
Philips Electronics
GENERAL DESCRIPTION
The GreenChip(1)II is the second generation of green Switched Mode Power Supply (SMPS) control ICs operating directly from the rectified universal mains. A high level of integration leads to a cost effective power supply with a very low number of external components.
The special built-in green functions allow the efficiency to be optimum at all power levels. This holds for quasi-resonant operation at high power levels, as well as fixed frequency operation with valley switching at medium power levels. At low power (standby) levels, the system operates at a reduced frequency and with valley detection.
The proprietary high voltage BCD800 process makes direct start-up possible from the rectified mains voltage in an effective and green way. A second low voltage BICMOS IC is used for accurate, high-speed protection functions and control.
Highly efficient and reliable supplies can easily be designed using the GreenChipII control IC.
FEATURES
Distinctive features
• Universal mains supply operation (70 to 276 V AC)
• High level of integration, giving a very low external
component count.
Green features
• Valley or zero voltage switching for minimum switching
losses
• Efficient quasi-resonant operation at high power levels
• Frequency reduction at low power standby for improved
system efficiency (<3 W)
• Cycle skipping mode at very low loads; Pi <300 mW at
no-load operation for a typical adapter application
• On-chip start-up current source.
Protection features
• Safe restart mode for system fault conditions
• Continuous mode protection by means of
demagnetization detection (zero switch-on current)
• Accurate and adjustable overvoltage protection (latched
in TEA1533T, safe restart in TEA1533AT)
• Short winding protection
• Undervoltage protection (foldback during overload)
• Overtemperature protection (latched in TEA1533T, safe
restart in TEA1533AT)
• Low and adjustable overcurrent protection trip level
• Soft (re)start
• Mains voltage-dependent operation enabling level.
APPLICATIONS
Besides typical application areas, i.e. adapters and
chargers, the device can be used in TV and monitor
supplies and all applications that demand an efficient and
cost-effective solution up to 250 W.