Isolated PWM Controllers
Renesas offers a broad portfolio of single-ended and double-ended isolated PWM controllers, and zero-voltage switching (ZVS) full bridge controllers.
Use the following table to identify which products will best meet the needs of your next isolated power project:
| Topology Characteristic | Flyback | Forward (Two Switch) | Active Clamp Forward | Push-Pull | Half-Bridge | Full-Bridge ZVS | Full Bridge (Telecom) Hard SW |
|---|---|---|---|---|---|---|---|
| Recommended Power Level | <150W | 120W~200W | 120- 400W | 100W~500W | 150W~500W | >400W | >400W |
| Efficiency | Least ~70-80% |
Moderate ~ 80-90% |
High 85~92% |
Moderate ~ 85-93% |
High ~ 95%+ |
High ~ 95%+ |
High ~ 95%+ |
| Recommended Devices | ISL884X ISL672X |
ISL672X | ISL6726 | ISL6741 | ISL674X | ISL675X | ISL674X |
| PFC Stage | ISL673X | ||||||
| Cost | Least | Low | Low | Low | Medium | High | High |
| Transfer Function = Vout/Vin | (Ns/Np)*D/(1-D) | (Ns/Np)*D | (Ns/Np)*D | 2*(Ns/Np)*D | (Ns/Np)*D | 2*(Ns/Np)*D | 2*(Ns/Np)*D |
| High Input Voltage | Good for bias supply | Good for 2-switch forward | Good | Not recommended | Good | Good | Good |
| Max. Duty Cycle | < 100% | < 50% (70% with active clamp) | 70% | < 50% each | < 50% each | < 50% each | < 50% each |
Family Values
- Full Family Features AC/DC Solution with Smallest Package
- Unique Output Current Sensing Scheme
- Unique Brick Wall OCP Protection Feature
- Unique Full Bridge ZVS Control Scheme
- Optimized/Adjustable Dead Time Control
Applications
- AC/DC Power Supply
- Brick Convertor
- Power Factor Correction (PFC) Board
- AC/DC Adapter
High Performance Industry Standard Single-Ended PWM Controllers
ISL884X Family
Renesas' family of flexible single-ended current mode pulse width modulating (PWM) controllers is designed for a wide range of DC/DC conversion applications including boost, flyback, and isolated output configurations. With fast signal propagation and output switching characteristics, these products are ideal for existing and new designs.
Features include 30V operation, low operating current, 90µA startup current, adjustable operating frequency to 2MHz, and high peak current drive capability with 20ns rise and fall times.
| Device Characteristic | ISL8840A | ISL8841A | ISL8842A | ISL8843A | ISL8844A | ISL8845A |
|---|---|---|---|---|---|---|
| UVLO | 7.0V | 7.0V | 14.4V | 8.4V | 14.4V | 8.4V |
| MAX Duty | 96% | 48% | 96% | 96% | 48% | 48% |
| Startup Current | 90µA | |||||
| VREF Accuracy | +1% – 1.5% | |||||
| Gate Drive | 1A | |||||
| Current Sense Prop Delay | 35ns | |||||
| Fsw Range | Up to 2MHz | |||||
| Error Amp BW | 1.5MHz | |||||
| Temp Range | -40 °C – 105 °C | |||||
| Minimum Duty | 0% | |||||
| Package | SOIC8 or MSOP8 | |||||
Family Values
- -55°C - 125°C Military Temperature Grade Available
- Small Package
- Best Reference Accuracy
- Least Current Sense Delay
- Wide BW Error Amp
Applications
- Telecom and Datacom Power
- Wireless Base Station Power
- File Server Power
- Industrial Power Systems
- PC Power Supplies
- Isolated Buck and Flyback Regulators
- Boost Regulators
Double-Ended PWM Controllers
ISL674X Family
Renesas' high performance double-ended pulse width modulating (PWM) controllers are suitable for both current- and voltage-mode control methods and designed for a wide range of power conversion applications using half-bridge, full bridge, and push-pull configurations.
| Device Characteristic | ISL6740 | ISL6740A | ISL6741 | ISL6742 | ISL6744A | ISL6745A |
|---|---|---|---|---|---|---|
| Control Mode | Voltage | Voltage | Peak current | Voltage or peak current | 50% free run | Voltage |
| Voltage Feed Forward | External | Internal | Not required | Adjustable | NA | External |
| Package | TSSOP16 | TSSOP16 | TSSOP16 | QSOP16 | MSOP8 | MSOP10 |
| FET Drive Voltage/Current | 5V/0.5A | 5V/0.5A | 5V/0.5A | VCC/10mA | VCC/1A | VCC/1A |
| SR Control | No | No | No | Yes | No | No |
| Output Current Sense | No | No | No | Yes | No | No |
| Current Limit Method | Hiccup with adjustable shutdown delay | Hiccup with adjustable shutdown delay | Pulse by pulse with optional hiccup | Pulse by pulse and/or average constant current limit | Pulse by pulse with delayed hiccup | Pulse by pulse with delayed hiccup |
| Internal Error Amplifier | No | No | No | Yes | No | No |
| UVLO | 7.25V | 7.25V | 7.25V | 8.75V | 6.3V | 6.3V |
| Frequency Sync Input | Yes | Yes | Yes | No | No | No |
| Fault Indicator | Yes | Yes | Yes | No | No | No |
Family Values
- Full Family to Support All Double-ended Topology
- Flexible Control Modes
- Reliable Protection Features
- Unique Output Current Sense Feature
- Optimized/Adjustable Dead Time Control
Applications
- AC/DC Power Supplies
- Bus Converters
- DC Transformers
- File Server Power
- Half-Bridge and Full-Bridge Converters
- Industrial Power Systems
- Line-regulated Bus Converters
- Telecom and Datacom Power
- Wireless Base Station Power
ZVS Full Bridge Controllers
ISL675X Family
The ISL675X family of controllers consists of high-performance, low-pin-count alternative zero-voltage switching (ZVS) full bridge pulse width modulating (PWM) controllers. These parts achieve ZVS operation by driving the upper bridge FETs at a fixed 50% duty cycle while the lower bridge FETS are trailing-edge modulated with adjustable resonant switching delays.
| Device Characteristic | ISL6752 | ISL6753 | ISL6754 | ISL6755 |
|---|---|---|---|---|
| SR Control | Yes | No | Yes | No |
| Output Current Sense | No | No | Yes | Yes |
| Soft Start | No | Yes | Yes | Yes |
| Package | QSOP16 | QSOP16 | QSOP20 | QSOP20 |
| Control Mode | Peak current | Peak current or voltage mode with FF | Peak current or voltage mode with FF | Peak current or voltage mode with FF |
| Internal Error Amp | No | Yes | Yes | Yes (2x) |
| Current Limit | Pulse by pulse | Pulse by pulse | Pulse by pulse and average current limit | Pulse by pulse and average current limit |
| Buffered OSC Output | Yes | Yes | Yes | Yes |
| Driver Voltage/Current | VCC/10mA | VCC/10mA | VCC/10mA | VCC/10mA |
| UVLO | 8.75V | 8.75V | 8.75V | 8.75V |
Family Values
- Unique PWM ZVS Control Algorithm
- Easy for True Peak Mode Control
- Easy for Diode Emulation and Light Load Burst Mode Operation
- Easy For SR Control
- Unique Output Current Sense Feature
- Simple Implementation for Brick Wall Constant Current Limit
- Simple Implementation for Current Sharing Control
Applications
- ZVS Full Bridge Converters
- Telecom and Datacom Power
- Wireless Base Station Power
- File Server Power
- Industrial Power Systems