Owner manual

AN379
AN379REV2 3
2 Introduction
This application note is a guide to designing a low-voltage solid-state lighting (SSL) LED lamp circuit using Cirrus
Logic's CS1680. The first half of the design guide presents a step-by-step design procedure for calculating the re-
quired components for each stage of the system. The second half of the design guide uses a Cirrus Logic
CRD1680-7W reference design as an example to verify the design procedure. For in-depth implementation of the
CS1680, please consult documents in Further Reading on page 3 for IC and reference design details.
Further Reading
• Cirrus Logic, 2014. “Dimmable LED Driver IC for Low-voltage Lighting,” DS1055PP1, JAN 2014.
• Cirrus Logic, 2014. “CRD1680-7W 7Watt Reference Design,” DS1017RD3, JAN 2014.
NOTE
If any other Cirrus Logic document contains information conflicting with the device data sheet,
the device data sheet is considered to have the most current and correct data.
2.1 Definition of Acronyms
Acronym Description
PFC Power Factor Correction
CCM Continuous Conduction Mode
DCM Discontinuous Conduction Mode
ZCD Zero-current Detection
OVP Overvoltage Protection
eOTP External Overtemperature Protection
OCP Overcurrent Protection
iOTP Internal Overtemperature Protection
OLP Open Loop Protection
LED Light Emitting Diode
TXF Transformer
TRIAC
TRIode for Alternating Current, which is an electronic component that can conduct current
in either direction when it is triggered. It is formally called a bidirectional triode thyristor.
FET Field-effect Transistor
SSL
Solid-state lighting. Refers to a type of lighting that uses semiconductor LEDs as a source
of illumination rather than electrical filaments, plasma, or gas.
THD Total Harmonic Distortion
NTC Negative Temperature Coefficient thermistor