UCC21521 - 4A/6A 5.7kVrms Isolated Gate Driver | TI
MPN： UCC21521DWR ✓ 啟用中UCC21521DWR 概覽
An isolated gate driver is a power management IC that translates low-voltage control logic into the high gate-drive current required to switch power transistors while maintaining galvanic isolation between controller and power stage. Within the power electronics hierarchy it sits between PWM controllers (DSPs, microcontrollers) and the power semiconductors they control, and is essential for safety and noise immunity in high-voltage converters.
Key features include 19-ns typical propagation delay, 10-ns minimum pulse width, 5-ns maximum delay matching, and 6-ns maximum pulse-width distortion. These timing parameters enable precise, synchronized switching that reduces switching losses and EMI. Programmable dead time prevents shoot-through in half-bridge configurations, and the DIS enable pin supports power sequencing and fault protection.
The UCC21521 uses TI capacitive isolation technology delivering CMTI of at least 100 V/ns for reliable operation in high-dv/dt environments such as SiC-based converters. Input pins use TTL and CMOS-compatible thresholds, allowing direct interface with 3.3-V microcontrollers and DSPs. The universal architecture supports dual low-side, dual high-side, or half-bridge driver configurations, and the device operates from -40C to +125C.
Typical applications include motor drives, solar inverters, EV onboard chargers, and isolated DC-DC converters, where the 4-A/6-A drive strength and 5-MHz capability suit SiC MOSFET and IGBT power stages.
Design tip: place decoupling capacitors close to VCCI and VDDA/VDDB pins and minimize gate-loop parasitic inductance to achieve specified timing performance and avoid dv/dt-induced false triggering.
直接替換替代品，適用於 UCC21521DWR — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： UCC21521DWR （相同外形與佔位） — 差異在於 Package, Isolation Rating, Isolation Technology, Automotive Qualification, Input Threshold.
UCC21521Q-Q1
✅ 直接替換聯絡詢價
查看資料表 →UCC21520Q-Q1
✅ 直接替換聯絡詢價
查看資料表 →UCC21540QDWKRQ1
✅ 直接替換✗ 缺貨
$2.21 / 單位
查看資料表 →UCC21550Q-Q1
✅ 直接替換聯絡詢價
查看資料表 →UCC21530Q-Q1
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →NCP51520
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
UCC21521DWR 最大額定值與電氣特性
| Channel Count | 2 |
| Peak Source Current | 4 A |
| Peak Sink Current | 6 A |
| Isolation Rating | 5700 Vrms |
| CMTI | 100 V/ns (minimum) |
| Propagation Delay | 19 ns (typical) |
| Delay Matching | 5 ns (maximum) |
| Pulse-Width Distortion | 6 ns (maximum) |
| Minimum Pulse Width | 10 ns |
| Max Switching Frequency | 5 MHz |
| Isolation Technology | Capacitive coupling |
| Input Threshold | TTL and CMOS compatible (3.3 V logic) |
| Enable / Disable Pin | Yes (DIS) |
| 工作溫度 | -40C to +125C |
| 封裝 | SOIC-16 (DW) |
| 安裝類型 | Surface Mount |
| Configurations | Dual low-side, dual high-side, or half-bridge |
| RoHS 狀態 | Compliant |
UCC21521DWR 腳位配置
| 腳位 1 | VCCI — Input-side supply voltage |
| 腳位 2 | GND — Input-side ground |
| 腳位 3 | INA — Input A, TTL/CMOS compatible |
| 腳位 4 | NC — No connect |
| 腳位 5 | DIS — Disable input (enable control) |
| 腳位 6 | NC — No connect |
| 腳位 7 | NC — No connect |
| 腳位 8 | INB — Input B, TTL/CMOS compatible |
| 腳位 9 | NC — No connect |
| 腳位 10 | GNDB — Output B ground reference |
| 腳位 11 | OUTB — Gate drive output B (6-A sink) |
| 腳位 12 | VDDB — Output B supply |
| 腳位 13 | VDDB — Output B supply |
| 腳位 14 | VDDB — Output B supply |
| 腳位 15 | OUTA — Gate drive output A (6-A sink) |
| 腳位 16 | VDDA — Output A supply |
典型應用
UCC21521DWR 適用於 6 應用s: Industrial Motor Drives, Solar Inverters, EV Onboard Chargers, Isolated DC-DC Converters, SiC MOSFET Half-Bridge Power Stages, Battery Management and Test Equipment.
Industrial Motor Drives
In three-phase inverters for industrial motor drives, the UCC21521 drives the low-side and high-side IGBT or SiC MOSFET gates of each phase leg with 4-A source and 6-A sink currents, enabling switching frequencies well into the tens of kilohertz. Its 19-ns propagation delay and 5-ns delay matching keep PWM channels synchronized, reducing torque ripple and dead-time losses. The 5.7-kVrms reinforced barrier with 100-V/ns CMTI withstands dv/dt transients at the switch node, while the DIS pin supports safe fault shutdown of all gates simultaneously.
推薦
Solar Inverters
Grid-tied solar inverters combine an MPPT DC-DC boost stage with a DC-AC H-bridge, both requiring isolated gate drive from a grounded controller. The UCC21521's 5.7-kVrms reinforced isolation provides the galvanic barrier between the DSP PWM outputs and the floating power-switch gates, while 100-V/ns CMTI keeps the outputs stable against boost-stage dv/dt. Its universal architecture supports dual low-side boost configurations and half-bridge arrangements, and the 4-A/6-A drive quickly charges large gate capacitances to minimize switching loss and maximize conversion efficiency.
推薦
EV Onboard Chargers
EV onboard chargers use isolated LLC or phase-shifted full-bridge converters where the UCC21521 provides the isolated gate-drive barrier for the primary-side power switches. Its 5.7-kVrms rating satisfies reinforced-isolation requirements between the high-voltage battery bus and low-voltage control electronics, and the 100-V/ns CMTI handles hard-switching transients. With a -40C to +125C operating range and the automotive-qualified UCC21521Q-Q1 variant available, the driver meets underhood and harsh-environment requirements while the DIS pin enables coordinated shutdown during fault conditions.
推薦
Isolated DC-DC Converters
In high-density isolated DC-DC converters such as full-bridge and push-pull topologies, the UCC21521 drives both primary-side switches with tight 5-ns channel matching, which maintains flux balance in the transformer and prevents saturation. The 4-A/6-A drive strength supports fast edge rates up to 5 MHz, allowing small magnetics and high power density. Capacitive coupling delivers the isolation barrier without optocoupler aging effects, ensuring consistent 19-ns delay over lifetime, while TTL/CMOS-compatible inputs interface directly with 3.3-V digital controllers.
推薦
SiC MOSFET Half-Bridge Power Stages
SiC MOSFETs switch with very high dv/dt, and the UCC21521 is explicitly designed for this environment: its minimum 100-V/ns CMTI prevents dv/dt-induced false turn-on, and the 6-A sink current rapidly discharges gate charge to hold the SiC switch firmly off during opposite-switch transients. Programmable dead time via the interlock logic prevents shoot-through in half-bridge legs, and 19-ns delay plus 6-ns maximum pulse-width distortion keeps high-frequency (hundreds of kHz to MHz) PWM accurate, maximizing the efficiency benefits of SiC technology.
推薦
Battery Management and Test Equipment
High-voltage battery testers and BMS-adjacent power conversion stages need safe isolated drive of load switches and converter transistors. The UCC21521's 5.7-kVrms isolation protects low-voltage measurement circuitry from the battery bus, while the DIS enable pin allows the test controller to gate off power stages immediately on fault detection. The -40C to +125C range and capacitive-isolation robustness ensure stable timing (19-ns delay, 6-ns PWD) across environmental stress, supporting repeatable, high-accuracy battery cycling and formation equipment.
推薦
推薦產品摘要
工程參考資料，適用於 UCC21521DWR — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | UCC21521Q-Q1 | UCC21520Q-Q1 | NCP51520 |
|---|---|---|---|---|
| Package | SOIC-16 (DW) | SOIC-16 (DW) - same | SOIC-16 (DW) - same | SOIC-16 - similar, verify footprint |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | onsemi |
| AEC-Q100 Qualification | No (standard grade) | Yes (Q1) | Yes (Q1) | No |
主要差異化特點
- DIS enable pin for sequencing and fault shutdown (對比UCC21520Q-Q1)
- Reinforced 5.7-kVrms barrier with >=100-V/ns CMTI (對比NCP51520)
- Universal architecture (dual low-side, dual high-side, half-bridge) (對比UCC21540QDWKRQ1)
設計說明
Place 100-nF to 1-uF decoupling capacitors within 2 mm of VCCI/GND and VDDA/VDDB to their respective grounds. Keep the gate loop (VDD-OUT-gate-source return) as short and small as possible; excessive parasitic inductance causes gate ringing, overshoot, and dv/dt-induced turn-on. Per the TI datasheet typical application, add an external gate resistor to control switching speed and damp ringing.
Unused input pins must not float: tie INA and INB to GND when a channel is not driven, and pull DIS to the inactive level. Floating inputs near thresholds can cause output chatter under high-dv/dt. Use short, ground-referenced traces from the controller to INA/INB, and add a small RC filter if the PWM source is noisy or routed near switching nodes.
When substituting UCC21520 or competitor parts, verify pin 5 (DIS) logic first - TI E2E forum threads document failures from reversed enable logic between UCC21521 and UCC21541. Also confirm VCCI range compatibility with your controller supply (3.3-V vs 5-V logic) and ensure output supply rails (VDDA/VDDB) respect the datasheet absolute maximum limits for your gate voltage.
Size the VDDA/VDDB supply for the total gate charge: I_avg = Qg x fsw per channel. For example, a 60-nC SiC MOSFET at 500 kHz needs 30 mA average per channel plus margin for the driver quiescent current. Under-supplied rails cause slower switching and reduced 4-A/6-A peak capability, increasing switching losses.
合規資訊
RoHS compliant per TI product page. AEC-Q100 qualification applies to the UCC21521Q-Q1 variant, not the standard part. Additional compliance details not present in provided data.
