HVLED805TR STMicroelectronics, HVLED805TR Datasheet - Page 3

• Manufacturer Part Number: HVLED805TR
• Description: IC LED DRVR ACDC OFFLINE 16NSOIC
• Manufacturer: STMicroelectronics
• Type: General Purposer

Specifications of HVLED805TR

• Constant Current: Yes
• Constant Voltage: Yes
• Topology: AC DC Offline Switcher, PWM
• Number Of Outputs: 1
• Internal Driver: Yes
• Type - Primary: General Purpose
• Voltage - Supply: 11.5 V ~ 23 V
• Mounting Type: Surface Mount
• Package / Case: *
• Internal Switch(s): Yes
• Efficiency: *
• Operating Supply Voltage: 11.5 V to 23 V
• Maximum Supply Current: 1.4 mA
• Maximum Power Dissipation: 0.9 W
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Frequency: -
• Operating Temperature: -
• Current - Output / Channel: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 497-10810-2

HVLED805
1
Description
The HVLED805 is a high-voltage primary switcher intended for operating directly from the
rectified mains with minimum external parts to provide an efficient, compact and cost
effective solution for LED driving. It combines a high-performance low-voltage PWM
controller chip and an 800V, avalanche-rugged power MOSFET, in the same package.
The PWM is a current-mode controller IC specifically designed for ZVS (zero voltage
switching) fly-back LED drivers, with constant output current (CC) regulation using primary-
sensing feedback. This eliminates the need for the opto-coupler, the secondary voltage
reference, as well as the current sense on the secondary side, still maintaining a good LED
current accuracy. Moreover it guarantees a safe operation when short circuit of one or more
LEDs occurs.
In addition, the device can also provide a constant output voltage regulation (CV): it makes
the application able to work safely when the LED string opens due to a failure.
Quasi-resonant operation is achieved by means of a transformer demagnetization sensing
input that triggers MOSFET’s turn-on. This input serves also as both output voltage monitor,
to perform CV regulation, and input voltage monitor, to achieve mains-independent CC
regulation (line voltage feed forward).
The maximum switching frequency is top-limited below 166 kHz, so that at medium-light
load a special function automatically lowers the operating frequency still maintaining the
operation as close to ZVS as possible. At very light load, the device enters a controlled
burst-mode operation that, along with the built-in high-voltage start-up circuit and the low
operating current of the device, helps minimize the residual input consumption.
Although an auxiliary winding is required in the transformer to correctly perform CV/CC
regulation, the chip is able to power itself directly from the rectified mains. This is useful
especially during CC regulation, where the fly-back voltage generated by the winding drops.
In addition to these functions that optimize power handling under different operating
conditions, the device offers protection features that considerably increase end-product’s
safety and reliability: auxiliary winding disconnection or brownout detection and shorted
secondary rectifier or transformer’s saturation detection. All of them are auto restart mode.
Doc ID 18077 Rev 1
Description
3/29