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Renesas ISL9440CIRZ-T
- Part No.:
- ISL9440CIRZ-T
- Manufacturer:
- Renesas
- Category:
- Voltage Regulators - Linear + Switching
- Package:
- 32-VFQFN Exposed Pad
- Datasheet:
-
ISL9440CIRZ-T.pdf
- Description:
- IC REG QUAD BUCK/LNR SYNC 32QFN
- Quantity:
- Payment:
- Shipping:
Inventory:3,372
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Product details
Overview
ISL9440CIRZ-T from Renesas Electronics (formerly Intersil) is a quad-output power management IC integrating three synchronous buck PWM controllers and one low-dropout linear regulator controller, designed for multi-rail power delivery in home connectivity and industrial applications. It operates at 600kHz switching frequency, supports 0.8V adjustable output down to 0.8V per rail, delivers programmable soft-start via EN/SS pins, and includes integrated UV/OV/OC/OT protection in a 32-lead 5mm×5mm QFN package.
For engineers reviewing the ISL9440CIRZ-T datasheet, ISL9440CIRZ-T pinout, ISL9440CIRZ-T application, or ISL9440CIRZ-T equivalent, key selection considerations include its 600kHz fixed-frequency current-mode control, out-of-phase (0°/180°/0°) PWM phase alignment for reduced input ripple, adaptive shoot-through protection, pre-biased startup capability, and early warning logic output triggered by VIN falling below 5.55V.
Technical Context
The ISL9440CIRZ-T implements current-mode PWM control with voltage feed-forward compensation across all three buck channels, enabling stable operation without external compensation components. Its 600kHz switching frequency (522–678kHz range) and 0°/180°/0° phase interleaving reduce RMS input current and input capacitor stress.
Each buck channel uses internal bootstrap diodes and MOSFET rDS(ON)-based current sensing-eliminating external sense resistors-while the LDO controller drives PNP BJTs or P-channel MOSFETs with 0.8V reference accuracy and 50mA sink capability on the G4 output.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switching Frequency | 600kHz (522–678kHz range); enables smaller magnetics and higher power density vs 300kHz variants. |
| Output Voltage Range | Adjustable down to 0.8V per rail; supports modern low-voltage SoCs and FPGAs requiring precise multi-rail sequencing. |
| Input Voltage Range | 5.6V–24V (VIN pin) or 4.5V–5.6V (VCC_5V pin); dual-supply flexibility for 5V-input systems with VIN tied to VCC_5V. |
| Soft-Start Current | 1.55µA (typical) into EN/SSx pins; sets programmable ramp time via external capacitor for controlled inrush current. |
| Early Warning Threshold | VIN < 5.55V (typical) triggers PGOOD low; provides system-level data backup signal before brownout. |
| Thermal Shutdown | 150°C with 20°C hysteresis; protects against sustained overload or poor PCB thermal design. |
| Package | 32-lead 5mm×5mm QFN (L32.5x5B); exposes thermal pad for efficient heat dissipation in compact layouts. |
Pinout & Package
ISL9440CIRZ-T is housed in a 32-lead, 5mm×5mm QFN package with exposed thermal pad (PKG DWG # L32.5x5B), RoHS-compliant matte tin termination, and MSL3 rating.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| EN/SS1, EN/SS2, EN/SS3 (Pins 5,14,17) | Independent enable & soft-start inputs | Each controls one buck rail; 1.55µA internal charge current enables programmable start-up timing and supply sequencing. |
| FB1, FB2, FB3, LDOFB (Pins 6,13,16,10) | Feedback voltage inputs | Set output voltage via resistor dividers; also used by PGOOD circuit to monitor regulation status (±10% for PWM, ±25% for LDO). |
| ISEN1, ISEN2, ISEN3 (Pins 1,24,18) | Current-sense inputs | Monitor lower-MOSFET rDS(ON) voltage drop for cycle-by-cycle overcurrent protection-no external sense resistor required. |
| UGATE1–3 / LGATE1–3 (Pins 30,27,21 / 29,28,22) | High-side & low-side gate drivers | Drive external N-channel MOSFETs; UGATE channels deliver 800mA source/2A sink (Ch1–2), 400mA (Ch3); LGATE drives matched low-side switches. |
| BOOT1–3 (Pins 31,26,20) | Bootstrap supply pins | Internally integrate bootstrap diodes-reducing BOM count and layout complexity for high-side gate drive. |
| PGOOD (Pin 2) | Open-drain power-good indicator | Asserts low if any PWM output deviates >±10%, LDO output drops <75%, or VIN falls <5.55V-enabling system reset coordination. |
| RST (Pin 8) | Reset pulse output | Asserts low 5.5µs after PGOOD falls; provides synchronized system reset without external timing components. |
| G4 (Pin 9) | LDO controller output | Open-drain output driving base/gate of external PNP or P-MOSFET; supports ultra-low dropout regulation with 50mA sink capability. |
Key Features
| Feature | Design Value |
|---|---|
| Triple 600kHz Synchronous Buck Controllers | Enables compact, high-efficiency multi-rail designs with reduced EMI and input capacitance requirements via 0°/180°/0° phase interleaving. |
| No External Current Sense Resistor | Leverages MOSFET rDS(ON) for current sensing-eliminates power loss and board space associated with discrete sense resistors. |
| Programmable Soft-Start per Rail | Independent EN/SSx pins with 1.55µA charge current allow precise control of inrush current and power-up sequencing across four outputs. |
| Integrated Early Warning Function | Dedicated logic-level output (via PGOOD) triggered by VIN <5.55V enables host MCU to initiate safe data backup before brownout. |
| Adaptive Shoot-Through Protection | Prevents simultaneous conduction of high- and low-side MOSFETs-ensuring robust operation across temperature and process variations. |
| Internal 5V LDO with 60mA Output | Powers internal circuitry, gate drivers, and boot capacitors; eliminates need for external bias supply in most designs. |
Applications
| Satellite & Cable Set-Top Boxes | Cable Modems |
|---|---|
Use Scenario: Powering multiple SoC rails (core, I/O, memory, tuner) from a single 12V or 19V DC input. IC Role / Device Role / Timing Role: Quad-output PMIC delivering sequenced 1.0V, 3.3V, 5.0V, and 2.5V supplies with independent enable control and 600kHz switching. Use Value: Reduces input ripple and capacitor count via 0°/180°/0° phase alignment-critical for EMI-constrained RF-sensitive enclosures. | Use Scenario: Generating isolated 3.3V, 5.0V, and 12V rails for Ethernet PHY, DOCSIS chipset, and front-panel LEDs from 12V input. IC Role / Device Role / Timing Role: Three synchronous buck regulators + LDO controller providing regulated outputs with programmable soft-start and early warning for brownout recovery. Use Value: Pre-biased startup capability ensures clean power-up even when auxiliary rails are already active-avoiding latch-up during hot-plug events. |
| VoIP Gateway Devices | ATX Power Supply Auxiliary Rails |
Use Scenario: Delivering 1.2V CPU core, 3.3V I/O, and 5.0V analog rails while supporting rapid wake-from-sleep transitions. IC Role / Device Role / Timing Role: Multi-rail controller with independent EN/SS pins enabling precise power sequencing and fast dynamic response to load transients. Use Value: 600kHz operation allows use of smaller inductors and ceramic capacitors-reducing solution size and cost in space-constrained VoIP chassis. | Use Scenario: Providing tightly regulated +3.3V, +5VSB, and +12V standby rails in ATX-compliant power supplies with minimal component count. IC Role / Device Role / Timing Role: High-efficiency triple buck controller with integrated LDO for auxiliary rail generation and system monitoring via PGOOD/RST signals. Use Value: Integrated early warning and reset functions eliminate need for external supervisor ICs-simplifying BOM and improving reliability. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar multi-rail power management applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ISL9440IRZ | Fixed 300kHz switching frequency; no programmable soft-start (1.7ms fixed); same 32-pin QFN package and pinout. | Lower switching loss at light loads but requires larger magnetics; less flexible sequencing for complex SoC power trees. | Select ISL9440IRZ only when 300kHz operation and fixed soft-start meet system EMI and startup timing requirements. |
| RTQ2132BGQW | 3-channel 600kHz buck + LDO; integrates MOSFETs (not controllers); 4mm×4mm WQFN-28; no early warning function. | Reduced external component count but limited output current scalability; lacks VIN-fail detection and system-level reset coordination. | Choose RTQ2132BGQW for cost-sensitive, lower-current applications where integrated FETs simplify layout-but not for high-power or safety-critical brownout response. |
Compared with ISL9440IRZ, ISL9440CIRZ-T offers faster transient response and smaller passive components due to 600kHz operation, while RTQ2132BGQW trades external FET flexibility and early warning capability for integration density-making ISL9440CIRZ-T optimal for performance-driven, multi-rail industrial and connectivity designs requiring robust fault signaling.
Availability
ISL9440CIRZ-T is available at Aetrix Electronics and suitable for satellite set-top boxes, cable modems, VoIP gateways, and ATX auxiliary power applications requiring stable component supply, long-term lifecycle support, and traceable sourcing.
Supply support for ISL9440CIRZ-T 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 Corporation is a global semiconductor leader delivering trusted embedded design innovation, with deep expertise in power management, microcontrollers, and analog solutions.
The ISL9440CIRZ-T belongs to Renesas' high-density multi-rail PMIC product line, engineered specifically for home networking, broadband access, and industrial edge devices needing reliable, sequenced, and fault-aware power delivery.
FAQ
What is the switching frequency of the ISL9440CIRZ-T and how does it impact design?
The ISL9440CIRZ-T operates at a fixed 600kHz switching frequency (522–678kHz range). This enables smaller inductors and output capacitors versus 300kHz alternatives, reducing solution size and cost. Higher frequency also improves transient response but increases switching losses-requiring careful MOSFET selection and thermal management. The device's current-mode control with voltage feed-forward maintains stability across input voltage variations without external compensation.
Does the ISL9440CIRZ-T support independent power sequencing across its four outputs?
Yes, the ISL9440CIRZ-T provides independent enable and soft-start control for each of its three buck regulators via EN/SS1, EN/SS2, and EN/SS3 pins. Each pin sources a precise 1.55µA current to charge an external capacitor, allowing programmable delay and ramp time. The LDO controller (G4 output) is enabled synchronously with the first buck rail unless externally gated-supporting complex power-up/down sequences required by modern SoCs and FPGAs.
How does the ISL9440CIRZ-T implement overcurrent protection without an external sense resistor?
The ISL9440CIRZ-T uses the rDS(ON) of the external low-side MOSFET as the current-sense element. Voltage across the MOSFET during conduction is monitored at the ISEN1, ISEN2, and ISEN3 pins. An internal comparator compares this to a threshold set by the OCSETx pin voltage (1.75V typical), triggering cycle-by-cycle current limiting. This eliminates power loss and board area associated with discrete sense resistors while maintaining accurate current monitoring.
What is the purpose of the early warning function in the ISL9440CIRZ-T and how is it implemented?
The early warning function in the ISL9440CIRZ-T monitors the VIN pin and asserts PGOOD low when voltage drops below 5.55V (typical), providing advance notification of impending brownout. This allows the host system to save critical data before power loss. Unlike standard PGOOD (which monitors output regulation), this feature directly ties to input supply health-enabling robust system-level fault handling without external supervisors or comparators.
Can the ISL9440CIRZ-T operate from a 5V input supply, and what configuration is required?
Yes, the ISL9440CIRZ-T supports 5V ±10% input operation. In this mode, the VCC_5V pin must be used as the primary supply input and externally connected to the VIN pin. This disables the internal 5V LDO and powers the IC directly from the 5V rail. The device maintains full functionality-including all protections, soft-start, and PGOOD-while reducing internal power dissipation and simplifying biasing in low-input-voltage systems.
ISL9440CIRZ-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 32-VFQFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- 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)
ISL9440CIRZ-T FAQ
1.How can I place an order for ISL9440CIRZ-T through Aetrix?
Please submit a Request for Quotation (RFQ) for ISL9440CIRZ-T 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 ISL9440CIRZ-T reliable?
The price and inventory of ISL9440CIRZ-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ISL9440CIRZ-T is usually 5 days.
3.What payment methods are accepted for ISL9440CIRZ-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ISL9440CIRZ-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ISL9440CIRZ-T?
ISL9440CIRZ-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ISL9440CIRZ-T 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 ISL9440CIRZ-T?
For technical support, including ISL9440CIRZ-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ISL9440CIRZ-T requirements.
6.How does Aetrix verify that ISL9440CIRZ-T is sourced from the original manufacturer or authorized distributors?
All ISL9440CIRZ-T 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 ISL9440CIRZ-T meets industry standards.
7.What is the process for return or replacement of ISL9440CIRZ-T?
All ISL9440CIRZ-T units undergo pre-shipment inspection (PSI). If there is an issue with ISL9440CIRZ-T, 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 ISL9440CIRZ-T part is unused and in its original packaging.
Return procedure for ISL9440CIRZ-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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