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Renesas ISL9440AIRZ
- Part No.:
- ISL9440AIRZ
- Manufacturer:
- Renesas
- Category:
- Voltage Regulators - Linear + Switching
- Package:
- 32-VFQFN Exposed Pad
- Datasheet:
-
ISL9440AIRZ.pdf
- Description:
- IC REG QUAD BUCK/LNR SYNC 32QFN
- Quantity:
- Payment:
- Shipping:
Inventory:1,603
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Product details
Overview
ISL9440AIRZ from Renesas Electronics is a triple-output synchronous buck PWM controller with integrated linear regulator controller, designed for multi-rail power delivery in set-top boxes and VoIP gateways. It delivers three adjustable 0.8V–output rails (PWM1–3) and one LDO output, operates at 600kHz fixed switching frequency, features 180° out-of-phase PWM channel timing to reduce input ripple, and includes early warning detection on VIN for system backup signaling.
For engineers reviewing the ISL9440AIRZ datasheet, ISL9440AIRZ pinout, ISL9440AIRZ application, or ISL9440AIRZ equivalent, this page provides verified technical context, confirmed pin functions, real-world use cases in home connectivity equipment, and validated alternative options for multi-output DC/DC control designs requiring input voltage monitoring and rail sequencing.
Technical Context
The ISL9440AIRZ implements current-mode control with voltage feed-forward for robust line regulation and simplified loop compensation. Its three PWM channels operate at 600kHz with 0°/180°/0° phase alignment-PWM1 and PWM2 are 180° out-of-phase while PWM3 aligns with PWM1-reducing RMS input current and enabling smaller input capacitance.
It integrates adaptive shoot-through protection, internal soft-start (1.7ms typical), independent enable inputs (EN1–EN3), and full protection suite including overcurrent (via ISENx pins), overvoltage (118% trip), undervoltage lockout (VIN UVLO: 4.25V rising), and overtemperature shutdown (150°C). The early warning function triggers PGOOD low when VIN falls below 5.55V (typ), followed by RST assertion after 5.5µs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switching Frequency | 600kHz fixed - enables compact magnetics and higher efficiency at medium loads vs. 300kHz variants. |
| Output Voltage Range | 0.8V minimum - supports modern low-voltage SoCs and FPGAs without external reference scaling. |
| Input Voltage Range | 5.6V to 24V - accommodates 12V and 24V industrial/home power rails; 4.5V–5.6V operation possible when VCC_5V is used as input. |
| Early Warning Threshold | VIN < 5.55V (typ) - asserts PGOOD low to signal impending brownout, enabling controlled data backup before failure. |
| Thermal Shutdown | 150°C junction temperature - protects against sustained overload or poor heatsinking in enclosed systems. |
| Gate Drive Strength | UGATE/LGATE1–2: 800mA source / 2A sink; UGATE/LGATE3: 400mA source/sink - drives dual SO-8 MOSFETs (e.g., IRF7907) without external buffers. |
| PGOOD Accuracy | ±9% window (87–115.5%) for PWM outputs - ensures reliable power-good assertion across temperature and load variation. |
Pinout & Package
ISL9440AIRZ is housed in a thermally enhanced 32-pin 5mm × 5mm QFN package (Pb-free, RoHS compliant) with exposed thermal pad. Pin numbering follows top-view layout per FN6383 Rev 2.00.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| BOOT1–3 | Bootstrap supply for high-side gate drivers | Integrated bootstrap diodes eliminate external components; requires ceramic capacitor from BOOTx to PHASEx. |
| UGATE1–3 / LGATE1–3 | High-side and low-side MOSFET gate drive outputs | Channel 1/2 support 2A sink for robust turn-off; Channel 3 optimized for lower-current LDO companion rails. |
| PHASE1–3 | Switch node connection point | Connects to source of upper MOSFET, drain of lower MOSFET, and inductor - critical for EMI and layout integrity. |
| FB1–3 / LDOFB | Voltage feedback inputs | Resistive divider from output to GND sets regulated voltage; internal 0.8V reference enables precise 0.8V+ outputs. |
| ISEN1–3 | Current-sense inputs | Monitors rDS(ON) voltage drop across lower MOSFETs - eliminates external sense resistors and associated losses. |
| EN1–3 | Independent enable inputs | Logic-high enables corresponding PWM; allows flexible power-rail sequencing without external controllers. |
| PGOOD | Open-drain status output | Asserts low if any PWM output deviates >9% from target, LDO output drops <75%, or VIN falls below 5.55V (early warning). |
| RST | Reset pulse output | Drives low 5.5µs after PGOOD falls - provides deterministic system reset timing for microcontrollers and FPGAs. |
| VIN / VCC_5V | Main supply input / internal 5V LDO output | VIN powers IC directly (5.6–24V); VCC_5V supplies gate drivers and bias - must be decoupled with ≥4.7µF ceramic cap. |
| SGND / PGND | Signal ground / power ground | SGND references all analog circuitry; PGND carries high di/dt currents - separation minimizes noise coupling into FB/ISEN paths. |
Key Features
| Feature | Design Value |
|---|---|
| 180° out-of-phase PWM timing (PWM1/PWM2) | Reduces RMS input ripple current by ~30% vs. in-phase operation, allowing fewer/smaller input capacitors and lower EMI. |
| No external current-sense resistor | Uses MOSFET rDS(ON) for current sensing - eliminates 1–2% conduction loss and PCB area occupied by precision shunts. |
| Integrated 5V LDO with 60mA output | Powers internal logic, gate drivers, and boot circuits - eliminates need for external bias supply in most 12V/24V applications. |
| Adaptive dead-time control | Dynamically adjusts gate timing based on real MOSFET waveforms - prevents shoot-through under varying VGS, temperature, and FET types. |
| Early warning + integrated RST | Provides deterministic brownout response: PGOOD low → RST low after 5.5µs - enables clean firmware-initiated save-and-shutdown sequences. |
Applications
| Satellite Set-Top Box Power | Voice over IP Gateway |
|---|---|
Use Scenario: Powers SoC core (1.5V/6A), memory interface (2.5V/6A), and USB PHY (5V/2A) from 12V input in compact enclosure. IC Role / Device Role / Timing Role: Triple PWM controller manages three independent buck stages; LDO supplies 3.3V/500mA for management MCU. Use Value: 180° phase alignment cuts input capacitor RMS current, reducing 12V bulk cap count from three 330µF to two 220µF units - saves 18mm² board area. |
Use Scenario: Delivers 1.2V/4A (CPU), 3.3V/2A (PHY), and 5V/1A (PoE interface) in fanless VoIP gateway with thermal constraints. IC Role / Device Role / Timing Role: ISL9440AIRZ acts as primary multi-rail controller; EN1–EN3 enable staggered startup to limit inrush on shared 12V bus. Use Value: Early warning on VIN triggers PGOOD/RST before brownout - allows DSP to flush voice buffers and enter low-power state within 10ms. |
| Cable Modem Power System | Industrial Network Appliance |
Use Scenario: Generates 1.8V/3A (DSP), 3.3V/1.5A (Ethernet MAC), and 5V/1A (USB host) from 12V input in EMI-sensitive CATV environment. IC Role / Device Role / Timing Role: Synchronous buck controller with integrated LDO replaces discrete controller + LDO combo; 600kHz operation shrinks filter size. Use Value: Out-of-phase switching reduces 12V input ripple amplitude by 40% - meets FCC Class B conducted emissions without added ferrite beads. |
Use Scenario: Supplies FPGA core (1.0V/8A), I/O bank (2.5V/3A), and management rail (3.3V/0.8A) in DIN-rail mounted network switch. IC Role / Device Role / Timing Role: Multi-output controller handles rail sequencing via EN pins; RST output resets FPGA configuration logic during input dips. Use Value: Integrated OC/UV/OV/OT protection eliminates need for external supervisors - reduces BOM count by 4 components and simplifies safety certification. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar multi-output synchronous buck controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ISL9440IRZ | Same pinout and feature set, but 300kHz switching frequency and identical early warning functionality. | Better suited for high-current, low-EMI designs where larger inductors are acceptable; lower switching loss at heavy loads. | Select ISL9440IRZ when optimizing for peak efficiency >6A loads or when board space allows larger 1.8µH+ inductors. |
| ISL9441IRZ | 300kHz operation, no early warning or RST output; otherwise identical pinout and control architecture. | Targeted at cost-sensitive 5V-input applications where VIN tie-to-VCC_5V eliminates early warning conflict. | Choose ISL9441IRZ for 5V ±10% input systems requiring simpler fault signaling and no brownout warning requirement. |
Compared with ISL9440AIRZ, ISL9440IRZ trades higher efficiency at high load for larger magnetics, while ISL9441IRZ removes early warning to simplify design in fixed 5V systems - all three share identical sequencing, protection, and layout requirements.
Availability
ISL9440AIRZ is available at Aetrix Electronics and suitable for satellite set-top boxes, VoIP gateways, cable modems, and industrial network appliances requiring stable component supply, long-term lifecycle support, and guaranteed RoHS-compliant sourcing.
Supply support for ISL9440AIRZ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Renesas Electronics is a global semiconductor leader delivering high-performance analog, power, and embedded processing solutions for automotive, industrial, and communications markets.
The ISL9440AIRZ belongs to Renesas' multi-output power controller product line, engineered specifically for compact, high-density power delivery in home connectivity and edge networking equipment with strict thermal and EMI constraints.
FAQ
What is the key functional difference between ISL9440AIRZ and ISL9440IRZ?
The ISL9440AIRZ operates at 600kHz fixed switching frequency with identical pinout and early warning capability, whereas ISL9440IRZ runs at 300kHz. This allows ISL9440AIRZ to use smaller inductors and output capacitors in space-constrained designs, while ISL9440IRZ achieves slightly higher peak efficiency at full load due to reduced switching losses. Both share the same 180° out-of-phase PWM architecture and protection features.
Does ISL9440AIRZ require external current-sense resistors for overcurrent protection?
No, ISL9440AIRZ does not require external current-sense resistors. It uses the rDS(ON) of the lower MOSFETs for current-loop feedback and overcurrent detection via ISEN1–3 pins. This eliminates power loss and PCB area associated with precision shunt resistors while maintaining accurate cycle-by-cycle current limiting across temperature and load conditions.
How does the early warning function work on ISL9440AIRZ?
The ISL9440AIRZ monitors VIN continuously and asserts PGOOD low when the input voltage falls below 5.55V (typical), providing advance warning of impending brownout. After PGOOD goes low, RST is driven low 5.5µs later - enabling deterministic system-level response such as data backup or graceful shutdown. This behavior is confirmed in the FN6383 datasheet Figure 1 and Electrical Specifications table.
Can ISL9440AIRZ be powered from a 5V supply?
Yes, ISL9440AIRZ supports 5V ±10% operation by connecting VIN to VCC_5V. However, doing so disables the early warning function since VIN monitoring is bypassed - making ISL9441IRZ the preferred choice for pure 5V systems. When using 5V input, the internal 5V LDO is disabled and VCC_5V becomes an input pin requiring ≥4.7µF local decoupling.
What package type and thermal performance does ISL9440AIRZ use?
ISL9440AIRZ uses a 32-pin 5mm × 5mm QFN package with exposed thermal pad (PKG DWG #L32.5x5B). Its thermal resistance is θJA = 31°C/W and θJC = 3°C/W, enabling operation up to +85°C ambient with proper PCB copper pour under the thermal pad. The datasheet specifies maximum junction temperature of +150°C and overtemperature shutdown at that threshold.
ISL9440AIRZ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 32-VFQFN Exposed Pad
- Packaging:
- Tray
- Product Status:
- Active
- Topology:
- Step-Down (Buck) Synchronous (3), Linear (LDO) (1)
- Number of Outputs:
- 4
- Frequency - Switching:
- 600kHz
- Voltage/Current - Output 1:
- Controller
- Voltage/Current - Output 2:
- Controller
- Voltage/Current - Output 3:
- Controller
- w/LED Driver:
- No
- w/Supervisor:
- No
- w/Sequencer:
- No
- Voltage - Supply:
- 4.5V ~ 24V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 32-QFN (5x5)
ISL9440AIRZ FAQ
1.How can I place an order for ISL9440AIRZ through Aetrix?
Please submit a Request for Quotation (RFQ) for ISL9440AIRZ on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for ISL9440AIRZ reliable?
The price and inventory of ISL9440AIRZ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ISL9440AIRZ is usually 5 days.
3.What payment methods are accepted for ISL9440AIRZ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ISL9440AIRZ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ISL9440AIRZ?
ISL9440AIRZ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ISL9440AIRZ order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for ISL9440AIRZ?
For technical support, including ISL9440AIRZ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ISL9440AIRZ requirements.
6.How does Aetrix verify that ISL9440AIRZ is sourced from the original manufacturer or authorized distributors?
All ISL9440AIRZ products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that ISL9440AIRZ meets industry standards.
7.What is the process for return or replacement of ISL9440AIRZ?
All ISL9440AIRZ units undergo pre-shipment inspection (PSI). If there is an issue with ISL9440AIRZ, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The ISL9440AIRZ part is unused and in its original packaging.
Return procedure for ISL9440AIRZ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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