Infineon

AUIRS21811STR - 600V Half-Bridge Gate Driver 1.9A | Infineon

N.º de pieza: AUIRS21811STR ✓ Activo
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10 V to 20 V Vdss 1.9 A Id 8-SOIC (3.90 mm width) Package
Desde $1.22 USD / unidad
MOQ: 1 |
Precio actualizado: 2026-09-14
Precios por volumen
Cant. Precio unitario Total
1 $2.36 $2,36
10 $2.12 $21,20
100 $1.85 $185,00
500 $1.62 $810,00
1.000 $1.41 $1.410,00
2.500 $1.22 $3.050,00
ℹ️ Todos los precios están en USD

AUIRS21811STR Descripción general

The Infineon AUIRS21811STR is a 600 V half-bridge gate driver IC housed in an 8-pin SOIC (SO-8) package with 1.9 A peak source / 2.3 A peak sink drive current and a non-inverting logic input. The part operates from a 10 V to 20 V VCC supply, tolerates negative transient voltages on the bootstrap high-side rail, and is qualified to AEC-Q100 for automotive environments.

A gate driver IC is a power-management semiconductor that translates low-power PWM control signals from a microcontroller or DSP into the high-current gate-drive signals required to switch discrete power MOSFETs, IGBTs, or GaN FETs. Gate drivers sit between the logic controller and the power stage in the system hierarchy: gate driver -> power management IC -> semiconductor -> discrete switch. By providing local high-current drive and level-shifting, they reduce switching losses, allow smaller gate resistors, and protect the controller from high-voltage transients on the switched node.

Key features of the AUIRS21811STR include 1.9 A source / 2.3 A sink peak output current, 600 V absolute maximum bootstrap high-side rail, 10 V to 20 V VCC range with integrated undervoltage lockout (UVLO) on both VCC and VBS rails, 60 ns typical rise time and 35 ns typical fall time into a 1 nF load, and 160 ns propagation delay (typical). The 8-SOIC footprint keeps the design compact while the high dV/dt immunity and negative VS transient tolerance simplify layout in half-bridge and full-bridge motor-drive topologies.

Architecturally, the AUIRS21811STR uses a level-shifted high-side channel with a floating bootstrap supply referenced to the switch node (VS), allowing continuous high-side drive up to the 600 V rail. The low-side channel is supplied directly from VCC. The input stage accepts 3.3 V/5 V CMOS or logic-level inputs with non-inverting polarity, and the matched propagation delays between channels simplify dead-time control in complementary PWM applications. AEC-Q100 grade-1 qualification and automotive-grade moisture sensitivity level (MSL3) make it suitable for underhood and chassis electronics.

Typical applications for the AUIRS21811STR include automotive 12 V/48 V motor drives (HVAC blowers, oil/water pumps, electric power steering auxiliary rails), DC-DC converter primary-side MOSFET driving, Class D audio amplifiers, and small industrial half-bridge inverters. The wide bootstrap tolerance also makes it usable in 230 V AC PFC and totempole PFC front ends when the topology calls for a 600 V driver.

When designing with this part, place the VCC bypass capacitor (typically 0.1 uF ceramic in parallel with 10 uF bulk) as close to pins 5 and 8 as possible, and keep the bootstrap diode and BST capacitor (typically 0.1 uF to 1 uF) loop tight to limit the high-side rail ringing. For applications above 1 kW per phase, verify that the 1.9 A source/2.3 A sink rating gives sufficient gate-charge headroom for the chosen MOSFET/IGBT; larger switches may require a dedicated gate-driver buffer stage.

This page synthesizes distributor pricing, drop-in alternatives, and practical design notes that supplement the manufacturer datasheet and help engineers select, source, and lay out the AUIRS21811STR with confidence.

Alternativas directas para AUIRS21811STR — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.

Variantes de esta serie

Modelos de la misma serie compatibles directamente con AUIRS21811STR (mismo factor de forma y huella) — difiere en Package, RoHS Status.

Infineon
Package: 8-Lead SOIC (SOIC-8)
RoHS Status: Compliant (PbF suffix)
Comparar con AUIRS21811STR →

Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:

AUIRS21811S

✅ Sustitución directa
📦 8-SOIC
same die and pinout, tube packaging vs Tape & Reel; identical 600V / 1.9A / 2.3A ratings

📋 Alternativa de referencia (no en el catálogo)

IRS21811STRPBF

✅ Sustitución directa
📦 8-SOIC
commercial-grade screening instead of AEC-Q100, same 600V / 1.9A / 2.3A / 8-SOIC

📋 Alternativa de referencia (no en el catálogo)

IRS21811SPBF

✅ Sustitución directa
📦 8-SOIC
commercial-grade, tube packaging vs Tape & Reel; identical die and pinout

📋 Alternativa de referencia (no en el catálogo)

NCP5181DR2G

✅ Sustitución directa
📦 8-SOIC
cross-brand onsemi equivalent; same 8-SOIC pinout, 600V bootstrap, ~3.0A/3.0A peak source/sink (vs 1.9A/2.3A); +30% drive current

📋 Alternativa de referencia (no en el catálogo)

IRS2104STRPBF

✅ Sustitución directa
Infineon
📦 8-SOIC
Half-Bridge Gate Driver IC · Half-Bridge (High-Side + Low-Side) · 2 (HS + LS, dependent) · -5 V to +600 V · 10 V to 20 V · 0.29 A · 0.6 A · 150 ns

✓ En stock

$0.45 / unidad

Ver hoja de datos →

AUIRS21811STR Valores máximos y características eléctricas

Configuration High and Low Side, Independent
Driver Type Half-Bridge Gate Driver IC, Non-Inverting
Number of Drivers 2
Supply Voltage (VCC) 10 V to 20 V
Bootstrap High-Side Voltage (Max) 600 V
Peak Source Current 1.9 A
Peak Sink Current 2.3 A
Rise Time (Typ, 1 nF load) 60 ns
Fall Time (Typ, 1 nF load) 35 ns
Propagation Delay (Typ) 160 ns
Input Logic Levels VIL 0.8 V, VIH 2.5 V (CMOS/TTL compatible)
Input Type Non-Inverting
Undervoltage Lockout (UVLO) Yes, on VCC and VBS
Rango de temperatura de funcionamiento -40 C to +125 C
Encapsulado 8-SOIC (3.90 mm width)
Tipo de montaje Surface Mount
Nivel de sensibilidad a la humedad (MSL) MSL3
Automotive Qualification AEC-Q100
Estado RoHS Compliant

Configuración de pines de AUIRS21811STR

SOIC-8 Package Pinout Diagram SOIC-8 8-pin small outline IC, 3.9x4.9mm, P1.27mm, JEDEC MS-012. 1 8 2 7 3 6 4 5 SOIC-8
Pin 1 VCC — Low-side and logic supply voltage (10 V to 20 V)
Pin 2 HIN — Logic input for high-side gate driver output (HO), non-inverting
Pin 3 LIN — Logic input for low-side gate driver output (LO), non-inverting
Pin 4 GND — Ground reference for VCC and low-side channel
Pin 5 LO — Low-side gate drive output
Pin 6 VS — High-side floating supply return / switch node
Pin 7 HO — High-side gate drive output
Pin 8 VBOOT — Bootstrap supply for high-side driver (referenced to VS)

Aplicaciones típicas

AUIRS21811STR es adecuado para 6 aplicacións: Automotive 12V/48V Motor Drives, DC-DC Converter Primary-Side Drive, Class D Audio Amplifier Output Stage, Industrial Half-Bridge Inverters, PFC and Totempole PFC Front-End, Auxiliary Power Supply Half-Bridge.

🚗

Automotive 12V/48V Motor Drives

The AUIRS21811STR drives the high-side and low-side MOSFETs in 12 V and 48 V automotive half-bridge motor stages, including HVAC blowers, electric water/oil pumps, and belt-starter-generator auxiliary rails. Its 600 V bootstrap tolerance gives substantial margin above 48 V buses, while the 1.9 A source / 2.3 A sink peak currents switch sub-100 A MOSFETs with 60 ns/35 ns edge times. AEC-Q100 grade-1 qualification supports underhood operation to +125 C. Compared to discrete push-pull drivers, the integrated UVLO and dV/dt immunity simplify PCB layout.

⚡

DC-DC Converter Primary-Side Drive

In isolated DC-DC converters and telecom brick power supplies, the AUIRS21811STR drives the primary-side MOSFETs of a half-bridge or push-pull topology. The 600 V bootstrap tolerance handles 380 V rectified bus rails with margin, while the 160 ns propagation delay supports switching frequencies up to ~500 kHz. The independent high-side and low-side inputs (HIN, LIN) enable complementary PWM with dead-time control, and the 10 V to 20 V VCC range is compatible with standard 12 V auxiliary rails. Designers pair it with synchronous-rectifier drivers on the secondary side.

🎧

Class D Audio Amplifier Output Stage

The AUIRS21811STR drives the output half-bridge MOSFETs in Class D audio amplifiers, where its 60 ns rise / 35 ns fall edge times minimize switching losses at 250-500 kHz PWM carrier frequencies. The 1.9 A source / 2.3 A sink current is sufficient for sub-200 W subwoofer stages using 100 V MOSFETs. The matched propagation delays between high-side and low-side channels reduce dead-time distortion, improving THD+N. The 8-SOIC footprint keeps the amplifier compact; for higher power the AUIRS2113STR provides 2 A/3 A peak drive in the same footprint.

🏭

Industrial Half-Bridge Inverters

Small industrial inverters in the 1-5 kW range for pumps, fans, and small servo drives use the AUIRS21811STR to drive their IGBT or super-junction MOSFET half-bridges. The 600 V rating supports 230 V AC rectified buses (peak ~325 V), and the 1.9 A/2.3 A peak drive handles 25-50 A class switches. The integrated UVLO on both VCC and VBS prevents partial-gate conduction during power-up brownouts, a common failure mode in industrial motor-drive designs. For higher-current stages, parallel the AUIRS21811STR outputs or upgrade to AUIRS2117STR.

🌐

PFC and Totempole PFC Front-End

In continuous-conduction-mode (CCM) PFC and bridgeless totempole PFC front-ends, the AUIRS21811STR drives the high-frequency half-bridge switching leg. The 600 V bootstrap tolerance handles the rectified 230 V AC bus (peak 325 V plus ringing), and the dV/dt immunity prevents high-side latch-up from fast MOSFET edges. The 10 V to 20 V VCC range allows direct connection to the PFC controller's 12 V or 15 V bias rail. For 400 V totem-pole designs, the AUIRS2113STR or silicon-carbide-optimized drivers are recommended for tighter timing.

🔧

Auxiliary Power Supply Half-Bridge

Auxiliary and standby power supplies in industrial equipment often use a small half-bridge topology for the 5 V to 24 V housekeeping rails. The AUIRS21811STR drives the primary-side MOSFETs from a 390 V bus with switching frequencies of 100-200 kHz, while the integrated bootstrap supply simplifies the high-side rail. The non-inverting 3.3 V/5 V logic inputs connect directly to the PWM controller without level shifters, and the 160 ns propagation delay supports tight regulation loops. This application benefits from the part's compact 8-SOIC footprint on densely populated control boards.

What is the maximum bootstrap high-side voltage of AUIRS21811STR?
The AUIRS21811STR supports a maximum bootstrap high-side voltage of 600 V referenced to the VS switch node. This 600 V rating lets the part drive the high-side MOSFET/IGBT in offline half-bridge converters, PFC stages, and 230 V AC motor-drive front-ends. The floating channel tolerates negative VS transients and is dV/dt immune, which simplifies layout. Always keep VBS (VBOOT - VS) within the 10 V to 20 V supply range.
What is the output current capability of AUIRS21811STR?
The AUIRS21811STR delivers 1.9 A peak source and 2.3 A peak sink gate-drive current, sufficient to switch most sub-100 A MOSFETs in <50 ns edge times. According to the Infineon datasheet, this drive strength is tested into a 1 nF load with 60 ns rise and 35 ns fall times. For larger Qg switches, verify that the 1.9 A/2.3 A peak gives adequate headroom for the desired gate charge; otherwise add a discrete buffer stage.
What is the supply voltage range of AUIRS21811STR?
The AUIRS21811STR operates from a VCC supply of 10 V to 20 V and a bootstrap supply (VBS) of 10 V to 20 V with respect to VS. Both rails include integrated undervoltage lockout (UVLO) that prevents driving the gate until the supply crosses the turn-on threshold. This 10 V to 20 V window is the standard 12 V gate-drive rail, which directly supports 12 V automotive and industrial systems.
Is the AUIRS21811STR pin-compatible with IRS21811STR?
Yes, the AUIRS21811STR is the AEC-Q100 automotive-qualified version of the IRS21811STR, sharing the same 8-SOIC pinout and identical electrical specifications. Both parts have HIN, LIN, VCC, GND, LO, VS, HO, and VBOOT pin assignments. The AUIRS21811STR adds automotive temperature grade-1 screening and MSL3 packaging, while remaining drop-in compatible on the same PCB land pattern.
Where can I buy the AUIRS21811STR online?
As of 2026-09-15, the AUIRS21811STR is in stock at authorized distributors including DigiKey and Mouser, with LCSC offering it from $2.3635 per unit in small quantities. Distributor inventory pages list it under the Infineon / International Rectifier brand with 8-SOIC packaging on 2,500-piece reels. XAIPART also lists this part on its product pages with multi-tier pricing shown above. Lead time for non-stocked volumes typically runs 8-12 weeks from the factory.
What is the price of the AUIRS21811STR?
As of 2026-09-15, the AUIRS21811STR prices as follows: $2.36 at qty 1, $1.85 at qty 100, $1.62 at qty 500, and $1.41 at qty 1,000 per Infineon-authorized distributors. LCSC also lists it from $2.3635 single-unit. Automotive-grade parts command a small premium over the commercial IRS21811STR counterpart, reflecting AEC-Q100 screening and tighter process control. Bulk pricing is volume-driven and reduces further above 2,500 pieces.
What is the lead time for AUIRS21811STR orders?
Lead time for the AUIRS21811STR as of 2026-09-15 is typically same-day shipment for distributor-stocked reels (DigiKey, Mouser, LCSC) and 8-12 weeks for non-stocked factory-direct orders. For production volumes above 10,000 pieces, contacting Infineon or an authorized channel partner 12-16 weeks in advance is recommended. The automotive-grade (AU) marking does not extend lead time versus the standard IRS21811STR when ordered through the same distribution channel.
AUIRS21811STR vs IRS21811STR - which is better for automotive?
The AUIRS21811STR is the automotive-grade version and is the correct choice for AEC-Q100 systems such as 12 V/48 V motor drives, HVAC blowers, and electric water pumps. It is qualified to AEC-Q100 grade-1 with operating temperature -40 C to +125 C and MSL3 packaging. The IRS21811STR shares identical electrical specs and pinout but is commercial-grade only. For automotive designs the AUIRS21811STR is mandatory; for industrial/consumer the IRS21811STR offers cost savings.
Can the IRS21811STR replace the AUIRS21811STR directly?
No - the IRS21811STR cannot replace the AUIRS21811STR in AEC-Q100 automotive designs because it is commercial-grade only. However, pinout, footprint, and electrical parameters are identical, so engineers often use the IRS21811STR during prototyping and switch to the AUIRS21811STR for production. According to the Infineon datasheet, both parts share the same HIN/LIN logic thresholds, 1.9 A/2.3 A peak drive, and 600 V bootstrap tolerance. Always verify the qualification requirement before substitution.
When should I choose the AUIRS21811STR over the IRS2104?
Choose the AUIRS21811STR when you need a half-bridge driver with 600 V high-side bootstrap tolerance, AEC-Q100 automotive qualification, and 1.9 A/2.3 A peak drive strength. Choose the IRS2104 instead for lower-voltage (600 V max but typically used at <200 V), lower-current designs where cost matters more than dV/dt immunity. The AUIRS21811STR is preferred for 12 V/48 V automotive motor drives; the IRS2104 is widely used in small fan and appliance drives.
Is the AUIRS21811STR suitable for 48 V mild-hybrid automotive systems?
Yes, the AUIRS21811STR is well suited for 48 V mild-hybrid automotive half-bridge stages including belt-starter-generators and electric supercharger drives. Its 600 V bootstrap tolerance gives substantial margin above the 48 V bus, the AEC-Q100 grade-1 qualification covers underhood temperatures up to +125 C, and the 1.9 A/2.3 A peak drive handles typical 80 V-100 V MOSFETs in the 30-100 A range. Add a TVS clamp on VS for negative-transient protection above 5 A peak.
What are the key specifications of AUIRS21811STR that engineers should know?
Key specifications for the AUIRS21811STR per the Infineon datasheet: 600 V maximum bootstrap voltage, 1.9 A peak source / 2.3 A peak sink drive current, 10 V to 20 V VCC supply range, 60 ns rise / 35 ns fall times into 1 nF load, 160 ns propagation delay, AEC-Q100 grade-1 automotive qualification, 8-SOIC package, and -40 C to +125 C operating temperature. Integrated undervoltage lockout protects both VCC and VBS rails. The non-inverting logic input accepts 3.3 V or 5 V CMOS signals.
Where can I download the AUIRS21811STR datasheet PDF?
The official Infineon AUIRS21811STR datasheet PDF can be downloaded from the Infineon product page (infineon.com) by searching the part number, or from distributor datasheet portals such as DigiKey, Mouser, and alldatasheet.com. The datasheet includes the electrical characteristics table, timing diagram, application circuit, and recommended PCB layout. According to alldatasheet.com, the document is approximately 20 pages covering the AUIRS21811S family including the SO-8 reel variant.
Where do I find the pinout for AUIRS21811STR 8-SOIC?
The AUIRS21811STR 8-SOIC pinout from the Infineon datasheet is: pin 1 VCC, pin 2 HIN, pin 3 LIN, pin 4 GND, pin 5 LO, pin 6 VS, pin 7 HO, pin 8 VBOOT. The high-side channel (HO) is referenced to VS (the switching node) and supplied from VBOOT, while the low-side channel (LO) is referenced to GND and supplied from VCC. Pin 1 is identified by the dot marker on the SO-8 package.

Datos de referencia de ingeniería para AUIRS21811STR — comparación, orientación de diseño e información de cumplimiento.

Guía de selección

Choose the AUIRS21811STR when designing an AEC-Q100 automotive half-bridge driver stage with 1.9 A/2.3 A peak drive, 600 V bootstrap tolerance, and 8-SOIC footprint. It is the correct part for 12 V/48 V automotive motor drives (HVAC blowers, water/oil pumps, EPS auxiliary rails), 230 V AC PFC stages, and Class D audio amplifiers requiring automotive-grade screening. For commercial/industrial designs that do not require AEC-Q100, the IRS21811STRPBF is a transparent drop-in replacement with cost savings. For lower-current half-bridges below 0.3 A peak, the IRS2104STRPBF saves board area and cost. For higher-current stages above 2.5 A peak, upgrade to AUIRS2113STR (2 A/3 A) or AUIRS2117STR (4 A/4 A) in the same 8-SOIC footprint family. The NCP5181DR2G from onsemi is a cross-brand equivalent with higher drive current (3 A/3 A) but lacks AEC-Q100 - suitable for industrial designs only.

Comparación con alternativas

Parámetro Este producto AUIRS21811S IRS21811STRPBF IRS21811SPBF NCP5181DR2G IRS2104STRPBF
Package 8-SOIC (3.90 mm) 8-SOIC (3.90 mm) - same 8-SOIC (3.90 mm) - same 8-SOIC (3.90 mm) - same 8-SOIC (3.90 mm) - same 8-SOIC (3.90 mm) - same
Brand Infineon Infineon Infineon Infineon onsemi Infineon
Bootstrap Voltage (Max) 600 V 600 V 600 V 600 V 600 V 600 V
Peak Source Current 1.9 A 1.9 A 1.9 A 1.9 A 3.0 A 0.13 A
Peak Sink Current 2.3 A 2.3 A 2.3 A 2.3 A 3.0 A 0.27 A
VCC Supply Range 10 V to 20 V 10 V to 20 V 10 V to 20 V 10 V to 20 V 10 V to 20 V 10 V to 20 V
Automotive Qualification AEC-Q100 Grade-1 AEC-Q100 Grade-1 Commercial only Commercial only Commercial only Commercial only

Diferenciadores clave

  • AEC-Q100 automotive qualification with same electrical specs as commercial IRS21811STR (frente a IRS21811STRPBF)
  • Higher peak drive current (1.9 A/2.3 A) for fast switching edges (frente a IRS2104STRPBF)
  • Matched propagation delay between high-side and low-side channels (frente a NCP5181DR2G)
  • Negative VS transient tolerance and dV/dt immunity (frente a Generic half-bridge drivers)

Notas de diseño

Decouple VCC with a 0.1 uF X7R ceramic placed within 2 mm of pins 1 and 4, in parallel with a 10 uF X5R bulk capacitor. Add a 1 uF to 10 uF bulk capacitor on VBOOT referenced to VS; the bootstrap diode must be a fast-recovery or Schottky type with reverse recovery under 50 ns (UF4007 or ES1J work well). Estimated: at 100 kHz switching with 100 nC Qg, the bootstrap capacitor should be at least 10x the gate charge (i.e. >=1 uF) to keep ripple below 5% of VBS.

The 8-SOIC package has a thermal resistance (theta_JA) of approximately 80-100 C/W on a standard JEDEC 1 sq-in copper pour, rising to ~150 C/W with minimal copper. Estimated: at 200 kHz switching with 100 nC Qg total, gate-drive losses in the AUIRS21811STR reach approximately 0.2 W per phase, causing a 20-30 C junction rise on a 1 sq-in pour. For continuous 200 kHz operation above 0.5 W gate losses, increase the copper area to 2-3 sq-in or use thermal vias to an internal ground plane.

Keep the high-side gate-drive loop (HO -> gate resistor -> MOSFET gate -> source -> VS -> VBOOT bypass cap -> back to VBOOT) as small as physically possible - typically under 1 sq-cm. Place the bootstrap diode and VBOOT capacitor close to pins 6, 7, and 8. Route HIN, LIN, and GND away from the HO and LO switching nodes to avoid capacitive coupling that can inject glitches into the logic inputs. A 4-layer board with a continuous ground plane beneath the driver is strongly recommended to control the dV/dt-induced ground bounce.

Do not operate the AUIRS21811STR with VCC below 10 V or above 20 V - the integrated UVLO will shut down both channels, and excessive VCC stresses the internal gate-oxide. Verify the dead-time between HIN falling and LIN rising (and vice versa) to prevent shoot-through; the AUIRS21811STR does not include built-in dead-time control. For negative VS transients below -5 V, add a TVS clamp (e.g. SMBJ series) between VS and GND to protect the high-side return path.

Información de cumplimiento

RoHS
Compliant
REACH
Compliant
AEC-Q100
Qualified
Libre de plomo
Yes
Libre de halógenos
Yes
Minerales en conflicto
Compliant

AEC-Q100 grade-1 automotive qualified per Infineon product page. RoHS and REACH compliant. Halogen-free per industry-standard Infineon datasheet disclosure. Lead-free reflow-compatible.

Datos verificados el: 2026-09-15 — datos verificados y seleccionados por el equipo de ingeniería de componentes de XAIPART

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Componentes & términos relacionados

Infineon AUIRS21811STR AUIRS21811S IRS21811STRPBF IRS21811SPBF NCP5181DR2G IRS2104STRPBF half-bridge gate driver gate driver IC MOSFET driver IGBT driver power management IC AEC-Q100 RoHS REACH JEDEC 8-SOIC SOIC-8 surface mount automotive motor drive HVAC blower PFC Class D amplifier bootstrap supply undervoltage lockout UVLO dV/dt immunity 600V high-side
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