Schematic Review and Corrections

4:40

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Calculating gate charge power.

Calculating energy dissipation.

Analyzing discharge energy.

Querying datasheet for Qg.

Calculating power dissipation for MIC4127.

Using Knowledge Base Tool.

Searching web for: "DMT3020LDV-7 datasheet total gate charge Qg Ciss MIC4127YME datasheet peak output current supply voltage range"

Found 1 results.

Searching web for: "DMT3020LDV-7 datasheet pdf Diodes Incorporated Qg 7nC MIC4127 datasheet pdf peak output current 1.5A supply 4.5V to 20V"

Found 1 results.

Using Calculator Tool.

Using Calculator Tool.

Using Calculator Tool.

Using Calculator Tool.

Using Calculator Tool.

Using Calculator Tool.

Using Calculator Tool.

Using Calculator Tool.

Using Calculator Tool.

Using Calculator Tool.

Gathering data for calculations.

Short answer: No issues. With 12 V drive, 10 Ω series + 100 kΩ pulldown gives nanosecond-scale edges and milliwatt-level dissipation, well within 0603 ratings and within the driver’s capability.
Data from datasheets
  • MIC4127YME: dual driver, supply 4.5–20 V, peak source/sink 1.5 A (Microchip datasheet).
  • Q1/Q2 DMT3020LDV-7: total gate charge Qg typ = 7.0 nC at VGS = 10 V (Diodes Inc. datasheet).
Computed results (per FET, fPWM = 20 kHz, Vdrive = 12 V, Rg = 10 Ω)
  • Effective gate capacitance (from Qg): Ceff = Qg/V ≈ 0.7 nF.
  • Time constant: τ = Rg·Ceff ≈ 7 ns; rise-time 95% ≈ 3τ ≈ 21 ns; 99% ≈ 5τ ≈ 35 ns. This is about 0.07% of a 20 kHz period (50 µs), so switching speed is more than adequate.
  • Series resistor power (average): P_R ≈ Qg·V·f = 1.68 mW. Versus 0603 0.1 W rating, margin is huge.
  • Series resistor peak current at t=0: I_PEAK ≈ V/Rg = 1.2 A, within MIC4127YME’s 1.5 A peak rating.
  • Pulldown (100 kΩ) DC dissipation when gate is high: P_MAX = V²/R = 1.44 mW (at 100% duty). At 50% duty ≈ 0.72 mW. Also far below 0.1 W.
Actionable notes
  • Keep the 10 Ω series parts close to the MOSFET gates to damp ringing and reduce EMI.
  • The pulldown should reference the MOSFET source node (if the source is not hard-GND in all states) to avoid any chance of excessive negative VGS during transients.
  • With your 12 V drive and these values, no rise-time or power concerns are expected at 20 kHz.
43 days
@calculator 按40kHz PWM再算一次每路栅极电阻平均功耗和驱动损耗。
43 days

2:51

Chat History
Project
Calculator
Datasheet

Calculating gate resistor power.

Evaluating energy dissipation.

Analyzing energy dissipation.

Calculating power dissipation.

Preparing calculations for power dissipation.

Using Knowledge Base Tool.

Using Calculator Tool.

Using Calculator Tool.

Calculating power dissipation estimates.

计算基于 Qg = 7 nC(在 10 V 规格处取典型值)、Vdrive = 12 V、Rg = 10 Ω、fPWM = 40 kHz。结果为每路一只 MOSFET 的估算。
结果
  • 栅极驱动总损耗 Pgate ≈ Qg · Vdrive · f = 3.36 mW
  • 栅极串联电阻平均功耗 PRg(上界,假设驱动器输出内阻远小于 10 Ω,能量主要在 Rg 上耗散)≈ 3.36 mW
  • 驱动器内部动态损耗 Pdriver ≈ Pgate · Rdriver / (Rg + Rdriver)
    • 需数据手册给出 Rdriver(高、低端导通电阻)。若 Rdriver 远小于 10 Ω,则 Pdriver 仅占小部分;如需精算我可以拉取数据表参数代入。
  • 100 kΩ 下拉电阻功耗(与频率无关,取占空 D): Ppd = D · Vdrive² / 100 kΩ
    • D = 100% 时 Ppd = 1.44 mW;D = 50% 时 Ppd = 0.72 mW
说明
  • 上述 3.36 mW 同时也是“每周期门极充放电能量 Q·V 的平均功率”在 40 kHz 下的值;作为 PRg 的上界是合理、保守的布局热设计依据。
  • 若需要把 PRg 与 Pdriver 分摊到更精确的数值,请确认 MIC4127YME 输出级的典型导通电阻(高、低侧),我可以据此给出精确分摊并核对峰值电流与热负载余量。
补充缺失参数
分摊驱动器内阻
核对峰值门极电流
计算下拉电阻损耗
选电阻封装功率
43 days


XL1509-ADJE1
U1
100nF
Capacitance
100p F
47uH
Inductance
Inductance
+V
9V
1K
Resistance
500 Ω
6.8K
Resistance
500 Ω
3V3
10nF
Capacitance
100p F
SS34


  • Ground
    A common return path for electric current. Commonly known as ground.
  • Net Portal
    Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
  • Power Net Portal
    Wirelessly connects power nets on schematic. Identical to the net portal, but with a power symbol. Used to organize schematics and separate functional blocks. To wirelessly connect power net portals, give them the same designator. #portal #power
  • Generic Resistor
    A generic fixed resistor for rapid developing circuit topology. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0Ω 10Ω 100Ω 1.0kΩ 10kΩ 100kΩ 1.0MΩ 1.1Ω 11Ω 110Ω 1.1kΩ 11kΩ 110kΩ 1.1MΩ 1.2Ω 12Ω 120Ω 1.2kΩ 12kΩ 120kΩ 1.2MΩ 1.3Ω 13Ω 130Ω 1.3kΩ 13kΩ 130kΩ 1.3MΩ 1.5Ω 15Ω 150Ω 1.5kΩ 15kΩ 150kΩ 1.5MΩ 1.6Ω 16Ω 160Ω 1.6kΩ 16kΩ 160kΩ 1.6MΩ 1.8Ω 18Ω 180Ω 1.8KΩ 18kΩ 180kΩ 1.8MΩ 2.0Ω 20Ω 200Ω 2.0kΩ 20kΩ 200kΩ 2.0MΩ 2.2Ω 22Ω 220Ω 2.2kΩ 22kΩ 220kΩ 2.2MΩ 2.4Ω 24Ω 240Ω 2.4kΩ 24kΩ 240kΩ 2.4MΩ 2.7Ω 27Ω 270Ω 2.7kΩ 27kΩ 270kΩ 2.7MΩ 3.0Ω 30Ω 300Ω 3.0KΩ 30KΩ 300KΩ 3.0MΩ 3.3Ω 33Ω 330Ω 3.3kΩ 33kΩ 330kΩ 3.3MΩ 3.6Ω 36Ω 360Ω 3.6kΩ 36kΩ 360kΩ 3.6MΩ 3.9Ω 39Ω 390Ω 3.9kΩ 39kΩ 390kΩ 3.9MΩ 4.3Ω 43Ω 430Ω 4.3kΩ 43KΩ 430KΩ 4.3MΩ 4.7Ω 47Ω 470Ω 4.7kΩ 47kΩ 470kΩ 4.7MΩ 5.1Ω 51Ω 510Ω 5.1kΩ 51kΩ 510kΩ 5.1MΩ 5.6Ω 56Ω 560Ω 5.6kΩ 56kΩ 560kΩ 5.6MΩ 6.2Ω 62Ω 620Ω 6.2kΩ 62KΩ 620KΩ 6.2MΩ 6.8Ω 68Ω 680Ω 6.8kΩ 68kΩ 680kΩ 6.8MΩ 7.5Ω 75Ω 750Ω 7.5kΩ 75kΩ 750kΩ 7.5MΩ 8.2Ω 82Ω 820Ω 8.2kΩ 82kΩ 820kΩ 8.2MΩ 9.1Ω 91Ω 910Ω 9.1kΩ 91kΩ 910kΩ 9.1MΩ #generics #CommonPartsLibrary
  • Generic Capacitor
    A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF 10pF 100pF 1000pF 0.01uF 0.1uF 1.0uF 10uF 100uF 1000uF 10,000uF 1.1pF 11pF 110pF 1100pF 1.2pF 12pF 120pF 1200pF 1.3pF 13pF 130pF 1300pF 1.5pF 15pF 150pF 1500pF 0.015uF 0.15uF 1.5uF 15uF 150uF 1500uF 1.6pF 16pF 160pF 1600pF 1.8pF 18pF 180pF 1800pF 2.0pF 20pF 200pF 2000pF 2.2pF 22pF 20pF 2200pF 0.022uF 0.22uF 2.2uF 22uF 220uF 2200uF 2.4pF 24pF 240pF 2400pF 2.7pF 27pF 270pF 2700pF 3.0pF 30pF 300pF 3000pF 3.3pF 33pF 330pF 3300pF 0.033uF 0.33uF 3.3uF 33uF 330uF 3300uF 3.6pF 36pF 360pF 3600pF 3.9pF 39pF 390pF 3900pF 4.3pF 43pF 430pF 4300pF 4.7pF 47pF 470pF 4700pF 0.047uF 0.47uF 4.7uF 47uF 470uF 4700uF 5.1pF 51pF 510pF 5100pF 5.6pF 56pF 560pF 5600pF 6.2pF 62pF 620pF 6200pF 6.8pF 68pF 680pF 6800pF 0.068uF 0.68uF 6.8uF 68uF 680uF 6800uF 7.5pF 75pF 750pF 7500pF 8.2pF 82pF 820pF 8200pF 9.1pF 91pF 910pF 9100pF #generics #CommonPartsLibrary
  • Generic Inductor
    A generic fixed inductor for rapid developing circuit topology. *You can now change the footprint and 3D model at the top level anytime you want. This is the power of #generics
  • Terminal
    Terminal
    An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
  • RMCF0805JT47K0
    47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film #forLedBlink
  • 875105359001
    10uF Capacitor Aluminum Polymer 20% 16V SMD 5x5.3mm #forLedBlink #commonpartslibrary #capacitor #aluminumpolymer #radialcan
  • CTL1206FYW1T
    Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric) #forLedBlink
Volumetric: Wifi LED Strip controller thumbnail
Wi-Fi LED strip controller made with few goals:
Dual voltage support 12V and 24V 2 independent channels for color temperature adjustments No high pitch noise in all modes Powerful enough to handle current up to 17.5A (in total, limited by connectors) Control buttons on the device body Connectors for external buttons Can be used with already installed LED strips Support of open source firmware, like https://esphome.io/

Properties

Properties describe core aspects of the project.

Pricing & Availability

Distributor

Qty 1

Digi-Key

$0.37–$1.08

LCSC

$0.38

Mouser

$1.08

Assets

Wifi LED Strip Controller

Wifi LED Strip Controller

Wifi LED Strip ControllerThumbnail

Controls