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Renesas ISL9440CIRZ
- Part No.:
- ISL9440CIRZ
- Manufacturer:
- Renesas
- Category:
- Voltage Regulators - Linear + Switching
- Package:
- 32-VFQFN Exposed Pad
- Datasheet:
-
ISL9440CIRZ.pdf
- Description:
- IC REG QUAD BUCK/LNR SYNC 32QFN
- Quantity:
- Payment:
- Shipping:
Inventory:1,136
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Product details
Overview
ISL9440CIRZ from Renesas (formerly Intersil) is a quad-output multi-rail power controller integrating three synchronous buck PWM controllers and one low-dropout linear regulator controller. It delivers 0.8V–12V programmable outputs, operates at 600kHz switching frequency, supports independent enable/soft-start sequencing, and provides full protection (UV/OV/OC/OT) in a 32-lead 5mm×5mm QFN package for home connectivity and industrial power systems.
For engineers reviewing the ISL9440CIRZ datasheet, ISL9440CIRZ pinout, ISL9440CIRZ application, or ISL9440CIRZ equivalent, this page details its out-of-phase PWM architecture, internal LDO biasing, early warning input monitoring, and design-critical gate drive specifications - all validated for set-top box, cable modem, and ATX auxiliary rail use cases.
Technical Context
The ISL9440CIRZ implements current-mode control with voltage feed-forward ramp modulation to reject input transients and simplify loop compensation. Its three PWM channels operate at fixed 600kHz with 0°/180°/0° phase alignment to minimize RMS input current and reduce bulk capacitor requirements.
Each buck channel uses MOSFET rDS(ON) sensing for current-loop feedback-eliminating external sense resistors-and features adaptive shoot-through protection, pre-biased startup, and cycle-by-cycle current limiting. The integrated linear controller drives PNP BJTs or P-channel MOSFETs with 0.8V reference accuracy and 50mA sink capability on G4.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switching Frequency | 600 kHz (±78 kHz) - enables compact magnetics and high-density layout for space-constrained home gateway PCBs. |
| Output Voltage Range | 0.8 V to 12 V (adjustable via FB divider) - supports core, I/O, and auxiliary rails across diverse SoC platforms. |
| Input Voltage Range | 5.6 V to 24 V (VIN), or 4.5 V to 5.6 V (VCC_5V-powered mode) - accommodates wide-input industrial supplies and 5V-only designs. |
| Internal LDO Output | 5.0 V ±0.5 V @ 60 mA - powers gate drivers, bootstrap circuits, and IC bias; requires ≥4.7 µF local ceramic decoupling. |
| Early Warning Threshold | VIN falling below 5.55 V triggers PGOOD low - provides system-level data backup time before brownout. |
| Thermal Shutdown | 150 °C with 20 °C hysteresis - protects against sustained overload or poor heatsinking in enclosed enclosures. |
| Package | 32-lead 5 mm × 5 mm QFN (L32.5x5B) - RoHS-compliant, exposed thermal pad, MSL3, θJA = 31 °C/W. |
Pinout & Package
ISL9440CIRZ is housed in a 32-lead, 5 mm × 5 mm QFN package with exposed thermal pad (PKG DWG # L32.5x5B). Pin 1 is located at top-left corner (marked "1" on top silkscreen); pin numbering proceeds counterclockwise. Thermal pad must be soldered to PCB ground plane for reliable operation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| BOOT1–BOOT3 | Bootstrap supply for high-side gate drivers | Integrated bootstrap diodes eliminate external diodes; requires 0.1 µF ceramic capacitor to PHASEx per channel. |
| UGATE1–UGATE3 | High-side MOSFET gate drive output | 800 mA source / 2000 mA sink (Ch1/2), 400 mA (Ch3); rise/fall time ≤18 ns into 1000 pF load. |
| LGATE1–LGATE3 | Low-side MOSFET gate drive output | Matches UGATE timing; lower drive impedance enables fast turn-off and shoot-through immunity. |
| PHASE1–PHASE3 | Switch node connection point | Connects to upper MOSFET source, lower MOSFET drain, and output inductor; critical for EMI layout. |
| FB1–FB3, LDOFB | Feedback input for output voltage regulation | 0.8 V reference with ±1% accuracy; 50 nA bias current enables high-resistance dividers for low quiescent loss. |
| EN/SS1–EN/SS3 | Enable + soft-start control input | 1.55 µA internal charge current; voltage threshold 1.3 V enables output; clamps reference during soft-start ramp. |
| PGOOD | Open-drain power-good status indicator | Pulls low if any PWM output deviates >10%, LDO <75% nominal, or VIN <5.55 V; 0.4 V max low-level voltage. |
| RST | Reset pulse output | Asserts low 5.5 µs after PGOOD falls - synchronizes system reset without external timing components. |
Key Features
| Feature | Design Value |
|---|---|
| Triple 600kHz Synchronous Buck Controllers | Out-of-phase (0°/180°/0°) operation reduces input ripple by ~40%, enabling smaller input capacitors and lower EMI. |
| rDS(ON)-Based Current Sensing | Eliminates external current-sense resistors - saves board area, cost, and power loss while maintaining accurate OCP. |
| Programmable Soft-Start per Channel | Independent EN/SSx pins with 1.55 µA charge current allow precise sequencing of up to four rails without external timers. |
| Early Warning Input Monitoring | Detects VIN drop below 5.55 V and asserts PGOOD low - gives host processor time to save state before brownout. |
| Integrated 5V LDO with 60mA Output | Powers internal circuitry, gate drivers, and boot caps; eliminates need for external bias supply in most applications. |
| Complete Protection Suite | Includes UVLO, OV, OC (cycle-by-cycle), OT shutdown, and adaptive dead-time - ensures robust field reliability. |
Applications
| Satellite Set-Top Box Power | Cable Modem Multi-Rail Supply |
|---|---|
|
Use Scenario: Powers SoC core (1.0V/6A), memory I/O (3.3V/6A), and USB PHY (5V/4A) from 12V input in compact enclosure. IC Role / Device Role / Timing Role: Quad-output controller managing rail sequencing, dynamic load response, and brownout warning. Use Value: 600kHz switching enables small inductors; out-of-phase PWM cuts input ripple by 40%, reducing 12V bulk cap size by 30%. |
Use Scenario: Generates 3.3V/15A, 5.0V/15A, and 12V/12A rails plus 2.5V/800mA LDO output from 19V input in VoIP gateway. IC Role / Device Role / Timing Role: Centralized multi-rail PMIC coordinating startup sequence, fault reporting, and thermal management. Use Value: Independent EN/SS pins enable staggered startup to limit inrush; PGOOD/RST signals simplify system-level power sequencing logic. |
| ATX Auxiliary Power | Industrial NAS Controller Board |
|
Use Scenario: Provides +3.3V, +5V, +12V, and +2.5V auxiliary rails for motherboard management controllers and fan drivers. IC Role / Device Role / Timing Role: Replacement for discrete buck controllers with integrated protection and sequencing. Use Value: Single-chip solution reduces BOM count by 12+ components (drivers, sense resistors, references, timers) and improves layout density. |
Use Scenario: Supplies FPGA core (1.0V), DDR3 interface (1.5V), SATA PHY (3.3V), and management MCU (2.5V) in temperature-stressed NAS chassis. IC Role / Device Role / Timing Role: High-reliability power controller with overtemperature hysteresis and early-warning brownout detection. Use Value: 150°C thermal shutdown with 20°C hysteresis prevents latch-up; -40°C to +85°C operating range ensures uptime in unventilated enclosures. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar multi-rail buck controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ISL9440IRZ | Fixed 300kHz switching frequency; non-programmable soft-start time (1.7ms); same pinout and feature set otherwise. | Lower switching loss at light loads; less suitable for ultra-compact layouts requiring high-frequency magnetics. | Select when prioritizing efficiency over size, or when legacy 300kHz design reuse is required. |
| MP2964GL-Z | 4-channel buck controller with digital PMBus interface, 500kHz–1.2MHz programmable frequency, no integrated LDO. | Requires external 5V bias; adds telemetry and dynamic margining but increases firmware complexity. | Select when system-level telemetry, remote configuration, or tighter voltage tolerance (<±0.5%) is mandatory. |
Compared with ISL9440IRZ, ISL9440CIRZ offers higher frequency for smaller passives but slightly higher gate drive losses; versus MP2964GL-Z, it trades digital configurability for analog simplicity and integrated bias - ideal for cost-sensitive, fixed-function embedded power.
Availability
ISL9440CIRZ is available at Aetrix Electronics and suitable for satellite set-top boxes, cable modems, and ATX auxiliary power supplies requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.
Supply support for ISL9440CIRZ 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 acquired Intersil in 2017 and maintains full technical and supply chain support for legacy Intersil power management products.
The ISL9440 family was designed specifically for multi-rail, space-constrained consumer and industrial connectivity devices - emphasizing integration, sequencing flexibility, and robust protection without external components.
FAQ
What is the recommended input capacitor configuration for ISL9440CIRZ in a 12V input application?
For a 12V input, use ≥100µF total bulk capacitance near VIN and PGND pins, supplemented by ≥10µF ceramic (X7R, 1206 or larger) placed within 5mm of each BOOTx–PHASEx pair. The out-of-phase PWM operation allows 30–40% less input capacitance than in-phase alternatives, but low-ESR construction remains critical to sustain 600kHz ripple current.
Does ISL9440CIRZ support pre-biased output startup, and how is it enabled?
Yes, ISL9440CIRZ supports pre-biased output startup on all three PWM channels without external circuitry. It is inherently enabled - the controller monitors FBx voltage during startup and disables gate drive until the feedback signal rises above 0.8V, preventing reverse current flow into pre-charged outputs. No configuration or pin strapping is required.
How does the early warning function of ISL9440CIRZ interact with the PGOOD signal?
The early warning function directly controls PGOOD: when VIN drops below 5.55V (typical falling threshold), PGOOD is pulled low regardless of output regulation status. This provides deterministic system-level warning before brownout. RST then asserts low 5.5µs later, enabling clean reset sequencing - both signals are fully integrated and require no external logic.
Can ISL9440CIRZ drive high-side N-channel MOSFETs without external level shifters?
Yes. ISL9440CIRZ integrates bootstrap diodes and high-current gate drivers (800mA source / 2000mA sink on Ch1/2) optimized for N-channel high-side FETs. Each channel requires only a 0.1µF ceramic bootstrap capacitor between BOOTx and PHASEx. No external level shifter or driver IC is needed for standard silicon MOSFETs with VGS(th) ≤ 2.5V.
What is the maximum allowable thermal resistance for the PCB layout of ISL9440CIRZ?
For continuous operation at full load and 85°C ambient, the PCB must achieve θJA ≤ 31°C/W (per datasheet spec). This requires soldering the exposed thermal pad to ≥4 cm² of inner-layer copper pour connected to ≥6 thermal vias (0.3mm diameter, filled) to internal ground planes. Without adequate thermal relief, junction temperature may exceed 150°C and trigger shutdown.
ISL9440CIRZ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 32-VFQFN Exposed Pad
- Packaging:
- Tube
- 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 FAQ
1.How can I place an order for ISL9440CIRZ through Aetrix?
Please submit a Request for Quotation (RFQ) for ISL9440CIRZ 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 reliable?
The price and inventory of ISL9440CIRZ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ISL9440CIRZ is usually 5 days.
3.What payment methods are accepted for ISL9440CIRZ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ISL9440CIRZ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ISL9440CIRZ?
ISL9440CIRZ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ISL9440CIRZ 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?
For technical support, including ISL9440CIRZ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ISL9440CIRZ requirements.
6.How does Aetrix verify that ISL9440CIRZ is sourced from the original manufacturer or authorized distributors?
All ISL9440CIRZ 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 meets industry standards.
7.What is the process for return or replacement of ISL9440CIRZ?
All ISL9440CIRZ units undergo pre-shipment inspection (PSI). If there is an issue with ISL9440CIRZ, 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 part is unused and in its original packaging.
Return procedure for ISL9440CIRZ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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