Analog Devices Inc. ADP1071 Isolated Flyback Controllers
Analog Devices Inc. ADP1071 Isolated Synchronous Flyback Controllers with integrated iCouplers® are Pulse-Width Modulation (PWM) current mode fixed frequency controllers designed for isolated dc-to-dc power supplies. These controllers come in ADP1071-1 and ADP1071-2 variants. The proprietary iCouplers® are integrated into the ADP1071-1/ADP1071-2 to eliminate the bulky signal transformers and optocouplers that transmit signals over the isolation boundary. This integration improves overall system reliability and reduces system design complexity, cost, and component count.
The isolated flyback controllers output regulation is achieved by sensing the output voltage on the secondary side. Whereas the feedback and the PWM signals are transmitted between the primary and secondary sides through the iCouplers. These ADP1071-1/ADP1071-2 controllers feature input current protection, OVP, UVLO, precision enable with adjustable hysteresis, OTP, and power-saving Light Load Mode (LLM). The isolated flyback controllers are available in a 16-lead SOIC_W package with an isolation voltage rating of 5kVrms and 24 terminal LGA package.
The ADP1071-1 targets high input voltage applications in which the dc input voltage can exceed 60V.
The ADP1071-2 is designed for isolated dc-to-dc applications typically with input voltage less than 36V.
Features
- Current mode controller for flyback topology
- ADP1071-1: programmable LLM or CCM for high VIN applications
- ADP1071-2: forced CCM operation
- Programmable slope compensation
- Integrated 5kV isolation (wide-body SOIC package) or 3.0kV (LGA package) rated dielectric isolation voltage with Analog Devices, Inc., patented iCoupler technology
- Wide voltage supply range:
- Primary VDD: up to 60V (ADP1071-2 only)
- Secondary VDD2: up to 36V
- Integrated 1A primary-side MOSFET driver
- Integrated 1A secondary-side MOSFET drivers for synchronous rectification
- Integrated error amplifier and <1% accurate reference voltage
- 50kHz to 600kHz programmable frequency range
- Duty cycle clamp limit 85%
- Programmable soft start and soft start from a precharged load
- Protection features such as short circuit, output overvoltage, and overtemperature protection
- Power saving LLM using MODE pin (ADP1071-1only)
- Cycle by cycle input overcurrent protection
- Precision enable UVLO with hysteresis
- Frequency synchronization
Safety
- UL recognition:
- 5000Vrms for 1 minute per UL 1577 (for wide-body SOIC package)
- 3000Vrms for 1 minute per UL 1577 (for LGA package)
- CSA component acceptance Notice 5A
- Available in 16-lead SOIC_W package and 24 terminal LGA package
- VDE certificate of conformity:
- DIN V VDE V 0884-10 (VDE V 0884-10):2006-12
- VIORM = 849V peak (for wide-body SOIC package)
- VIORM = 565V peak (for LGA package) CQC certification per GB4943.1-2011
Applications
- Isolated dc-to-dc or ac-to-dc power conversion
- Telecom and industrial
- Small cell
- PoE powered device
- Enterprise switches and routers
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