SP7661
Wide Input Voltage Range
3A, 600kHz, Buck Regulator
TM
Power
Blox
SP7661
DFN PACKAGE
7mm x 4mm (Option 2)
FEATURES
■ꢀ 4.75Vꢀtoꢀ22VꢀInputꢀVoltageꢀRangeꢀusingꢀSingleꢀSupply
■ꢀ 3Vꢀtoꢀ22VꢀInputꢀVoltageꢀRangeꢀusingꢀDualꢀSupply
■ꢀ ±1%ꢀ0.8VꢀReference
26
25
24
23
22
21
P
P
P
1
2
3
LX
LX
LX
GND
BOTTOM VIEW
GND
GND
■ꢀ 3AꢀOutputꢀCapability
Heatsink Pad 1
Connect to Lx
■ꢀ CurrentꢀLimitingꢀusingꢀInductorꢀDCR
■ꢀ BuiltꢀinꢀLowꢀRDS(ON) ꢀPowerꢀSwitches
■ꢀ 600kHzꢀFixedꢀFrequencyꢀOperation
■ꢀ OverꢀTemperatureꢀProtection
P
4
5
LX
CC
GND
Pin 27
GND
V
6
7
UV
V
FB
IN
COMP
SS
20
19
18
17
GND
GND
■ꢀ ShortꢀCircuitꢀProtectionꢀwithꢀAuto-Restart
■ꢀ WideꢀBWꢀAmpꢀAllowsꢀTypeꢀIIꢀorꢀIIIꢀCompensation
■ꢀ ProgrammableꢀSoftꢀStart
Heatsink Pad 2
Connect to GND
8
9
GND
ISN
V
IN
Pin 28
10
■ꢀ FastꢀTransientꢀResponse
BST
LX
■ꢀ HighꢀEfficiency:ꢀGreaterꢀthanꢀ93%ꢀPossible
■ꢀ NonsynchronousꢀStart-UpꢀintoꢀaꢀPre-ChargedꢀOutput
■ꢀ AvailableꢀinꢀRoHSꢀCompliant,ꢀLeadꢀFreeꢀPackaging:
Heatsink Pad 3
Connect to VINP
11
12
13
16
ISP
SWN
LX 15
14
Pin 29
LX
VINP
ꢀ
Smallꢀ7mmꢀxꢀ4mmꢀDFNꢀ
■ꢀ U.S.ꢀPatentꢀ#6,922,041
DESCRIPTION
TheꢀSP7661ꢀisꢀaꢀsynchronousꢀstep-downꢀswitchingꢀregulatorꢀꢀoptimizedꢀforꢀhighꢀefficiency.ꢀꢀTheꢀpartꢀisꢀdesignedꢀ
forꢀuseꢀwithꢀaꢀsingleꢀ4.75Vꢀtoꢀ22Vꢀsingleꢀsupplyꢀorꢀ3Vꢀtoꢀ22VꢀinputꢀifꢀanꢀexternalꢀVccꢀisꢀprovided.ꢀTheꢀSP7661ꢀ
providesꢀaꢀfullyꢀintegratedꢀbuckꢀregulatorꢀsolutionꢀusingꢀaꢀfixedꢀ600kHzꢀfrequency,ꢀPWMꢀvoltageꢀmodeꢀarchitecture.ꢀ
ProtectionꢀfeaturesꢀincludeꢀUVLO,ꢀthermalꢀshutdown,ꢀoutputꢀcurrentꢀlimitꢀandꢀshortꢀcircuitꢀprotection.ꢀTheꢀSP7661ꢀ
isꢀavailableꢀinꢀtheꢀspaceꢀsavingꢀDFNꢀpackage.
TYPICAL APPLICATION CIRCUIT
VIN 12V (9.6V-22V)
ꢀ
VOUT
ꢀ
3.30V, 0-3A
C2
Cꢀ
L1,ꢀWurthꢀ-744311220
2.2uH,ꢀ14ꢀmOhm,ꢀ7x7mm,ꢀ9A
22uF 22uF
LX
ꢀ
3
ꢀ
R3
5.11k
R4
5.11k
2
GND
C5
C4 47nF
ꢀ
2
26
25
24
23
22
2ꢀ
20
19
18
ꢀ7
ꢀ6
15
14
PGND
PGND
PGND
PGND
GND
VFB
LX
100uF
R9
ISP
61.9k
VFB
LX
LX
ISN
RZ3
ꢀ
RZ2
4.02k
56pF
3
CZ2
U1
400
4
Rꢀ
4
CVCC
ꢀ0k
SP7661
LX
6800pF
4.7uF
GND
5
VCC
UVIN
GND
GND
VIN
BST
LX
CZ3
1500pF
CPꢀ
6
NC
7
COMP
SS
VFB
CSS 47nF
R2
CF1
100pF
8
3.16k
9
GND
ISN
ꢀ0
ꢀꢀ
ꢀ2
ꢀ3
ISP
SD101AWS
DBST
C9 6.8nF
SWN
VIN
LX
22nF
LX
CBST
ISN
ISP
LX
LX
Rs2
Cs2
1ꢀOhm 2.2nF
Mar ꢀ-07 Rev N
SP766ꢀ Wide Input Voltage Range 3A, 600kHz Buck Regulator
© 2007 Sipex Corporation
ꢀ