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Renesas ISL6840IU
- Part No.:
- ISL6840IU
- Manufacturer:
- Renesas
- Category:
- Power Supply Controllers, Monitors
- Package:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
ISL6840IU.pdf
- Description:
- IC REG CTRLR BOOST/FLYBACK 8MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:2,230
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Product details
Overview
ISL6840IU from Renesas Electronics is a single-ended current mode PWM controller IC designed for boost, flyback, and isolated buck regulators. It delivers 1A peak gate drive, supports up to 2MHz switching frequency, features 60µA start-up current and 100% maximum duty cycle, and operates across –40°C to +105°C in telecom power and industrial DC-DC converter applications.
For engineers reviewing the ISL6840IU datasheet, ISL6840IU pinout, ISL6840IU application, or ISL6840IU equivalent, key selection criteria include UVLO threshold (7.0V), VREF accuracy (±1.0%/–1.5%), CS offset (100mV), COMP-to-PWM delay (25ns), and MSOP-8 package compatibility with layout-sensitive high-frequency power designs.
Technical Context
The ISL6840IU implements peak current mode control with a programmable sawtooth oscillator (RTCT pin), enabling precise frequency and max duty cycle tuning. Its error amplifier provides high open-loop gain (≥60dB) and tight reference voltage tracking (2.514V at FB), supporting stable regulation under line/load/temperature variation.
UVLO hysteresis (0.4V) ensures robust start-up behavior, while the 100mV internal CS offset and 25ns CS-to-OUT propagation delay enable accurate current sensing and fast transient response. The 1A totem-pole output drives MOSFET gates directly with 20ns rise/fall times into 1nF load.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switching Frequency | Up to 2MHz - enables compact magnetics and high-density power supply design. |
| Max Duty Cycle | 100% - supports wide input/output voltage ratios in flyback and boost topologies. |
| VREF Accuracy | ±1.0%/–1.5% over line, load, temperature - ensures stable feedback reference for ±1% output regulation. |
| CS Offset Voltage | 100mV - defines minimum detectable current sense threshold; critical for low-current protection. |
| Start-Up Current | 60µA - minimizes auxiliary supply burden during initial power-up sequence. |
| Peak Output Current | 1.0A - directly drives medium-power MOSFETs without external buffer stages. |
| CS-to-OUT Delay | 25ns - enables fast overcurrent shutdown response for reliable short-circuit protection. |
| Operating Temp Range | –40°C to +105°C - qualified for industrial and telecom base station environments. |
Pinout & Package
ISL6840IU is housed in an 8-lead MSOP package (M8.118), optimized for thermal performance and board space efficiency in high-frequency power converters.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - COMP | Error amplifier output / PWM comparator input | Interface for loop compensation network; sets stability and transient response. |
| 2 - FB | Inverting input of error amplifier | Connects to resistor divider for output voltage sensing; referenced to internal 2.514V bandgap. |
| 3 - CS | Current sense input | Accepts 0–1.0V signal with 100mV offset; triggers PWM shutdown on overcurrent. |
| 4 - RTCT | Oscillator timing control | Resistor-to-VREF + capacitor-to-GND sets frequency and max duty cycle via sawtooth generator. |
| 5 - GND | Power and signal reference ground | Must be low-impedance; separate high-di/dt return path required for stable operation. |
| 6 - OUT | MOSFET gate driver output | 1A peak sink/source capability; 20ns rise/fall into 1nF load enables fast switching. |
| 7 - VDD | Supply input | Operates from 7.5–14V; bypass with ceramic capacitor near pins for noise immunity. |
| 8 - VREF | 5.00V reference output | ±1.0%/–1.5% tolerance; powers external circuits and sets RTCT timing current. |
Key Features
| Feature | Design Value |
|---|---|
| 1A gate drive strength | Eliminates need for external driver stages in sub-100W converters. |
| 60µA start-up current | Reduces auxiliary winding size and losses in offline flyback designs. |
| 25ns CS-to-OUT delay | Enables <100ns overcurrent response time when combined with fast MOSFETs. |
| Trimmed RTCT discharge current | Ensures accurate deadtime and maximum duty cycle control across temperature. |
| Tight VREF tolerance (±1.0%/–1.5%) | Supports ±1% output voltage regulation without post-regulation trimming. |
| Pb-free RoHS-compliant packaging | Meets global environmental compliance requirements for industrial and telecom equipment. |
Applications
| Telecom Power Supply | Industrial DC-DC Converter |
|---|---|
Use Scenario: 48V input dual-output flyback supplying 1.8V and 3.3V rails in telecom shelf systems. IC Role / Device Role / Timing Role: Primary-side PWM controller regulating output via optocoupler feedback and peak current sensing. Use Value: 100% duty cycle and 2MHz capability allow compact transformer design and fast transient response to load steps. | Use Scenario: Isolated buck regulator powering PLC I/O modules from 24VDC industrial bus. IC Role / Device Role / Timing Role: Current-mode controller managing isolation barrier timing and providing inherent overcurrent protection. Use Value: 60µA start-up current reduces standby loss; 100mV CS offset enables precise low-current fault detection. |
| PC Power Supply | Wireless Base Station PSU |
Use Scenario: Secondary-side synchronous rectification control in ATX +12V rail using flyback topology. IC Role / Device Role / Timing Role: Adjustable-frequency PWM generator synchronizing gate drive with primary-side switching events. Use Value: 20ns rise/fall times minimize switching losses in high-efficiency 80 PLUS designs. | Use Scenario: Boost converter generating 28V bias rail from 12V battery backup in remote radio head units. IC Role / Device Role / Timing Role: High-frequency current-mode controller maintaining regulation during rapid input voltage transients. Use Value: Peak current mode control provides inherent cycle-by-cycle overcurrent limiting during antenna SWR faults. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PWM controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| UCC38C40DR | Lower max frequency (1MHz), higher start-up current (100µA), SOIC-8 only | Limited to ≤1MHz designs; less suitable for ultra-compact flyback transformers | Choose UCC38C40DR only if legacy SOIC footprint and lower cost outweigh frequency and efficiency needs. |
| ISL8840AAUZ | Same pinout, improved EMI performance, enhanced thermal rating (θJA = 140°C vs 165°C) | Better suited for convection-cooled enclosures with limited airflow | Select ISL8840AAUZ for new designs requiring extended lifetime in thermally constrained telecom deployments. |
Compared with UCC38C40DR and ISL8840AAUZ, ISL6840IU offers superior high-frequency capability (2MHz), lowest start-up current (60µA), and MSOP-8 packaging for space-constrained layouts-making it optimal for next-generation compact, high-efficiency power supplies.
Availability
ISL6840IU is available at Aetrix Electronics and suitable for telecom power supplies, industrial DC-DC converters, and wireless base station PSUs requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.
Supply support for ISL6840IU 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 microcontrollers, analog, power, and SoC solutions for automotive, industrial, infrastructure, and IoT applications.
The ISL6840IU belongs to Renesas' high-performance PWM controller product line, engineered specifically for efficient, reliable, and compact AC-DC and DC-DC power conversion in demanding industrial and communications systems.
FAQ
What is the UVLO threshold for ISL6840IU?
The ISL6840IU has a rising UVLO threshold of 7.0V and a falling threshold of 6.6V, providing 0.4V hysteresis. This ensures clean start-up from auxiliary supplies and prevents oscillation during brown-out conditions. The specification is guaranteed across –40°C to +105°C and applies specifically to the ISL6840IU variant within the ISL684x family.
Does ISL6840IU support 2MHz operation?
Yes, ISL6840IU supports adjustable switching frequencies up to 2MHz via the RTCT pin configuration. The oscillator uses a programmable sawtooth waveform; selecting appropriate RT (resistor to VREF) and CT (capacitor to GND) values enables stable operation across the full range. Performance curves in the datasheet confirm frequency stability versus temperature for ISL6840IU.
What package type is used for ISL6840IU?
The ISL6840IU is packaged in an 8-lead MSOP (Mini Small Outline Plastic) with outline drawing M8.118. It measures 3.0mm × 4.9mm × 1.1mm and features exposed pad thermal enhancement. This package is distinct from SOIC (M8.15) and DFN (L8.2x3) variants in the same family and is specified exclusively for ISL6840IUZ and ISL6840IUZ-T ordering options.
What is the maximum duty cycle supported by ISL6840IU?
The ISL6840IU supports a maximum duty cycle of 100%, as confirmed in the datasheet's part number table and electrical specifications. This distinguishes it from ISL6841IUZ (50%), ISL6844IBZ (50%), and other family members. The 100% capability enables high step-up ratio designs such as wide-input-range flyback and boost converters.
How does the CS pin offset affect current sensing in ISL6840IU?
The ISL6840IU features a nominal 100mV internal offset on the CS pin, meaning the effective current sense threshold begins at 100mV-not 0V. This offset improves noise immunity and defines the minimum resolvable current level. When designing the sense resistor, engineers must subtract this 100mV offset from the total CS voltage to determine actual sensed current, ensuring accurate overcurrent protection and regulation.
ISL6840IU Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- -
- Applications:
- Industrial Power Systems
- Voltage - Input:
- -
- Voltage - Supply:
- 7.5V ~ 14V
- Current - Supply:
- 5.5 mA
- Operating Temperature:
- -40°C ~ 105°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-MSOP
ISL6840IU FAQ
1.How can I place an order for ISL6840IU through Aetrix?
Please submit a Request for Quotation (RFQ) for ISL6840IU 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 ISL6840IU reliable?
The price and inventory of ISL6840IU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ISL6840IU is usually 5 days.
3.What payment methods are accepted for ISL6840IU?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ISL6840IU transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ISL6840IU?
ISL6840IU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ISL6840IU 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 ISL6840IU?
For technical support, including ISL6840IU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ISL6840IU requirements.
6.How does Aetrix verify that ISL6840IU is sourced from the original manufacturer or authorized distributors?
All ISL6840IU 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 ISL6840IU meets industry standards.
7.What is the process for return or replacement of ISL6840IU?
All ISL6840IU units undergo pre-shipment inspection (PSI). If there is an issue with ISL6840IU, 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 ISL6840IU part is unused and in its original packaging.
Return procedure for ISL6840IU:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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