Document
NEW PRODUCT
AL1677
UNIVERSAL, HIGH EFFICIENCY AND ACCURACY LED DRIVER CONVERTER
Description
The AL1677 is a universal AC-input (85~277 VAC), high-efficiency and high-accuracy Buck LED-driver converter. The AL1677 topology provides accurate constant current (CC) line and load regulation, operating at boundary conduction mode (BCM) to ease in EMI/EMC qualification and testing to meet the latest regulatory laws.
The AL1677 system removes the auxiliary winding and external highvoltage MOSFET with few external components to create a low bill of material (BOM) cost solution. The AL1677 has rich protection features to enhance system safety and reliability. With thermal foldback function, the AL1677 can reduce output current when the driver’s temperature is higher than the setting value.
Pin Assignments
(Top View)
GND 1 ROVP 2
NC 3 VCC 4
8 CS 7 CS 6D 5D
SO-8
The AL1677 is available in SO-8 package.
Features
> 90% Efficiency Valley Detection to Minimize Switching Loss Universal 85 to 277 VAC Input Range Internal MOSFET up to 500V Tight Current Sense Tolerance : ± 3% Low Startup Current: 170µA Low Operation Current: 100µA (Static) Standard Inductor (no auxiliary winding) Internal Protections
- Undervoltage Lockout (UVLO) - Leading-Edge Blanking (LEB) - Cycle-by-cycle Overcurrent Protection(OCP) - Output Open/Short Protection(OVP/OSP) - Open-Load and Reload Detection - Thermal Foldback Function(TFP) - Over-Temperature Protection(OTP) SO-8 Package Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. “Green” Device (Note 3)
Applications
Retrofit LED Lamps High Voltage DC-DC LED Driver General Purpose Constant Current Source
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. 2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free. 3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
AL1677
Document number: DS37526 Rev. 1 - 2
1 of 13 www.diodes.com
November 2015
© Diodes Incorporated
NEW PRODUCT
Typical Applications Circuit
AC Input
F1
DB1 C1
R1
D1
R4
+ C3
OUT
L1
R2
C2 R3
4 VCC D 5
3 NC
6
D
2 ROVP CS 7
1 GND CS 8
U1 AL1677
R5
Pin Descriptions
Pin Number 1 2 3 4 5,6 7,8
Pin Name GND ROVP NC VCC D CS
Ground Setting the Open Voltage of the Output No Connection Power Supply for the Device Internal High Voltage MOSFET’s Drain Current Sensing
Function
AL1677
Functional Block Diagram
VCC 4
STOP
Fault Management
OVP OSP OTP
OFF UVLO
VCC Management
VCC Clamp
VOVP_REF VREF
2 ROVP
NC 3
OVP OVP
TOFF
VOVP_REF
S R
Q
OSP
TOFF
Toff Detection (ZCD)
1 GND
STOP
Constant Current Control
Max Ton Limit
LEB
5,6 D
7,8 CS
AL1677
Document number: DS37526 Rev. 1 - 2
2 of 13 www.diodes.com
.