; the risk that our future outlook or guidance may be incorrect; the risks of global economic weakness or instability in global financial markets; the risks of trade restrictions, tariffs, or embargoes; the risk of breaches of our information technology systems; and other information, including the “Risk Factors” detailed from time to time in Diodes’ filings with the United States Securities and Exchange Commission. This presentation also contains non-GAAP measures. See the Company’s press release on November 6, 2018 titled, “Diodes Incorporated Reports Third Quarter 2018 Financial Results” for detailed information related to the Company’s non-GAAP measures and a reconciliation of GAAP net income to non-GAAP net income.

Page Management Representative Dr. Keh-Shew Lu President and CEO Diodes IncorporatedSince 2005 Texas Instruments 27 years Experience: Senior Vice President of TI Worldwide Analog and Logic President of Texas Instruments – Asia Education: Master's Degree and Doctorate in Electrical Engineering Texas Tech University Bachelor's Degree in Engineering National Cheng Kung University - Taiwan

Page Company Representative Laura Mehrl （冯蓉媞） Company spokesperson, Director of Investor Relations Since May 2010 Experience: Director of Investor Relations, Diodes Incorporated, Plano, Texas Senior Business Development Manager, STMicroelectronics, Carrollton, Texas Sales Director for Analog Devices Inc., Shanghai, China Product Marketing Manager at Texas Instruments (TI), Dallas, Texas Senior Engineer at Lattice Semiconductor Inc., Hillsboro, Oregon Wafer fab design engineer and product engineer at TI, Lubbock, Texas Education: MBA with concentration in International Marketing, Texas Tech University BS in Electrical and Computer Engineering, University of Iowa

Page A leading global manufacturer and supplier of high-quality application specific, standard products within the broad discrete, logic, analog and mixed-signal markets, serving the Automotive, Industrial, Consumer, Communications, and Computing segments. About Diodes Incorporated

Company Overview NASDAQ: DIOD Founded in 1959 Headquartered in Plano, TX; 21 locations globally Manufacturing in UK, Germany, China, and Taiwan ISO9001:2008 Certified / TS16949:2009 Certified ISO14001 Certified Key acquisitions: Anachip Corporation, Taiwan Jan. 2006 Advanced Power Devices Nov. 2006 Zetex June 2008 Power Analog Microelectronics (PAM) Oct. 2012 BCD Semiconductor Mar. 2013 Pericom Semiconductor Nov. 2015 Over 7700 employees worldwide 27 consecutive years of profitability Page Global Operations and World-class Manufacturing & Packaging

Global Organization - TS16949 Manufacturing Page

Page 2018: Record Annual Revenue & Gross Profit Track Record of Consistent Growth ( In millions ) +41.2% +3.6% -0.2% -4.7% +10.8% +11.9% +30.5% +7.7% +15.2% *2018 estimate based on midpoint of 4Q’18 guidance as provided on November 6, 2018

Vision: Create Shareholder Value Page Goal 1: $1B Market Cap Goal 2: $1B Annual Revenue Goal 3: $1B Gross Profit Goal 4: $1B Profit Before Tax $1B Market Cap $1B Revenue $1B Gross Profit $1B PBT 2010 2017

Shifting Gears to Profitability Growth Page Mission: Profitability growth to expand shareholder value Strategy: Grow revenue to $2.5B at 40% GPM Goal: $1B Gross Profit by 2025

Business Model Page Implied 20172025 CAGR NR$1Bà 2.5B11.4% GP%35%à40% GP$ $360Mà $1B13.6% R&D%5%à 7% SG&A%15%à13% Op. Profit15%à20% Based on the midpoint of 4Q18 guidance, NR would grow 15.2% YoY, GP$ would grow 20% YoY in 2018

Targeted Market Segment Distribution Automotive Connected driving, comfort/style/safety, electrification/powertrain Industrial Embedded systems and precision controls Consumer IoT: wearables, home automation, smart infrastructure Communications Smart phones: advanced protocols and charging Computing Cloud computing: server, storage, data centers Page ~60% of revenue ~40% of revenue

Automotive: Applications Driving Growth Connected driving ADAS (Advanced Driver Assistance Systems) Telematics Infotainment Systems Comfort, style and safety Lighting Migration to LED and intelligent illumination Brushless Motor Control (BLDC) Migrating from Brushed to Brushless DC Motors Electrification/Powertrain Conventional Powertrain à Hybrid à Electrification Battery management Move to 48V battery Page

Automotive Brushless DC (BLDC) Motors Migrating from Brushed to BLDC Motors (~ 30 per vehicle) Automotive market moving to BLDC motors for reliability and efficiency Forecast to grow to 3.8 Billion units by 2021 Diodes Key Products $ / Car MOSFETs $18.75 Diodes Rectifiers $2.60 Hall Sensors $0.50 Gate Drivers $1.50 Crystals/XO $2.00 Total $25.35 Headlamp Height Adj Door Closer Adjustable Pedal Electronic Gear Change Tilt Steering Column Electric Trunk Rear Wiper Electric Seat Door Mirror Sunroof Wiper Cooling Fan Electronic VVT Traction Stability Blower Electronic Power Steering Water-pump Fuel Pump Electronic Parking Brake Power Window Page

Connected Driving Higher speed data rates and increased number of channels Robust and reliable data transfer ADAS, Telematics and Infotainment systems are merging into Connected Driving Forecast to grow to 280 Million units by 2021 1-PCIe n-PCIe n-PCIe IPCAM IPCAM IPCAM IPCAM Q-PCIe Packet SW Q-Xtal SoC Ethernet Controller or USB WiFi Controller Q-Clock Gen Diodes Key Products $ / Car Connectivity: (PCIe SW + ReDrivers, Signal SW, USB charger) $8.50 Crystal/XO and Clocks $3.50 Automotive Analog IC $1.52 MOSFETs, BJT $6.62 Diodes and Rectifiers $3.60 Total $23.74 Page

Automotive Summary * SemiCast Automotive Report 2016 forecast Diodes Key Products $ / Car Analog $2.02 Power Management $5.99 MOS/BJT $35.02 Diodes and Rectifiers $12.69 Timing and Connectivity $15.03 Total $70.75 Diodes can address $70 of semiconductor content per vehicle With 95M vehicles built in 2017, Diodes addressable SAM is $6.7 Billion. Page

Successful Growth in Automotive Automotive revenue 27% CAGR 2013 to 2017 Automotive represented 9% of Diodes’ total revenue in 2018 Automotive will continue to be an increasingly significant market segment for Diodes Diodes’ Automotive Revenue Page

Industrial: Automation and Precision Controls Page Increasing IC content in embedded systems Switching and signal path for networked systems and automation Signal conditioning and timing for precision controls Motor controls, sensors and power management for smart meters

IoT – Machine to Machine (M2M) Growth Opportunities: Power Xtal and clock Packet switch M2M – Dominated by short range technology 73% of them are short range, mostly Wi-Fi 2017: connections @ 750 million 2023: connections @ 2600 million M2M – By product IoT and M2M Modems Routers POS Wireless beacons Others x1 PCIe x4 PCIe FL series 25MHz XTAL 100MHz HCSL Clk PCIe Packet Switch Wi-Fi Wi-Fi Wi-Fi Wi-Fi Application Processor PCIe Clock Gen AC-DC LOGIC& STDLIN LDO LDSW DC-DC Discrete Wi-Fi Router Diodes Key Products $ / Device Analog $0.20 Power Management $1.30 MOS/BJT $3.39 Diodes and Rectifiers $2.99 Timing and Connectivity $3.50 Total $11.38 M2M – By application Smart Infrastructure POS Manufacturing / Industrial POS Page

Consumer: IoT Driving Power & Connectivity Requirements Diodes Key Products $ / Box Analog >$0.20 Power Management >$1.30 MOS/BJT >$10.00 Diodes and Rectifiers >$5.00 Timing and Connectivity $3.50 Total $20.00 Enterprise Smart Infrastructure Wearables Consumer & Home Asset Tracking Security & Surveillance Retail Page

Sensor IoT Segment: Smart Home Smart Home – up to 477Mu Safety and Security Climate Control Consumer Electronics Lighting control 400 100 200 300 Host Controller X1 PCIe2 100MHz HCSL Clk SSD X1 PCIe2 (or SATA controller) 25MHz Xtal PCIe CG PI6C557-05 PCIe Packet SW PI7C9X2G304SL Wireless Controller Wireless Controller Smart Home Gateway Smart Lighting MHz Xtal kHz Xtal AC Power LED Driver AC-DC Light User Interface Smart Speaker MHz Xtal SoC Growth Opportunities Power LED driver Xtal and clock Packet switch SoC MHz Xtal MOSFET TVS NAND SDRAM Wi-Fi LED Drive Audio Amp Digital Assistant Diodes Key Products $ / Box Analog $0.25 ~ $0.40 Power Management $1.80 MOS/BJT $1.10 Diodes and Rectifiers $0.50 Timing and Connectivity $3.50 Total $7.30 AC-DC Audio CODEC Wi-Fi Memory Ethernet port 2015 2016 2017 2018 2019 2020 World market for connected home devices (excluding energy and controls) Unit Shipments, 2015 - 2020 Safety & Security Climate Control Consumer Electronics Lighting & Controls AC Power SoC Page

Efficiency, Functionality and Control for Smartphones Focus on signal integrity and higher data rates Proliferation of USB Type-CTM connectivity and power delivery Power regulation and protection for new features Advanced power solutions for quick charge protocols Page

Smartphone Smartphone – Flat year in 2017 What’s next? Understand the impact Smart speaker/IoT rising AR / VR Foldable screens 5G Smartwatches Growth Opportunities Type-C MUX MOSFET LDO, OVP LDSW, Audio, DCDC, LED/OLED Driver, ACDC Diodes Key Products $ / Phone Analog $0.55 Power Management $1.50 MOS/BJT $0.33 Diodes and Rectifiers $0.42 Timing and Connectivity $3.00 Total $5.80 Company 2016 Shipment Volumes 2016 Market Share 2017 Shipment Volumes 2017 Market Share Year-Over-Year Change 1. Samsung 23.3 23.0% 29.3 29.1% 25.8% 2. OPPO 13.3 13.2% 17.2 17.0% 29.3% 3. Vivo 3.3 3.2% 7.2 7.2% 118.2% 4. Huawei 5.2 5.1% 5.4 5.4% 3.8% 5. Apple 4.6 4.5% 4.5 4.4% -2.2% Others 51.6 51.0% 37.1 36.8% -29.1% Total 101.3 100.0% 100.7 100.0% -0.6% Top Five Smartphone Companies in SEA, Calendar Year 2017 Source IDC Worldwide Quarterly Mobile Phone Tracker, March 2018 Page

Networking Segment WW enterprise and service provider router market grew 4% in 2017 to $12.5B Continues to exhibit healthy growth, driven by network refreshes and investments in the fast-growing campus and datacenter segments Diodes Key Products $ / Router Analog $0.20 Power Management $0.30 MOS/BJT $3.70 Diodes and Rectifiers $2.10 Timing and Connectivity $13.00 Total $19.30 Cisco Cisco Cisco Others Others Others Switching & Router Market Leaders Ethernet Switching Enterprise Routers Service Provider Routers Huawei, HPE, Arista, others Huawei, Technicolor, Juniper, others Nokia, Huawei, Juniper, others 0% 10% 20% 30% 40% 50% 60% Worldwide Market Share – Revenue. Source Synergy Research Group Growth Opportunities Power Xtal XO, and clock Packet switch ReDriver Page

Cloud Computing Accelerating Enterprise Market Page ReDriver support for USB connectivity Wide range of signal protocols: PCIe, SAS, SATA, GbE, USB MUX products for high capacity solid state storage Crystal oscillators for increasing clocking speeds

Computing Platform: Server/Storage Solution PCIe 40-128 lanes Pcie SSD Power Management Processor I2C L/S Server Platform ReDriver MEZZ Card PCIe ReDriver PCIE CLK Buffer HCSL Clock Occulink XO To Back-plane 4 x 10GE 1 x 1GE Middle-plane HDD Plane Reset IC System Clock Diodes Opportunity BMC LAN Card Storm Lake Module * Optional XO 100G QSFP SATA3 Note. Target on Workstation To Back-plane I2C Buffer Front Rear PCIe Slot XO M.2 IO Expander PCIe Clock Buffer GTL2014 PCIe NVMe VGA Switch 10G Re-driver TVS Combo Re-Driver SAS Switch SAS / SATA ReDriver USB3 Re-Driver USB2 Mux & Sleep Mode Charger TVS TVS PCIe Re-Driver USB2.0 USB3.0 BMC USB Type-C USB3 Re-Driver TVS PCIe Devices PCIe slot XTAL 32kH 25MHz 48MHz TVS TVS TVS TVS TVS Single End Buffer Expander Card SAS3, PCIe ReDriver RAID Card PCIe ReDriver XO PCIe Clock Buffer I2C Mux Bus Switch PCIe MUX MOSFETS BJT Diodes SBR Lewisburg Chipset Source: IDC, Diodes Marketing Server Platform Solution Total unit shipment Growth (CAGR) = 3.82% Almost all of Server vendors are our existing customers ODM direct has the highest volume – mainly in TW Diodes products are well positioned in this segment Connectivity, Signal Integrity, Timing, Standard Linear, Power Management, Power Switches and Protection devices WW Server total shipments (Mu) Diodes Key Products $ / Server Connectivity, Signal Integrity and Timing $7.00 Analog $0.50 Power Management $3.30 MOS/BJT $6.70 Diodes, Rectifiers and TVS $3.50 Total $21.00 DDR 4 Page HDD Packet Switch PCIe SSD

USB Type-C Total Solution: Smartphones Supports data, video, and power USB-C adoption to grow from 300M (2016) to 4B units (2021) - IHS Dec 2017 Vbus Tx/Rx Tx/Rx Tx/Rx Tx/Rx D+/D- SBU1, SBU2 D+, D- CC1, CC2 PMIC with PD Controller AUX+/AUX- Tx/Rx Tx/Rx Tx/Rx Tx/Rx TVS 10G Type-C USB /DP ALT ReDriver TVS TVS TVS I2C VR Switch TVS USB3.1G2 Application Processor USB3.1G2/DP1.4 AUX+/AUX- USB2.0 Tx/Rx USB3.1G2 Diodes Key Products $ / Device Connectivity, Signal Integrity and Timing $2.05 Analog (DCDC, LDO, Sleep Mode Charger etc) $0.64 Power Management Switch $0.46 TVS $0.50 Total $2.55 ~ $3.65 XTAL/ XO Power Switch Charger Detect USB Type-C Connector Page Data speed, flexibility, and simplicity of use are key drivers

USB Type-C Total Solution: Notebook, Tablet, PC and AIO Diodes Key Products $ / System Connectivity, Signal Integrity and Timing $3.25 Analog (DCDC, LDO, Sleep Mode Charger etc) $0.89 Power Management Switch $0.40 MOSFET/BJT $0.25 Diodes, Rectifiers and TVS $0.50 Total (per USB-C port) $5.29 Enables single interface to peripherals for data, video and charging Multiple USB-C ports per system D+,D- CC1 CC2 SBU1,SBU2 VBUS I2C USB Type-C Connector I2C PD Controller System Chipset Embedded Controller Adj. DCDC (5/9/15/20) Sleep Mode Battery Charger Power Switch (or Discrete FETs) Passive/Active Crossbar Mux/CC Controller/ ReDriver DP/USB Alt-Mode support USB2/Audio Switch DisplayPort D+,D- UART AUDIO Notebook, Tablet, PC & AIO TVS TVS TVS TVS TVS TVS TVS XTAL/XO Or Clock Page USB 3.1 Tx/Rx High level of integration and speed are key drivers

System Focus Industrial Controls Page

Complete Platform Solutions: Notebooks Page DCDC Converter CPU PCH MOSFET LED Driver USB 2.0 Switch A/V Codec DDR Regulator LDO Analog Switch TVS USB 3.0 ReDriver Crossbar Switch Vcore DCDC Controller Sleep / Charge Detect Video Switch MCU USB3 / DP Switch LSP Con LCD Panel TVS DP-to-VGA Converter Video Switch TVS HDMI ReDriver SATA / PCIe ReDriver HDD / SSD USB2 / 3 Switch USB Power Switch TVS Docking Sub-system DDR4 DIMM 3D Camera LDO USB3 ReDriver UART D+, D- Memory Bus DP0..3 Tx, Rx I2C D+, D- D+, D- AUXHPD+ AUXHPD- SATA / PCIe DDI USB3.0 eDP1.3 DP1.2b HDMI 1.4 TVS TVS LAN Switch MOSFET Audio Amplifier Sensor ACDC External Charger DCDC LDO Logic Sensor TVS USB Switch LED Driver Timing Signal Integrity Switching Connectivity Audio SBR ACDC Std Linear High-Speed Serial Connectivity SBR Diode Diode

Technology Focus Page Products 20Gbps ReDrivers and Switches Automotive Packet Switch for Telematics / ADAS Complete USB Type-CTM Signal Switching High speed clocking for cloud computing Ultra low power and low noise LDOs for IoT Low Cj TVS for signal integrity Lowest rDS(on) LDMOS for battery efficiency Compact QFN and DFN Power density PowerDI Chip scale packaging and plating capability Extensive multi-chip package technology High performance 8” MOSFET trench technology Advanced Epi bipolar transistor processes Proprietary rectifier technology Rugged automotive grade NMOS and PMOS Assembly/Test Wafer Fab

Key Differentiator – Packaging Design Page Focus: Miniaturization and Power Efficiency ~ 2018 PowerDI5060-8L PD3333-8L DFN0808-4 DFN0806-3 SOP-8/14/16L-EP MSOP-8/EP TO252-2/3/4/5L SOD123(F)/923 SOD523/323 TO220-5L TO262AA/AB QFN5050-32 DFN0604-3 2019 ~ ITO220AC-S DFN0806-6 DFN0603-2 TO220-2/3L PowerDI-5 PowerDI-5SP TSOT23-5/6 SOT25/26 SOT223/143 SOIC-14/16L SOP-8L DFN1114-3 (stack die) MSOP-8/10L QSOP-16/20L SOT523/353/363 ITO220S PDI-123/323 FC-DFN1212-4 TO263-2/3/5/7L SOT563/953/963 SWP-DFN1006-2 (Side-wall Plating) FC-SSOT-23 SWP-DFN2020E-6 (Side-wall Plating) DFN0606-3 DFN6040-22 TSSOP-8/14/16L(EP) FC -TSOT23-6L QFN2618A-16 (Chip on Lead） Power5060-8L K （2mil die） SWP-PDI5060-8L R TO252-4L C HS IntelliFET (3mil Al wire) QFN3035A-21 (MCM/Clip/Stack) PowerDI3333-8L ((2mil die) PD5060-8L S PowerDI3333-8 E (FC + Clip) PD3333D-8L （Stack Clip） SOIC-14L-EP (Smart HS Power Switch ) TO263-6L&7L (Stack die+ Al wire) PowerDI1012S (TOLL) SOIC-8L-EP Y (Monolithic HS IntelliFET) DFN1612B-8 (Epoxy printing) QFN2020B-12 FC-QFN2030-16 DFN3030N-8 （Pre-mold） PowerDI3025-20 QFN3535A-20 DFN1010H4C-4 PowerDI5060-8L T (GaN) PD8080(Ribbon) (Sep’19) PD5050 (FC + Clip) (Nov’19) CSP TSN3518 CSP PCSP0402 CSP DDFN0603 CSP TSN2718 CSP DDFN0402 CSP X3-DSN1006

Page Advanced Packaging Multi-Chip Packaging Miniaturization DDFN0402 the smallest discrete semiconductor package Dual-Flat No-Lead (DFN) DDFN (Encapsulated CSP) Chip-Scale Package (CSP) HS IntelliFET: ZXMS3001 Miniaturization and Multi-Chip Packaging

Page Shanghai-based packaging with capacity over 34 billion units Chengdu facility has potential capacity 3X of Shanghai Additional facilities in Neuhaus, Germany and Chengdu, China Two fabs in Shanghai (6” and 8”), one discrete fab in Oldham, UK (6”) Bipolar, BiCMOS, CMOS and BCD process Strong engineering capabilities Packaging Wafer Fabs Efficient Manufacturing + Superior Processes Economies of Scale: Capacity & Loading Percentage in SAT & CAT *CapEx Model = 5% - 9% of Revenue

Third Quarter 2018 Financial Performance Page In millions, except per share 3Q17 2Q18 3Q18 YoY Revenue $285.2 $304.1 $320.9 12.5% Gross Profit (GAAP) $96.3 $107.3 $115.2 19.6% Gross Profit Margin % (GAAP) 33.8% 35.3% 35.9% +210bp Net Income (GAAP) $14.5 $25.1 $30.9 Net Income (non-GAAP) $22.6 $29.3 $34.5 52.7% EPS (non-GAAP) $0.45 $0.58 $0.68 51% Cash Flow from Operations $40.9 $34.4 $35.5 EBITDA (non-GAAP) $46.8 $64.5 $72.0 53.9%

Balance Sheet Page Dec 31, 2017 Cash $248 $204 $150 Short-term Investments $30 $5 $7 Inventory $193 $217 $219 Current Assets $733 $662 $647 Total Assets $1529 $1489 $1467 Long-term Debt ( including the current portion) $413 $247 $166 Total Liabilities $708 $615 $515 Total Equity $820 $874 $952 Sept 30, 2018 In millions Dec 31, 2016

Revenue Profile as of 3Q 2018 By End Market Page 16% 27% 25% 23% 9% Industrial Communications Consumer Automotive Computing By Channel By Region 13% 76% 11% Asia Pacific North America 71% 29% Distribution OEM / EMS Europe

Page Revenue to be approximately $315 million, plus or minus 3 percent, or down 1.9% q/q GAAP gross margin to be 36.0%, plus or minus 1% Non-GAAP operating expenses, which are GAAP operating expenses adjusted for amortization of acquisition-related intangible assets, are expected to be approximately 21.0% of revenue, +/- 1% Interest expense to be approximately $2.0 million, and income tax rate is expected to be 29.5%, +/- 3% Shares used to calculate diluted EPS approximately 52.2 million Purchase accounting adjustments of $3.5 million, after tax, for Pericom and previous acquisition are not included in these non-GAAP estimates Fourth Quarter 2018 Business Outlook *Guidance as provided on November 6, 2018

Summary Vision: Expand shareholder value Mission: Profitability growth to drive 20% operating profit Next Strategic Goal: $1B gross profit Tactics: Increased focus on high-margin Automotive, Industrial and Pericom products Investment for technology leadership in target products, fab processes, and advanced packaging System solutions to drive business expansion Page