ISL6721.pdf 데이터시트 (총 23 페이지) - 파일 다운로드 ISL6721 데이타시트 다운로드

No Preview Available !

DATASHEET
ISL6721
Flexible Single-Ended Current Mode PWM Controller
FN9110
Rev 9.00
May 20, 2016
The ISL6721 is a low power, single-ended Pulse Width
Modulating (PWM) current mode controller designed for a wide
range of DC/DC conversion applications including Boost,
Flyback and isolated output configurations. Peak current
mode control effectively handles power transients and
provides inherent overcurrent protection. Other features
include a low power mode where the supply current drops to
less than 200µA during overvoltage and overcurrent shutdown
faults.
This advanced BiCMOS design features low operating current,
adjustable operating frequency up to 1MHz, adjustable
soft-start, and a bidirectional SYNC signal that allows the
oscillator to be locked to an external clock for noise sensitive
applications.
Applications
• Telecom and datacom power
• Wireless base station power
• File server power
• Industrial power systems
• Isolated buck and Flyback regulators
• Boost regulators
Features
• 1A MOSFET gate driver
• 100µA start-up current
• Fast transient response with peak current mode control
• Adjustable switching frequency up to 1MHz
• Bidirectional synchronization
• Low power disable mode
• Delayed restart from OV and OC shutdown faults
• Adjustable slope compensation
• Adjustable soft-start
• Adjustable overcurrent shutdown threshold
• Adjustable UV and OV monitors
• Leading edge blanking
• Integrated thermal shutdown
• 1% tolerance voltage reference
• Pb-free available (RoHS compliant)
Related Literature
AN1384, “ISL6841EVAL3Z Evaluation Board for General
Purpose Industrial Applications”
AN1491, “ISL6721EVAL3Z: Resonant Reset Forward
Converters for Low Power”
ISL6721
(16 LD TSSOP)
(16 LD SOIC)
TOP VIEW
GATE 1
ISENSE 2
SYNC 3
SLOPE 4
UV 5
OV 6
RTCT 7
ISET 8
16 VC
15 PGND
14 VCC
13 VREF
12 LGND
11 SS
10 COMP
9 FB
FN9110 Rev 9.00
May 20, 2016
Page 1 of 23

No Preview Available !

ISL6721
Ordering Information
PART NUMBER
(Notes 1, 2, 3)
PART
MARKING
TEMP. RANGE
(°C)
PACKAGE
(RoHS Compliant)
PKG.
DWG. #
ISL6721ABZ
6721ABZ
-40 to +105
16 Ld SOIC (150 mil)
M16.15
ISL6721AV-T
(No longer available, recommended
replacement: ISL6721AVZ-T)
ISL67 21AV
-40 to +105
16 Ld TSSOP (4.4mm)
M16.173
ISL6721AVZ
ISL67 21AVZ
-40 to +105
16 Ld TSSOP (4.4mm)
M16.173
ISL6721EVAL3Z
Evaluation Board
NOTES:
1. Add “-T” suffix for 2.5k unit for Tape and Reel options. Please refer to TB347 for details on reel specifications.
2. These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials and 100% matte tin
plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil Pb-free
products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
3. For Moisture Sensitivity Level (MSL), please see device information page for ISL6721. For more information on MSL please see techbrief TB363.
TABLE 1. KEY DIFFERENCES BETWEEN FAMILY OF PARTS
PART NUMBER
ISL6721 ISL6721A
   UVLO  thresholds (start/stop) (V)
8.25/7.70 6.80/6.20
   UV threshold   (V)
1.45
1.93
FN9110 Rev 9.00
May 20, 2016
Page 2 of 23

No Preview Available !

ISL6721
Functional Block Diagram
VCC
LGND
ISET
START/STOP
UV COMPARATOR
VREF
5V
1%
+ ENABLE
-
BG +-
THERMAL
PROTECTION
RESTART
DELAY
0.8
SS CHARGE
VOLTAGE CLAMP
SS CHARGED
SOFT-START
CHARGE 70µA
CURRENT
ON
OVERCURRENT
SHUTDOWN
DELAY
25µA
+
-
4.375V
ON
ISENSE
5k
SLOPE
VREF
+
S
53µA + 100mV
0.1
COMP
SS SS CLAMP
+
-
VFB
2.5V
ERROR
AMPLIFIER
+
-
- OC DETECT
+
OVERCURRENT
COMPARATOR
Q
Q
50µs
RETRIGGERABLE
ONE SHOT
SQ
RQ
OC LATCH
SS LOW -
+
SS LOW 270mV
FAULT COMPARATOR
LATCH
SQ
PWM
COMPARATOR
+-
1/3 100ns START
BLANKING
RQ
SET DOMINANT
VREF
UV COMPARATOR
4.65V -
+
BG
VREF
VREF
SS
15µA
VREF
20k
30k
RTCT
VREF
3.0V
1.5V
12k
ON
OSCILLATOR
COMPARATOR
-
+
1mA
ON
+
4V -
-
2V +
BI-DIRECTIONAL
SYNCHRONIZATION
OSC IN
CLK OUT
NO EXT SYNC
EXT SYNC BLANKING
SYNC IN SYNC OUT
VREF
SQ
RQ
BLANKING
COMPARATOR
3.0V
-
+
+
-
2.50V
-
+
1.45V
36k
OV
UV
VC
GATE
PGND
SYNC
100k
4.5k
FIGURE 1. FUNCTIONAL BLOCK DIAGRAM
FN9110 Rev 9.00
May 20, 2016
Page 3 of 23

No Preview Available !

ISL6721
Typical Application - 48V Input Dual Output Flyback, 3.3V at 2.5A,
1.8V at 1.0A
SP1 SP2
VIN+ P9
36-75V
C1
VIN-
R1
R2
SYNC
R5
R6
Q3
VR1
R24
C2
C18
CR6
C3 TP1
Q1
T1
ISOLATION
XFMR
CR5
R21
C21 + C15
CR2
C5
CR4
C19 +
C17
C22
+
C20
+3.3V
+ C16
+1.8V
RETURN
R16 R17 R18
C6 R19
U2
C14
R4 R3
R23
R25
Q2 C4
D1
TP3
TP5
D2
R22
TP2
U4
GATE
VC
ISENSE PGND
SYNC
VC
SLOPE VREF
UV LGND
OV SS
RTCT COMP
ISET
VFB
ISL6721
R26
R8
R10
C7 C8
R7 R9
R12
R11
R15
U3
R27
C9
R13
C10
C13
R20
R14
TP4
C12
C11
FIGURE 2. TYPICAL APPLICATION - 48V INPUT DUAL OUTPUT FLYBACK, 3.3V AT 2.5A, 1.8V AT 1.0A
FN9110 Rev 9.00
May 20, 2016
Page 4 of 23

No Preview Available !

ISL6721
Typical Boost Converter Application Schematic
VIN+
L1
C1
VIN-
CR1
R12 C12
Q1
R4 R1 R2 R3
+
C2
C3
C11
+VOUT
RETURN
R8
R5
C9
VIN+
C4 U1
GATE
VC
ISENSE PGND
SYNC VCC
SLOPE VREF
UV LGND
OV SS
RTCT COMP
ISET VFB
R10 C10
R9
R11
C8
R7
R6
C7 C6 C5
FIGURE 3. TYPICAL BOOST CONVERTER APPLICATION SCHEMATIC
FN9110 Rev 9.00
May 20, 2016
Page 5 of 23