Cirrus Logic CS1680 - Manual

Copyright  Cirrus Logic, Inc. 2014
(All Rights Reserved)
Cirrus Logic, Inc.
http://www.cirrus.com
CS1680
Dimmable LED Driver IC
for Low-voltage Lighting
Features
• Best-in-class Transformer Compatibility
- Magnetic Transformers
- Electronic Transformers
• Best-in-class Dimmer Compatibility
- Leading-edge (TRIAC) Dimmers
- Trailing-edge Dimmers
• High Efficiency
- Up to 80% for CS1680-00 Applications
- Up to 83% for CS1680-02 Applications
• Flicker-free Dimming
• 5% Minimum Dimming Level
• Cascade Boost-buck Topology with Constant-current
Output
- CS1680-00 Output Voltage 15V
- CS1680-02 Output Voltage 21V
• Fast Startup
• Tight LED Current Regulation: Better than ±10%
• >0.9 Power Factor on Magnetic Transformers
• Soft Start
• Protections:
- Output Open/Short
- Boost Overvoltage
- Overcurrent Detection
- External Overtemperature Using NTC
Overview
The CS1680 is a cascade boost-buck dimmable LED
driver for the 12V halogen lamp-replacement market.
The CS1680 uses a Cirrus Logic proprietary intelligent
digital control that provides exceptional single-lamp and
multi-lamp transformer compatibility for non-dimmer sys-
tems and dimmer systems paired with electronic and
magnetic low-voltage transformers.
The CS1680 integrates a continuous conduction mode
(CCM) boost converter that provides transformer com-
patibility and dimmer compatibility. An adaptive digital
algorithm controls the boost stage and dimmer compati-
bility operation mode to enable flicker-free operation
down to 5% output current with leading-edge and trail-
ing-edge dimmers.
Applications
• MR16 Lamps
• All 12VAC/VDC Low-voltage Lighting Applications
Ordering Information
See page 15 .
LED +
LED -
C
OUT
NTC
C B S T
D
B S T
Q
B UCK
CS1680
VAC
BUCKGD
BSTOUT
9
CLAMP
BUCKZCD
BUCKSENSE
eOTP
12
2
13
R CLA MP
R
S
C
NTC
R
B S T
D1
12VAC/VDC
D2
V
rect
V
BST
D B UCK
Q
CLA MP
C5 VDD
GPIO
BSTSENSE
BSTGD
C
rect
6
7
3
11
15
R
B UCK(S ense) R
B S T(S ense)
Q
B S T
R4
Z2
D3
D4
GND
1
CTRL1
16
R
CTRL1
R1
C4
R
CTRL2
CTRL2
4
5
14
Q1
Z1
R5
C1 C3
R3
U1
D5
D6
R
rect
C2
Q2
L
B S T
L
B UCK
R2
OCT’14
DS1055F1