Microchip HV9921DB1 Handleiding

Bekijk gratis de handleiding van Microchip HV9921DB1 (2 pagina’s), behorend tot de categorie Niet gecategoriseerd. Deze gids werd als nuttig beoordeeld door 27 mensen en kreeg gemiddeld 4.9 sterren uit 2 reviews. Heb je een vraag over Microchip HV9921DB1 of wil je andere gebruikers van dit product iets vragen? Stel een vraag

Supertex inc.

Supertex inc.

www.supertex.com

Doc.# DSDB-HV9921DB1

A032913

HV9921DB1

Introduction

The Supertex HV9921DB1 demoboard is a complete LED

power driver to supply a string of LEDs using the HV9921,

an integrated 3-pin high input voltage constant-current

buck regulator IC. The HV9921 integrates a 500V switching

MOSFET and can operate directly from the rectied universal

AC line voltage range of 80 to 265VAC.

The current in the LED string is internally programmed to

20mA ±15%. The HV9921DB1 is ideally suited for driving

strings of LEDs having forward voltage from 20 to 50V at

high efciency (typically 80% at 120VAC).

The HV9921DB1 is a peak current-controlled buck converter

operating with xed off-time of 10.5us. Its xed off-time

control scheme provides good stability and tight regulation of

the LED current throughout the input AC line voltage range.

As its switching frequency varies over the AC line cycle, the

HV9921 inherently introduces frequency dither and simplies

the compliance with EMI regulations.

Specications

Board Layout and Connection Diagram

Universal Off-line

LED Driver Demoboard

Connections

LED+: Connect the Anode of the LED string to this pin.

LED-: Connect the Cathode of the LED string to this pin.

AC1, AC2: Connect AC Line to these pins.

Note:

The demoboard is not protected from output open/

short circuit condition. Damage to the demoboard may

occur if the output load is not properly connected.

Parameter Value

Input voltage range80 to 265VAC

Load current20mA ± 15%

LED string voltage20 ~ 50V

Conducted EMICISPR15

Efciency 80% typ.

L1

C0

D1 U1

CDD

CIN

LED-

D2

+

D3

D5

D4

CIN2

LIN

C2

HV9921

LED+

LED String

VF = 20 to 50V

IF = 20mA

AC Line

80 - 265VAC

Product specificaties