Cirrus Logic CS1601H User Manual
Features, Applications, Overview
Copyright
Cirrus Logic, Inc. 2012
(All Rights Reserved)
Cirrus Logic, Inc.
CS1601
CS1601H
Digital PFC Controller for Electronic Ballasts
Features
Low PFC System Cost
Best-in-class THD
Digital EMI Noise Shaping Reduces Conducted EMI
Adaptive Switching Frequency Control Minimizes Boost
Inductor Size
High Efficiency Due to Zero-current Switching
Integrated Feedback Compensation Simplifies System
Design
Comprehensive Safety Features
• Undervoltage Lockout (UVLO)
• Output Overvoltage Protection
• Cycle-by-cycle Current Limiting
• Input Voltage Brownout Protection
• Open/Short Loop Protection for IAC & IFB Pins
• Thermal Shutdown
Pin Placement Similar to Traditional Boundary Mode (CRM)
Controllers
Applications
LED Power Supply/Driver
Fluorescent Ballasts
HID Ballasts
Overview
The CS1601 and CS1601H are digital power factor correction
(PFC) controllers designed to deliver the lowest PFC system
cost in electronic ballast applications. The controller operates
in a variable frequency discontinuous conduction mode (VF-
DCM) with zero-current switching optimized to deliver best-in-
class THD and minimize the size and cost of magnetic
components. The CS1601 operates at switching frequencies of
up to 70kHz, and the CS1601H operates at frequencies of up
to 100kHz.
The VF-DCM control algorithm varies both duty cycle and
frequency. This spreads the EMI frequency spectrum, thus
reducing conducted EMI filtering requirements. In addition, the
maximum switching frequency is reached at the peak of the AC
input, which allows the use of a smaller, more cost-effective
boost inductor.
The feedback loop is closed through an integrated
compensation network within the controller, eliminating the
need for additional external components. Protection features
such as overvoltage, overcurrent, open and short-circuit
protection, overtemperature, and brownout protect the system
during abnormal transient conditions.
Ordering Information
R1
R2
R3
R4
R7
R5
R6
8
1
D1
C1
C2
Regulated
DC Output
Q1
AC
Mains
BR 1
BR1
BR 1
BR1
CS1601
CS1601H
GD
ZCD
IFB
GND
CS
IAC
VDD
L
B
6
3
5
7
4
V
DD
STBY
2
V
rect
V
link
FEB’12
DS931F3
Document Outline
- Features
- Applications
- 1. Introduction
- 2. Pin Description
- 3. Characteristics and Specifications
- 4. Typical Electrical Performance
- 5. General Description
- 5.1 PFC Operation
- 5.2 Startup vs. Normal Operation Mode
- 5.3 Burst Mode
- 5.4 Output Power and PFC Boost Inductor
- 5.5 PFC Output Capacitor
- 5.6 Output IFB Sense and Input IAC Sense
- 5.7 Valley Switching
- 5.8 Brownout Protection
- 5.9 Overvoltage Protection
- 5.10 Overcurrent Protection
- 5.11 Overpower Protection
- 5.12 Open / Short Loop Protection
- 5.13 Internal Overtemperature Protection
- 5.14 Standby (STBY) Function
- 5.15 Summary of Equations
- 6. Package Drawing
- 7. Ordering Information
- 8. Environmental, Manufacturing, & Handling Information
- 9. Revision History