Overview
The FAN6204AMX is a secondary-side synchronous rectification (SR) controller developed by onsemi. This IC is designed to enhance efficiency in power conversion systems by driving SR MOSFETs. It is suitable for use in flyback converters and forward free-wheeling rectification, supporting both continuous and discontinuous conduction modes (CCM and DCM) as well as quasi-resonant (QR) flyback converters. The FAN6204AMX utilizes a proprietary linear-predict timing-control technique, which simplifies the control method and improves noise immunity without the need for current-sense circuitry. It also features PWM frequency tracking and secondary-side winding voltage detection, enabling operation in both fixed and variable frequency systems.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VDD DC Supply Voltage | - | - | 30 | V |
| VDD-ON Turn-On Threshold Voltage | 4.3 | 4.8 | 5.3 | V |
| VDD-OFF Turn-Off Threshold Voltage | 4.0 | 4.5 | 5.0 | V |
| VDD-OVP VDD Over-Voltage Protection | 26.0 | 27.5 | 28.5 | V |
| IDD-OP Operating Current | - | 7.5 | 8 | mA |
| IDD-GREEN Operating Current in Green Mode | 1.1 | 1.2 | 1.3 | mA |
| TJ Junction Temperature | -40 | - | 150 | °C |
| TSTG Storage Temperature Range | -55 | - | 150 | °C |
| Package | - | - | 8-Pin SOP (Pb-Free) | - |
Key Features
- mWSaver Technology: Internal Green Mode to stop SR switching for lower no-load power consumption and ultra-low Green Mode operating current of 1.1 mA.
- Suitable for flyback converters in QR, DCM, and CCM operation, as well as forward free-wheeling rectification.
- PWM frequency tracking and secondary-side winding voltage detection for operation in both fixed and variable frequency systems.
- Ultra-low VDD operating voltage for various output voltage applications (5 V to 24 V).
- VDD pin over-voltage protection (OVP) to prevent damage from over-voltage conditions.
- 12 V (typical) gate driver clamp.
- Internal over-temperature protection to disable the SR gate at high temperatures.
- LPC and RES pin open/short protection to ensure safe operation.
Applications
- AC/DC notebook adapters.
- Open-frame SMPS (Switch-Mode Power Supplies).
- Battery chargers.
Q & A
- What is the primary function of the FAN6204AMX?
The FAN6204AMX is a secondary-side synchronous rectification (SR) controller designed to drive SR MOSFETs in flyback converters and forward free-wheeling rectification.
- What are the operating temperature ranges for the FAN6204AMX?
The operating temperature range is -40°C to +105°C, and the storage temperature range is -55°C to +150°C.
- What is the mWSaver Technology in the FAN6204AMX?
mWSaver Technology includes an internal Green Mode that stops SR switching to reduce no-load power consumption and operates with an ultra-low current of 1.1 mA in Green Mode.
- What types of protection does the FAN6204AMX offer?
The FAN6204AMX offers VDD over-voltage protection, internal over-temperature protection, and LPC and RES pin open/short protection.
- What is the typical gate driver clamp voltage?
The typical gate driver clamp voltage is 12 V.
- What are the common applications of the FAN6204AMX?
Common applications include AC/DC notebook adapters, open-frame SMPS, and battery chargers.
- What is the package type of the FAN6204AMX?
The FAN6204AMX comes in an 8-Pin Small Outline Package (SOP) that is Pb-Free.
- How does the FAN6204AMX handle over-temperature conditions?
The FAN6204AMX has internal over-temperature protection that disables the SR gate when the temperature exceeds 140°C and re-enables it when the temperature drops below 120°C.
- What is the purpose of the RES pin in the FAN6204AMX?
The RES pin is used to detect the output voltage level through a voltage divider and to control the linear predict timing.
- How does the FAN6204AMX reduce power consumption in light-load conditions?
In light-load conditions, the FAN6204AMX enters Green Mode, where the SR MOSFET stops switching, and the major internal blocks are shut down to reduce operating current to 1.1 mA.
