1. General description
The GreenChip III+ is the third generation of green Switched Mode Power Supply (SMPS)
controller ICs. The SSL4101T combines a controller for Power Factor Correction (PFC)
and a flyback controller. Its high level of integration allows the design of a cost-effective
LED lighting application power supply with a very low number of external components.
The special built-in green functions provide high efficiency at all power levels. This applies
to quasi-resonant operation at high power levels, quasi-resonant operation with valley
skipping, as well as to reduced frequency operation at lower power levels. At low power
levels, the PFC switches off to maintain high efficiency.
During low power conditions, the flyback controller switches to frequency reduction mode
and limits the peak current to 25 % of its maximum value. This will ensure high efficiency
at low power and good standby power performance while minimizing audible noise from
the transformer.
The SSL4101T is a MultiChip Module, (MCM), containing two chips. The proprietary high
voltage BCD800 process which makes direct start-up possible from the rectified universal
mains voltage in an effective and green way. The second low voltage SiIlicon On Insulator
(SIO) is used for accurate, high speed protection functions and control.
The SSL4101T enables extremely efficient and reliable LED lighting application power
supplies with power requirements from 10 W to 300 W, to be designed easily and with a
minimum number of external components.
The new SSL4101T allows a typical 150 W LED lighting application power supply
(universal input, 48 V (DC) output, TEA1761T on the secondary side for Synchronous
Rectification) to achieve the following performances at full load:
• 120 V (AC): 92 % efficiency, 0.998 PF, 5.8 % THD, < 190 mW standby power
• 277 V (AC): 94 % efficiency, 0.978 PF, 9 % THD, < 350 mW standby power
1.1 Industry standard THD, low standby input power and high-efficiency
The SSL4101T enables LED lighting application power supplies to achieve the industry
standard of < 20 % THD for the input current at full load and all nominal input voltages:
100 V (AC), 120 V (AC), 230 V (AC), 240 V (AC) and 277 V (AC).
• Extremely low input power in Standby mode eliminates the need for an additional
housekeeping power supply to power the lighting controllers/dimmers.

• Using SSL4101T, a low power controller (< 50 mW) can be driven directly by the LED
lighting application power supply’s output while maintaining the input power in
Standby mode below the maximum of 0.5 W.
• Extremely high-efficiency can be achieved in LED lighting application power supplies
using the SSL4101T (between 92 % to 94 %). This enables the power supply to
operate reliably in enclosed spaces with very little cooling (which is typical for SSL
applications).2.1 Distinctive features
„ Integrated PFC and flyback controller.
„ True universal mains supply operation: 70 V (AC) to 305 V (AC).
„ High level of integration, resulting in a very low external component count and a
cost-effective design.
2.2 Green features
„ On-chip start-up current source.
2.3 PFC green features
„ Valley/zero voltage switching for minimum switching losses (NXP Semiconductors
patented).
„ Frequency limitation to reduce switching losses.
„ PFC is switched off when a low load is detected at the flyback output.
2.4 Flyback green features
„ Valley switching for minimum switching losses (NXP Semiconductors patented).
„ Frequency reduction with fixed minimum peak current at low power operation to
maintain high efficiency at low output power levels.
2.5 Protection features
„ Safe restart mode for system fault conditions.
„ Continuous mode protection by means of demagnetization detection for both
converters (NXP Semiconductors patented).
„ UnderVoltage Protection (UVP) (foldback during overload).
„ Accurate OverVoltage Protection (OVP) for both converters (adjustable for flyback
converter).
„ Open control loop protection for both converters. The open loop protection on the
flyback converter is safe restart.
„ IC OverTemperature Protection (OTP).
„ Low and adjustable OverCurrent Protection (OCP) trip level for both converters.
„ General purpose input for latched protection, e.g. to be used for system
OverTemperature Protection (OTP).

3. Applications
„ The device can be used in all LED lighting applications that require a very efficient, low
THD, high PF, true universal input voltage and cost-effective power supply solution
between 10 W and 300 W.