Cirrus Logic AN352 - Manual

Copyright  Cirrus Logic, Inc. 2011
(All Rights Reserved)
http://www.cirrus.com
Application Note
DRIVING MOSFETs WITH THE CS1501 & CS1601
1. Introduction
The CS1501 & CS1601 are high-performance digital power factor correction (PFC) controllers designed for switching mode pow-
er supply (SMPS) & lighting applications. This papers discusses the basics of driving power MOSFETs, including some guide-
lines for layout & component choices.
2. CS1501 & CS1601 Gate Drive
The CS1501 & CS1601 internal gate driver is a dual MOSFET between VDD & GND.
The CS1501 & CS1601 parameters for its internal gate drive are listed below.
1. C
L
is defined as the capacitive load that the IC drives. For test purposes, load capacitance (C
L
) is 1 nF and is
connected as shown in the following diagram.
Parameter Condition Symbol Min Typ Max Unit
PFC Gate Drive
Output Source Resistance I
GD
= 100 mA, V
DD
= 13 V R
OH
- 9 - Ω
Output Sink Resistance I
GD
= -200 mA, V
DD
= 13 V R
OL
- 6 -
Ω
Rise Time
1 C
L
= 1 nF, V
DD
= 13 V t
r
- 32 45 ns
Fall Time
1 C
L
= 1 nF, V
DD
= 13 V t
f
- 15 25 ns
Output Voltage Low State I
GD
= -200 mA, V
DD
= 13 V Vol - 0.9 1.3 V
Output Voltage High State I
GD
= 100 mA, V
DD
= 13 V Voh 11.3 11.8 - V
CS1501
CS1601
8 VDD
V
DD
7 GD
6 GND
GD OUT
GD
GND
CS
VDD
Buffer
S
1
R 1
R 2
R 3
TP
C
L
1nF
+15V
-15V
S
2
V
D D
AN352
MAR ‘11
AN352REV1