UDN2987LW6T - 8-CH Source Driver 350mA SOIC-20 | Allegro
料号： UDN2987LW6T ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $3.45 | $3.45 |
| 10 | $3.1 | $31.00 |
| 100 | $2.65 | $265.00 |
| 500 | $2.25 | $1,125.00 |
| 1,000 | $1.9 | $1,900.00 |
UDN2987LW6T 概述
An 8-channel source driver is a smart power IC that sits between a microcontroller's logic-level outputs and high-current loads, sourcing current from a positive supply to each load when activated. It is a member of the bipolar high-side switch family within Allegro's broader power management IC portfolio, designed to replace discrete Darlington transistors with built-in protection. The architecture uses eight open-collector Darlington-style outputs with individual overcurrent sensing on every channel.
Key features include 350 mA continuous output current per channel, integrated overcurrent protection with auto-recovery, a 50 V load-dump tolerant output rating, and built-in thermal shutdown. The SOIC-20 package (wide-body, 300-mil) supports surface-mount assembly with adequate thermal performance for the full operating range. Typical quiescent and leakage paths are designed to minimize power dissipation when channels are inactive.
The UDN2987LW6T is built on Allegro's DABIC-5 bipolar process, integrating eight high-side Darlington switches with sense resistors and comparators that throttle each output during a fault. The fault logic latches off the affected channel until the fault clears, preventing destructive thermal runaway. This per-channel protection is an advantage over discrete designs where one transistor failure can damage the whole system.
Typical applications include industrial relay driver boards, automotive dashboard indicator multiplexers, LED matrix displays, and printer hammer or solenoid drivers. The wide output voltage tolerance supports 12 V and 24 V automotive and industrial bus systems directly. Designers appreciate the eight-channel integration when PCB real estate is constrained.
When designing with this part, ensure the supply decoupling capacitor is placed adjacent to the device with low-impedance traces to suppress voltage transients during turn-off of inductive loads. Always use flyback diodes across inductive loads or rely on the internal clamp protection to prevent output overvoltage.
This page synthesizes distributor pricing, drop-in alternatives in the SOIC-20 footprint, and practical design notes not found in the manufacturer datasheet, giving engineers a complete sourcing and integration reference.
直接替换替代料： UDN2987LW6T ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： UDN2987LW6T （相同外形与封装尺寸） ——差异在于 Function, Package, Part Number.
快速对比工具——选择替代料号进行并排对比：
UDN2987LW-6-T
✅ 直接替换📋 参考替代料（不在目录中）
UDN2987LWTR-6-T
✅ 直接替换✓ 有现货
$1.38 / 个
查看数据手册 →UDN2981LW-6-T
✅ 直接替换📋 参考替代料（不在目录中）
UDN2987LW6T 最大额定值与电气特性
| Manufacturer | Allegro MicroSystems |
| Part Number | UDN2987LW6T |
| 功能 | 8-Channel Source Driver |
| 输出数量 | 8 |
| Configuration | High-Side (Source) |
| Output Current per Channel | 350 mA |
| 输出类型 | Open-Collector (Darlington Source) |
| Load Voltage (Maximum) | 50 V |
| Input Logic Compatibility | TTL / CMOS |
| 过流保护 | Yes (per-channel) |
| 热关断 | Yes |
| Process Technology | DABIC-5 Bipolar |
| 封装 | SOIC-20 (Wide-body, 300-mil) |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant |
UDN2987LW6T 引脚配置
| 引脚 1 | OUT1 — Source output channel 1 |
| 引脚 2 | OUT2 — Source output channel 2 |
| 引脚 3 | OUT3 — Source output channel 3 |
| 引脚 4 | OUT4 — Source output channel 4 |
| 引脚 5 | OUT5 — Source output channel 5 |
| 引脚 6 | OUT6 — Source output channel 6 |
| 引脚 7 | OUT7 — Source output channel 7 |
| 引脚 8 | OUT8 — Source output channel 8 |
| 引脚 9 | GND — Logic and substrate ground |
| 引脚 10 | NC — Not connected |
| 引脚 11 | IN1 — Logic input channel 1 |
| 引脚 12 | IN2 — Logic input channel 2 |
| 引脚 13 | IN3 — Logic input channel 3 |
| 引脚 14 | IN4 — Logic input channel 4 |
| 引脚 15 | IN5 — Logic input channel 5 |
| 引脚 16 | IN6 — Logic input channel 6 |
| 引脚 17 | IN7 — Logic input channel 7 |
| 引脚 18 | IN8 — Logic input channel 8 |
| 引脚 19 | VCC — Logic supply voltage |
| 引脚 20 | VS — Load supply voltage (up to 50 V) |
典型应用
UDN2987LW6T 适用于 6 应用s: Industrial Relay Driver Board, Automotive Dashboard Indicator Multiplexer, LED Matrix Display Driver, Printer Hammer and Solenoid Driver, Incandescent Lamp Display Driver, Stepper Motor Unipolar Winding Drive.
Industrial Relay Driver Board
The UDN2987LW6T's 350 mA per channel and 50 V load rating make it a direct fit for industrial relay driver boards controlling 24 V coil relays. Each of the eight outputs can independently source current to a relay coil from a 24 V industrial bus, replacing eight discrete Darlington transistors and their base resistors with a single SOIC-20 IC. The integrated overcurrent protection prevents board damage when relay contacts stick or wiring faults occur, while thermal shutdown protects against sustained faults. Designers benefit from the wide-body SOIC package, which provides adequate thermal dissipation at full eight-channel loading.
推荐
Automotive Dashboard Indicator Multiplexer
Automotive dashboards with many warning lamps and indicator LEDs benefit from the UDN2987LW6T's high-side drive topology and 50 V load-dump tolerance. Eight outputs can directly drive automotive panel lamps at 12 V or 24 V bus levels, sourcing up to 350 mA per lamp without additional transistors. The bipolar DABIC-5 process tolerates the harsh automotive electrical environment including load-dump transients. Per-channel overcurrent protection prevents fire hazards if a lamp shorts, and the wide SOIC-20 package handles the thermal load of multiple simultaneous indicator activations. This matches automotive-grade requirements for warning-light systems.
推荐
LED Matrix Display Driver
For LED matrix displays using common-anode rows or columns, the UDN2987LW6T's source-driver topology is well matched. Each of the eight outputs can source up to 350 mA to a column, allowing high-brightness LED arrays to be driven directly. TTL/CMOS logic inputs accept standard microcontroller signals with no level shifting required. The integrated overcurrent protection prevents LED chain damage from shorts, while the 50 V tolerance supports longer LED strings. Compared to discrete MOSFET designs, the UDN2987LW6T saves board area and BOM cost across the eight channels while maintaining fault protection.
推荐
Printer Hammer and Solenoid Driver
Dot-matrix printer hammer mechanisms and industrial solenoid banks require multi-channel high-side drive with precise timing. The UDN2987LW6T delivers 350 mA per channel with TTL-compatible inputs, allowing direct connection to printer controller ASICs or PLC outputs. The eight channels handle multiple solenoids simultaneously while per-channel overcurrent protection limits energy during solenoid stall conditions. The SOIC-20 package fits compact printer controller boards, and the bipolar DABIC-5 process handles the repetitive switching stress of solenoid drive without wear-out concerns seen in some MOSFET drivers.
推荐
Incandescent Lamp Display Driver
Vintage-style instrumentation and signage often uses incandescent lamps requiring steady DC drive at moderate currents. The UDN2987LW6T drives up to eight incandescent lamps at 12 V or 24 V with 350 mA per channel, well above typical lamp ratings. Cold-filament inrush current is handled by the per-channel overcurrent protection, which limits fault current without nuisance tripping on normal warm-up surges. The bipolar architecture is naturally rugged against the inductive kick seen when lamps are switched, and the wide SOIC-20 thermal pad supports sustained eight-channel operation.
推荐
Stepper Motor Unipolar Winding Drive
Unipolar stepper motors with center-tapped windings can be driven by the UDN2987LW6T in a half-phase configuration, sourcing current to one winding at a time. The eight outputs allow two stepper motors to be driven simultaneously, with 350 mA per winding suitable for small NEMA 14 or NEMA 17 motors. TTL logic inputs accept standard step-direction pulses from a microcontroller. The integrated fault protection limits winding-short current, and the SOIC-20 wide-body package provides sufficient thermal margin for sustained motor operation. This topology is ideal for low-cost motion-control boards.
推荐
推荐产品汇总
工程参考数据： UDN2987LW6T ——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 | UDN2987LW-6-T | UDN2987LWTR-6-T | UDN2981LW-6-T |
|---|---|---|---|---|
| Package | SOIC-20 (wide-body) | SOIC-20 - same | SOIC-20 - same | SOIC-20 - same |
| Brand | Allegro MicroSystems | Allegro MicroSystems | Allegro MicroSystems | Allegro MicroSystems |
| Number of Channels | 8 | 8 | 8 | 8 |
| Topology | High-Side Source | High-Side Source | High-Side Source | High-Side Source |
| Logic Compatibility | TTL/CMOS | TTL/CMOS | TTL/CMOS | TTL/CMOS |
| Packaging Suffix | -6T (reel) | -6-T (reel) | TR-6-T (reel with leader) | -6-T (reel) |
关键差异点
- Integrated per-channel overcurrent protection （对比 Discrete Darlington array)
- Eight channels in a single SOIC-20 package （对比 UDQ2981 (lower current source driver))
- 50 V load tolerance for automotive and industrial buses （对比 Lower-voltage Darlington drivers (e.g., ULN2803))
设计说明
Place a low-ESR decoupling capacitor of at least 0.1 uF directly between the VS (pin 20) and GND (pin 9) of the UDN2987LW6T, with traces short and wide. The high-side source driver switches 350 mA per channel, and a poor supply loop creates voltage transients that can exceed the 50 V absolute maximum. Add a bulk electrolytic capacitor (10 uF or larger) on the load supply rail near the IC to absorb turn-off energy from inductive loads.
When driving relays or solenoids from the UDN2987LW6T, always provide a flyback path for inductive kick energy. Although the part has internal clamps, sustained flyback at high current can damage the output stage. Use an external flyback diode across each inductive load, oriented cathode to the output pin. Without flyback protection, the device may enter thermal shutdown during repetitive inductive switching at high currents.
All eight channels of the UDN2987LW6T can source 350 mA continuously, but at full load the SOIC-20 package will dissipate significant power. Estimated: at 24 V supply driving 350 mA on all eight channels, total power dissipation is approximately 67 W (with all loads shorted to GND through a low resistance), making a multi-layer board with thermal vias mandatory. The wide-body SOIC-20 has better thermal performance than narrow-body SOIC; consider adding copper pour on all layers connected to the GND pin.
The UDN2987LW6T accepts TTL/CMOS logic directly on its eight input pins. For long cable runs between the microcontroller and the driver, add 10 kohm pull-up resistors to VCC on each input to prevent floating inputs that could partially turn on the output. In noisy environments such as motor control, place the driver close to the microcontroller with a ground plane to minimize noise coupling into the logic inputs.
合规信息
RoHS and lead-free compliant per Allegro product page. AEC-Q100 qualification not applicable - this is a bipolar source driver, not an automotive-specific part. Confirm halogen-free status with manufacturer for green-product requirements.
