FZT849TA - 30V 7A NPN BJT, 100MHz, SOT-223 | Diodes Incorporated
料号： FZT849TA ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $0.78 | $0.78 |
| 10 | $0.69 | $6.90 |
| 100 | $0.55 | $55.00 |
| 500 | $0.46 | $230.00 |
| 1,000 | $0.39 | $390.00 |
| 3,000 | $0.34 | $1,020.00 |
FZT849TA 概述
A bipolar junction transistor (BJT) is a three-terminal semiconductor device formed by sandwiching either P-type or N-type material between two layers of the opposite polarity, creating either NPN or PNP polarity. BJTs use a small base current to control a much larger collector current, acting as a current amplifier or a saturated switch. The FZT849TA belongs to the NPN variant and is engineered for medium-power switching and linear applications where a saturated high-side or low-side switch must deliver several amps with low conduction loss.
Key features include a VCBO of 60V, VCER of 40V, low VCE(sat) of 250 mV typical at 6.5 A, complementary PNP partner FZT949, and a built-in collector-tab that simplifies PCB heatsinking. The device is lead-free, RoHS compliant, halogen-free, and qualified to AEC-Q101 for automotive power-management and lighting loads.
Architecturally, the FZT849TA uses a planar epitaxial base design with a high-current die capable of sustaining 20A pulsed for inductive-load switching. The SOT-223 footprint exposes the collector through the rear tab, reducing thermal resistance from junction to ambient (θJA) to roughly 76 °C/W on the datasheet's reference copper pad, allowing multi-watt dissipation without a discrete heatsink.
Typical applications include DC-DC converter pass elements, motor driver low-side switches, automotive relay replacement, solenoid drivers, LED current regulators, and battery-protection circuits. The combination of high ICM and low VCE(sat) makes it especially suited for portable and automotive load management where efficiency and thermal performance dominate the BOM.
When designing with this device, derate power dissipation against ambient temperature using the θJA figure from the datasheet. Drive the base with sufficient base current to force saturation—roughly IC/10—and include a base-emitter resistor to guarantee fast turn-off in PWM applications.
This page consolidates distributor stock, parametric comparisons, drop-in alternatives, and PCB thermal guidance not found in the bare manufacturer datasheet.
直接替换替代料： FZT849TA ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
FZT849
✅ 直接替换📋 参考替代料（不在目录中）
FZT949TA
✅ 直接替换📋 参考替代料（不在目录中）
ZXTN2007GTA
✅ 直接替换📋 参考替代料（不在目录中）
ZTX849
✅ 直接替换📋 参考替代料（不在目录中）
ZTX849STZ
✅ 直接替换📋 参考替代料（不在目录中）
FZT849TA 最大额定值与电气特性
| 晶体管类型 | NPN Bipolar (BJT) |
| 封装 | SOT-223-3 (4-pin, 3+tab) |
| 集电极-基极电压（Vcbo） | 60 V |
| 集电极-发射极电压（Vceo） | 30 V |
| Collector-Emitter Voltage (VCER) | 40 V |
| 发射极-基极电压（Vebo） | 7 V |
| Continuous Collector Current (IC) | 7 A |
| Peak Pulse Collector Current (ICM) | 20 A |
| Power Dissipation (PD) | 3 W |
| 过渡频率（ft） | 100 MHz |
| DC Current Gain (hFE) | 100 min at 1A / 10V |
| VCE(sat) Typical | 250 mV at IC = 6.5 A |
| Equivalent On-Resistance RCE(sat) | 36 mΩ at 5 A |
| 工作温度范围 | -55 °C to +150 °C |
| 安装类型 | Surface Mount |
| RoHS / Lead-Free | Yes / Yes |
| AEC-Q101 Qualification | Qualified |
| Complementary PNP | FZT949 |
FZT849TA 引脚配置
| 引脚 1 | Base — Base control terminal |
| 引脚 2 | Collector — Collector (electrically tied to tab) |
| 引脚 3 | Emitter — Emitter terminal |
| 引脚 4 | Collector (Tab) — Collector / thermal pad; solder to copper pour |
FZT849 安全工作区 (DC)
典型应用
FZT849TA 适用于 7 应用s: 12V Automotive Relay Replacement, DC-DC Converter Pass / Switch Element, Motor Driver Low-Side Switch, LED Current Regulator / Driver, Solenoid and Valve Driver, Battery Protection and Load Switching, Linear Voltage Regulator Pass Element.
12V Automotive Relay Replacement
The FZT849TA's 7 A continuous collector current, 36 mΩ RCE(sat) at 5 A, and AEC-Q101 qualification make it ideal for direct-replacement of electromechanical relays on automotive 12 V buses. With VCBO of 60 V and VCER of 40 V, the device tolerates 12 V load-dump transients up to ~35 V (clamped). Designers typically drive it with a Darlington buffer or a microcontroller PWM output driving ~50 mA base current, switching inductive loads like fuel pumps, HVAC blowers, and headlamp relays. The SOT-223 collector tab simplifies thermal management on chassis-grounded copper pours.
推荐
DC-DC Converter Pass / Switch Element
In buck and boost converters operating up to 30 V, the FZT849TA serves as the main switching transistor with its 100 MHz fT enabling high-frequency PWM operation. The 250 mV VCE(sat) at 6.5 A minimizes conduction loss, while the 20 A ICM rating provides ample margin for transient overload. Place it on the low-side with a freewheeling diode; the SOT-223 collector tab thermal pad ties to a 25 mm × 25 mm copper pour to sustain 2-3 W dissipation. Designers use this part in portable battery packs, USB-PD adapters, and point-of-load regulators for industrial control.
推荐
Motor Driver Low-Side Switch
The FZT849TA excels as a low-side switch for brushed DC motors in robotics, small appliances, and automotive actuators. Its 7 A continuous and 20 A peak pulse current accommodate motor inrush, while the 36 mΩ on-resistance keeps dissipation under 1 W for typical 3 A continuous motor loads. Drive the base at ~10% of IC (around 300-700 mA for 3-7 A motors) with a base-emitter resistor for fast turn-off. The SOT-223 footprint saves board space versus TO-220 alternatives, and the integrated collector tab provides thermal relief for sustained motor stall currents.
推荐
LED Current Regulator / Driver
For high-brightness LED arrays in automotive lighting, signage, and architectural illumination, the FZT849TA operates as a linear current regulator. Its 7 A capacity drives multiple high-power LEDs in series/parallel strings, and the low VCE(sat) reduces voltage overhead versus MOSFET alternatives in low-voltage 12-24 V systems. Configure it as a constant-current source by sensing emitter current through a small resistor and feeding back to a controller or discrete error amp. The AEC-Q101 qualification suits automotive headlamp and DRL modules where reliability is critical.
推荐
Solenoid and Valve Driver
Industrial solenoid valves, pneumatic actuators, and hydraulic control valves draw 1-5 A holding current with 5-10x inrush surges. The FZT849TA's 20 A peak pulse current handles inrush without current-limiting resistors, while the 7 A continuous rating covers holding current. Place a flyback diode across the solenoid to protect against the 60 V VCBO during inductive turn-off. The SOT-223 footprint allows dense multi-channel driver boards for process control and factory automation systems.
推荐
Battery Protection and Load Switching
In portable battery packs and UPS systems, the FZT849TA serves as a high-side or low-side load disconnect switch. Its 30 V VCEO rating covers 4-6 cell Li-ion packs (up to 25.2 V), and the 36 mΩ RCE(sat) minimizes voltage drop across the protection element. Use it with a controller that monitors battery voltage and disconnects load during over-discharge. The AEC-Q101 rating makes the part suitable for EV auxiliary battery management and e-bike pack protection circuits where reliability under thermal cycling matters.
推荐
Linear Voltage Regulator Pass Element
For post-regulation after a switching converter, or as a simple adjustable linear regulator, the FZT849TA acts as the series pass element. With VCBO = 60 V and PD = 3 W, it regulates loads up to 1 A continuously in TO-220-equivalent SOT-223 footprint. Use it as an emitter follower or in classic Zener-referenced linear regulator topologies for low-noise analog power rails. The low VCE(sat) gives better dropout performance than Darlington-based regulators, while the 100 MHz fT supports fast transient response in audio and instrumentation power supplies.
推荐
推荐产品汇总
工程参考数据： FZT849TA ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | FZT849 | FZT949TA | ZXTN2007GTA | ZTX849 |
|---|---|---|---|---|---|
| Brand | Diodes Incorporated | Diodes Incorporated | Diodes Incorporated | Diodes Incorporated | Diodes Incorporated (Zetex) |
| Package | SOT-223 | SOT-223 - same | SOT-223 - same | SOT-223 - same | SOT-223 - same |
| Polarity | NPN | NPN | PNP | NPN | NPN |
| VCEO | 30 V | 30 V | -30 V | 30 V | 30 V |
| Continuous Collector Current | 7 A | 7 A | -7 A | 7 A | 7 A |
| Peak Pulse Current | 20 A | 20 A | -20 A | 20 A | 20 A |
| AEC-Q101 Qualified | Yes | No (commercial grade) | Yes | Yes | No |
| Power Dissipation (PD) | 3 W | 3 W | 3 W | 3 W | 3 W |
关键差异点
- AEC-Q101 qualified with extremely low RCE(sat) （对比 ZTX849)
- Matched complementary PNP available on same footprint （对比 ZXTN2007GTA)
- 100 MHz transition frequency for high-speed switching （对比 FZT849 (commercial))
设计说明
Estimated: at IC = 3 A, VCE = 1 V, dissipation is 3 W, which would push junction temperature 228 °C above ambient on the standard 76 °C/W SOT-223 footprint—exceeding the 150 °C TJ,max rating. Either limit IC to ~1.7 A at TA = 25 °C or expand the copper pad to 50 mm × 50 mm with thermal vias to drop θJA to ~40 °C/W. Always check the datasheet Figure 6 (Power Derating) curve and apply at least a 20 % margin.
The SOT-223 collector tab is the only thermal path for multi-watt dissipation. Solder the tab to a copper pour of at least 25 mm × 25 mm (1 oz) for the rated 3 W; add thermal vias (0.3 mm diameter, 1 mm pitch) to inner ground planes for 2-3 W applications. Keep high-current traces wide (≥1 mm per ampere) to avoid secondary heating that feeds back into the junction. Place the base-drive resistor within 5 mm of the base pin to minimize parasitic inductance.
Driving the base with too little current (IB < IC/10) leaves the transistor in the active region and pushes VCE(sat) above 1 V, causing rapid thermal failure. Conversely, driving IB too high wastes power in the base resistor. Add a base-emitter resistor (1-10 kΩ) to guarantee turn-off in PWM operation; without it the base can remain charged after the drive signal goes low. For inductive loads, always include a flyback diode rated above the supply voltage plus 2 × L × dI/dt spike.
Keep the gate/base drive return path close to the emitter to avoid ground-bounce that can momentarily forward-bias the base-emitter junction and cause shoot-through. Route high-current traces (collector, emitter) directly to the load and to the copper pour, away from the base drive. For switching applications above 100 kHz, use a Kelvin connection to the emitter pin so the base drive sees only the bond-wire inductance, not the load-current return.
合规信息
AEC-Q101 qualified per FZT849 datasheet. Lead-free, halogen-free, and RoHS compliant per Diodes Incorporated product page. MSL Level 1 per PartGenie database.
