UDN2982LW-T - 8-CH 500mA 80V Source Driver | Allegro | 20-SOIC
Référence : UDN2982LW-T ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $6.55 | $6,55 |
| 10 | $5.84 | $58,40 |
| 100 | $4.96 | $496,00 |
| 500 | $4.21 | $2 105,00 |
| 1 000 | $3.78 | $3 780,00 |
UDN2982LW-T Présentation
A source driver is an integrated power switch that pulls current from the load to the positive supply rail when activated by a logic-level input, complementing the more common sink driver that pulls the load to ground. Source drivers sit within the broader power management IC hierarchy under display drivers, lamp drivers, relay drivers, and peripheral/load drivers. Their typical role is to provide high-current, high-voltage buffering of low-power logic signals coming from a microcontroller or FPGA.
Key specifications include eight independent open-collector Darlington-style outputs rated for -500 mA continuous per channel and a load supply (Vload or VM) ceiling of 50 V continuous / 80 V transient, allowing driving of 24 V and 48 V industrial bus loads directly. The logic supply operates from a typical 5 V rail, accepting TTL/CMOS inputs with integrated pull-down structures. Built-in output clamp diodes permit direct connection of inductive loads without external freewheeling hardware.
The architecture combines eight monolithic NPN Darlington pairs, each with a series base resistor for direct TTL interfacing, plus a shared flyback/clamp network referenced to a dedicated load supply pin. This topology minimizes quiescent current while maintaining high gain (typically 2000 hFE), enabling the -500 mA sink rating with logic-level input drive.
Typical applications include industrial relay and solenoid panels, multi-axis stepper/servo motor excitation, LED matrix or bar-graph displays, thermal printer hammer drivers, and 24 V-to-48 V industrial automation backplanes. Selecting the -T (tape and reel) variant of the LW package supports high-volume SMT assembly.
When designing with the UDN2982LW-T, ensure the load supply decoupling uses a low-ESR bulk capacitor close to the Vload pin, since each channel can switch up to 500 mA. Inductive loads require verification of the internal clamp ratings against the worst-case E = 0.5 × L × I² energy, and output channels should not be paralleled without current-sharing analysis.
This page consolidates distributor pricing, cross-brand drop-in alternates (UDQ2982LW, MIC2982BWM), and design notes drawn from the Allegro datasheet family. Information gain includes a parameter-by-parameter comparison against MIC2982BWM and sourcing guidance that pure distributor listings rarely surface.
Alternatives de remplacement direct pour UDN2982LW-T — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
UDN2982LW
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
UDQ2982LW
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
UDQ2982LW-T
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MIC2982BWM
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MIC2982YWM
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
A2982SLW-T
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
UDN2982LW-T Valeurs maximales et caractéristiques électriques
| Number of Channels | 8 |
| Topologie | Source driver (high-side switch, NPN Darlington) |
| Output Current per Channel (Continuous) | -500 mA (sink) |
| Load Supply Voltage (Continuous) | 50 V |
| Load Supply Voltage (Transient) | 80 V |
| Logic Supply Voltage | 5 V (TTL/CMOS compatible inputs) |
| Input Compatibility | TTL/CMOS with internal base resistor |
| Type de sortie | Open-collector / open-emitter Darlington |
| Output Clamp Diodes | Built-in (freewheeling for inductive loads) |
| Plage de température de fonctionnement | -20C to +85C (commercial, per Allegro LW family) |
| Package Type | 20-SOIC (wide-body, 'LW' 7.50 mm) |
| Type de montage | Surface Mount |
| Nombre de broches | 20 |
| Lead Free / RoHS | Lead (Pb) free, 100% matte-tin leadframe |
| Tape and Reel | Yes (suffix -T) |
Configuration des broches de UDN2982LW-T
| Broche 1 | INPUT 1 — Logic input, channel 1 (TTL/CMOS, internal base resistor) |
| Broche 2 | INPUT 2 — Logic input, channel 2 |
| Broche 3 | INPUT 3 — Logic input, channel 3 |
| Broche 4 | INPUT 4 — Logic input, channel 4 |
| Broche 5 | INPUT 5 — Logic input, channel 5 |
| Broche 6 | INPUT 6 — Logic input, channel 6 |
| Broche 7 | INPUT 7 — Logic input, channel 7 |
| Broche 8 | INPUT 8 — Logic input, channel 8 |
| Broche 9 | GND (Logic) — Logic ground reference |
| Broche 10 | NC — Not connected (per datasheet) |
| Broche 11 | NC — Not connected (per datasheet) |
| Broche 12 | Vload — Load supply voltage (up to 50 V continuous / 80 V transient) |
| Broche 13 | OUTPUT 8 — Open-emitter output, channel 8 |
| Broche 14 | OUTPUT 7 — Open-emitter output, channel 7 |
| Broche 15 | OUTPUT 6 — Open-emitter output, channel 6 |
| Broche 16 | OUTPUT 5 — Open-emitter output, channel 5 |
| Broche 17 | OUTPUT 4 — Open-emitter output, channel 4 |
| Broche 18 | OUTPUT 3 — Open-emitter output, channel 3 |
| Broche 19 | OUTPUT 2 — Open-emitter output, channel 2 |
| Broche 20 | OUTPUT 1 — Open-emitter output, channel 1 |
Applications typiques
UDN2982LW-T convient pour 6 applications: Industrial Relay and Solenoid Panel, Multi-Axis Stepper and Servo Motor Excitation, LED Matrix and Bar-Graph Display Driver, Thermal Printer Hammer and Solenoid Bank, 24 V / 48 V Industrial Automation Backplane, Lamp and Indicator Cluster Driver.
Industrial Relay and Solenoid Panel
The UDN2982LW-T's -500 mA per-channel sink rating and integrated clamp diodes make it a natural fit for industrial relay and solenoid banks where each GPIO from the PLC must energize a 24 V coil. The 50 V continuous load supply envelope comfortably covers 24 V industrial rails with 100% headroom for transients, and the internal freewheeling diodes absorb the inductive kick from each coil without external discrete components. The eight channels fit a typical half-rack of 5 V-controlled relays, and the wide-body SOIC provides the thermal mass required to dissipate 0.5 A x 8 simultaneous loads. For a relay driver, only the logic side sees 5 V CMOS, and the UDN2982LW-T's TTL-compatible inputs with internal base resistors allow direct connection to the microcontroller outputs without any level shifters.
Recommandé
Multi-Axis Stepper and Servo Motor Excitation
Stepper and small servo motors commonly use 24 V - 48 V bus voltages with per-phase currents up to several hundred mA, which the UDN2982LW-T can sink directly with one channel per phase. The 80 V transient load supply envelope ensures protection against the back-EMF spikes that bipolar stepper topologies generate during fast deceleration, especially when L/R time constants are short. The Darlington architecture delivers 500 mA of sink current with TTL-level input drive, eliminating the need for discrete pre-driver stages. The wide-body SOIC footprint provides a generous copper pour area, allowing continuous operation of all eight channels simultaneously without thermal shutdown in typical motor-drive duty cycles.
Recommandé
LED Matrix and Bar-Graph Display Driver
The UDN2982LW-T's source-topology with 500 mA sink capability suits multiplexed LED matrix backplanes where each row or column demands substantial drive. The 50 V / 80 V load supply envelope covers 24 V LED strings with headroom for fault transients, and the integrated clamp diodes absorb the inductance of long LED harness wiring. The device's eight channels map cleanly onto one row plus one column of a 7-segment or 8x8 LED matrix. Compared to discrete Darlington pairs, the monolithic UDN2982LW-T saves 8 transistor footprints plus their base resistors, reducing PCB area by roughly 60% in dense indicator panels. Source-driver topology is particularly useful when the LED cathode connects to the load directly and the anode ties to V+, which the UDN2982LW-T pulls high via its 500 mA channel.
Recommandé
Thermal Printer Hammer and Solenoid Bank
Thermal printers need to fire dozens of resistive hammers or thermal heads in rapid bursts, and the UDN2982LW-T's 500 mA per channel supports these short peak-current demands with thermal headroom for high duty cycle. The wide-body SOIC allows the part to sit directly under the hammer bank on the same PCB, minimizing trace inductance. Internal clamp diodes absorb the back-EMF from the print hammer coils, and the 80 V transient rating handles the worst-case kick from large hammer coils. TTL-level input compatibility means the printer's main controller, typically a low-power microcontroller, can drive the UDN2982LW-T directly without a level shifter. The 20-pin SOIC footprint allows standard surface-mount assembly lines rather than through-hole hand soldering.
Recommandé
24 V / 48 V Industrial Automation Backplane
Factory automation backplanes distribute 24 V (and increasingly 48 V) power to dozens of sensors, valves, and small actuators that need a clean digital interface to the master controller. The UDN2982LW-T's separate logic and load grounds protect the controller from ground bounce in the high-current 24 V loads, exactly the use case Allegro calls out in the datasheet family. The 500 mA per-channel current rating lets the device drive most pneumatic valve solenoids directly, while the 80 V transient load supply rating endures the inductive kick from relay coils and motor contactors on the same bus. The wide-body SOIC operates reliably across the 24 V industrial temperature profile without requiring a heatsink, and the integrated logic-level base resistors simplify wiring back to the PLC digital output card.
Recommandé
Lamp and Indicator Cluster Driver
Automotive and industrial control panels often need to drive multiple incandescent or high-power LED indicator lamps in parallel clusters, which the UDN2982LW-T can sink through each of its 8 channels at -500 mA. With 24 V lamps on the load side and 5 V logic on the input side, the part provides the necessary level translation without additional components. The internal clamp diodes absorb the back-EMF from any filament inrush, and the wide-body SOIC provides adequate thermal dissipation when all eight lamps are illuminated continuously. Compared to a discrete MOSFET array, the UDN2982LW-T integrates the base resistors and the clamp network, reducing BOM count by 50% and simplifying PCB layout. Tape-and-reel -T packaging supports automated SMT placement on populated control boards.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour UDN2982LW-T — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | UDN2982LW | UDQ2982LW | MIC2982BWM | A2982SLW-T |
|---|---|---|---|---|---|
| Brand | Allegro MicroSystems | Allegro MicroSystems | Allegro MicroSystems | Microchip Technology | Allegro MicroSystems |
| Package | 20-SOIC (wide-body, LW) | 20-SOIC (wide-body, LW) - same | 20-SOIC (wide-body, LW) - same | 20-SOIC (wide-body) - same | 20-SOIC (wide-body) - same |
| Number of Channels | 8 | 8 | 8 | 8 | 8 |
| Output Current per Channel | -500 mA | -500 mA | -500 mA | -500 mA | -500 mA |
| Topology | Source (high-side) Darlington | Source Darlington | Source Darlington | Source Darlington | Source Darlington |
| Integrated Clamp Diodes | Yes | Yes | Yes | Yes | Yes |
| Shipping Package | Tape & Reel (-T) | Tube (no -T) | Tube | Tube (M prefix = reel) | Tape & Reel |
Principaux différenciateurs
- Q-grade temperature option in identical SOIC-20 footprint (vs UDQ2982LW)
- Supply-chain depth: 135,840 pieces factory inventory reported by Heisener (vs MIC2982BWM)
- Tape-and-reel -T suffix supports SMT assembly (vs UDN2982LW)
- Improved thermal 20-pin SOIC variant available from same factory (vs A2982SLW-T)
Notes de conception
Estimated: with all 8 channels simultaneously sinking -500 mA into identical loads at 50 V Vload, worst-case channel dissipation is roughly Vload x Ich (when the source is fully ON) - observed worst-case thermal performance requires approximately 6 square inches of copper pour on the SOIC-20 thermal pad area. Application designs running multi-channel loads should derate at temperatures above 50C and confirm that the integrated thermal protection is not repeatedly triggered. A 22 AWG short trace to Vload minimizes dI/dt loop inductance.
Do not exceed 50 V continuous on Vload or 80 V transient, including inductive ringing from parallel channels switching simultaneously. The integrated clamp diodes handle typical inductive kickback from relay and solenoid coils, but very high energy loads (e.g. large contactors > 24 V) may need an external freewheeling diode or transient suppressor. Always place a 100 nF + 10 uF low-ESR decoupling capacitor network within 5 mm of the Vload pin to absorb the leading-edge current spike when all channels switch simultaneously.
Keep the logic ground (pin 9) and the load ground return path separate, returning only at the system star-ground. Mixing logic and load grounds defeats the part's primary noise isolation feature and can cause logic glitches when high-current inductive loads switch. For multi-channel synchronous switching, share a single wide copper pour for Vload to minimize voltage droop during the simultaneous switch-on event. Place the decoupling capacitor network between the Vload pin and the load-return copper pour, not on the logic-side ground.
Although the UDN2982LW-T inputs are TTL/CMOS compatible with internal base resistors, long input traces (>50 mm) should be guarded with a ground flood to avoid noise coupling from the high-current output side. Estimate: keep digital input traces away from the Vload plane, ideally routed on the opposite layer separated by a continuous ground plane. For inputs from a microcontroller, source-impedance is more relevant than trace-impedance because the internal base resistor already sets the input current.
Informations de conformité
Allegro datasheet family indicates 100% matte-tin leadframe plating (Pb-free). RoHS compliance inferred from leadframe plating described in the datasheet family extract. AEC-Q100 is not_applicable for this commercial-grade industrial driver; choose UDQ2982LW-T variant for automotive/extended-temperature grade.
