L6599ADTR STMicroelectronics, L6599ADTR Datasheet - Page 17

• Manufacturer Part Number: L6599ADTR
• Description: IC RESONANT CONVRTR CTRLR 16SOIC
• Manufacturer: STMicroelectronics

Specifications of L6599ADTR

• Applications: Resonant Converter Controller
• Voltage - Supply: 8.85 V ~ 16 V
• Current - Supply: 3.5mA
• Operating Temperature: 0°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 16
• Operating Supply Voltage: 8.15 V, 10.7 V, 17 V
• Maximum Operating Temperature: + 150 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• For Use With: 497-10542 - BOARD EVAL BASED ON L6599497-8429 - BOARD ADAPTER L6599/STP12NM50N497-5496 - EVAL BOARD FOR L6599
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Input: -
• Lead Free Status / Rohs Status: Compliant
• Other names: 497-8519-2

L6599A
7
Application information
The L6599A is an advanced double-ended controller specific for resonant half-bridge
topology (see
leg are alternately switched on and off (180° out-of-phase) for exactly the same time. This is
commonly referred to as operation at “50% duty cycle”, although the real duty cycle, that is
the ratio of the on-time of either switch to the switching period, is actually less than 50%.
The reason is that there is an internally fixed dead-time T
either MOSFET and the turn-on of the other one, where both MOSFETs are off. This dead-
time is essential in order for the converter to work correctly: it will ensure soft-switching and
enable high-frequency operation with high efficiency and low EMI emissions.
To perform converter's output voltage regulation the device is able to operate in different
modes
1.
2.
Figure 20. Multi-mode operation of the L6599A
Variable frequency at heavy and medium/light load. A relaxation oscillator (see
Section 7.1: Oscillator
which MOSFETs' switching is locked to. The frequency of this waveform is related to a
current that will be modulated by the feedback circuitry. As a result, the tank circuit
driven by the half-bridge will be stimulated at a frequency dictated by the feedback loop
to keep the output voltage regulated, thus exploiting its frequency-dependent transfer
characteristics.
Burst-mode control with no or very light load. When the load falls below a value, the
converter will enter a controlled intermittent operation, where a series of a few
switching cycles at a nearly fixed frequency are spaced out by long idle periods where
both MOSFETs are in OFF-state. A further load decrease will be translated into longer
idle periods and then in a reduction of the average switching frequency. When the
converter is completely unloaded, the average switching frequency can go down even
to few hundred hertz, thus minimizing magnetizing current losses as well as all
frequency-related losses and making it easier to comply with energy saving
recommendations.
(Figure
Figure
20), depending on the load conditions:
21.). In these converters the switches (MOSFETs) of the half-bridge
for more details) generates a symmetrical triangular waveform,
Doc ID 15308 Rev 5
D
inserted between the turn-off of
Application information
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