|
|
Boost Regulator. SP7648 Datasheet |
|
|
www.DataSheet4U.cSoomlved by
SP7648
TM
Low Reference High efficiency Boost Regulator
FeaTUReS
■ True Shutdown
■ 700mA Output Current at 3.3V Input; 4.2V
output
■ 92% Efficiency from 2.7V IN to 3.3VOUT
■ Wide Input Voltage Range: 2.7V to 4.5V
■ 5V Fixed or Adjustable Output
■ 0.3 1Switch
■ Integrated Synchronous Rectifier:0.3 1
■ Anti-Ringing Switch Technology
■ Programmable Inductor Peak Current
■ Logic Shutdown Control
■ Low 0.8V or 0.288V Reference Voltage
■ Small 10 pin DFN or MSOP Package
VBATT 1
FLASH 2
NC (Test) 3
RLIM 4
SHDN 5
10 VOUT
SP7648 9 LX
10 Pin DFN 8 PGND
7 GND
6 FB
Now Available in Lead Free Packaging
aPPLicaTiOnS
■ LED Driver
■ Camera Flash
■ Handheld Portable Devices
DeScRiPTiOn
The SP7648 is an ultra-low quiescent current, high efficiency step-up DC-DC converter ideal for
single cell Li-Ion or dual cell alkaline battery applications to drive various LEDs. The SP7648
combines low quiescent current and excellent light-load efficiency of PFM control. The SP7648
features synchronous rectification, a0.31charging switch, an anti-ringing inductor switch, under-
voltage lockout and programmable inductor peak current. The device can be shut down by a
1nA active LOW shutdown pin. A very low 0.288V reference voltage is optimized for driving a
constant current load.
Vin
(2.7 - 4.5V)
10µF
4.7µH
®
TYPicaL aPPLicaTiOn ciRcUiT
On/OFF
RLIM 1.0K1
VBATT SP7648 LX
SHDN
VOUT
RLIM
NC
FLASH
GND
PGND FB
470pF
10µF
0.331
D1
1K1
R2 R1
FLaSH
Q1
Mar16-06 Rev B
SP7648 Ultra-low Quiescent Current, High Efficiency Boost Regulator
© 2006 Sipex Corporation
|
|
LX, Vo, VBATT, FLASHOUT, FB to GND pin ...................... -0.3 to 6.0V
SHDN, FLASH ..................................................... -0.3V to VBATT+1.0V
Vo, GND, LX Current ....................................................................... 2A
Reverse VBATTCurrent .............................................................. 220mA
Forward VBATTCurrent .............................................................. 500mA
Storage Temperature .................................................. -65 °C to 150°C
aBSOLUTe MaXiMUM RaTingS
Operating Temperature ................................................ -40°C to +85°C
ESD Rating ........................................................................ 1.5kV HBM
These are stress ratings only and functional operation of the device at
these ratings or any other above those indicated in the operation sections
of the specifications below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may affect reliability.
eLecTRicaL SPeciFicaTiOnS
VBATT =VSHDN = 3.6V, VFB=ZeroV, ILOAD = 0mA, TAMB= -40°C to +85°C, VOUT = 5.0V, typical values at 27°C unless
otherwise noted. The z denotes the specifications which apply over full operating temperature range -40ºC to +85°C, unless
otherwise specified.
PaRaMeTeR
Min TYP MaX UniTS z
Input Voltage Operating Range, VBATT 2.7 - 4.5 V z
Output Voltage Range, VOUT
2.7 - 5.5 V z
Under Voltage Lock-out/UVLO
0.5 0.61 0.7 V z
Output Voltage, VO
Shutdown Current into VO, ISDO
Shutdown Current into VBATT, ISDB
4.6 5.0 5.4 V z
- 1 500 nA z
- 250 750 nA z
Efficiency
92 - % -
Inductor Peak Current Limit, IPK
650 800 1000 mA z
1600 mA z
Output Current (Note 2)
- 800 - mA -
- 400 - mA -
- 200 - mA -
Minimum Off-Time Constant KOFF
0.5 1.0 1.5 V*µs z
Maximum On-Time Constant KON
2.0 3.5 5.0 V*µs z
Enable Valid to Output Stable (Note 3) - 300 500 µs -
NMOS Switch Resistance
- 0.30 0.6 1 z
PMOS Switch Resistance
- 0.30 0.6 1 z
FB Set Voltage, VFB
0.76 0.8 0.84
0.266 0.288 0.310
V
V
z
z
FB Input Current
- 1 100 nA z
SHDN Input Voltage (Note 1)
VIL
VIH
SHDN Input Current
- - 0.5 V z
2.0 -
-
z
- 1 100 nA z
LX Pin Leakage
- - 3 µA -
FLASH Threshold V IL
VIH
- - 0.4 V
1.0 - - V
cOnDiTiOnS
After Startup
Internal Feedback Divider
VSHDN = ZeroV
VSHDN = ZeroV, VBATT = 2.7V
VBATT = 2.7V, IOUT = 200mA, RLIM = 2k1
RLIM = 2k1, IPK = 1600/RLIM
RLIM = 1k1, IPK = 1600/RLIM
VBATT = 2.7V, RLIM =1k1
VBATT = 2.7V, RLIM =2k1
VBATT = 2.7V, RLIM = 4k1
KOFF )T OFF (VOUT - VBATT)
KON *T ON (VBATT)
ILOAD = 1mA
INMOS = 100mA
IPMOS = 100mA
External feedback Flash = 0
External feedback Flash = 1
VFB =1.3V
VBATT = 2.7V
VBATT = 2.7V
note 1:SHDN must transition faster than 1V/100mS for proper operation.
{ } { }note 2:Output Current I =
VIN
VOUT
X Efficiency x
Inductor Peak Current - Inductor Ripple Current
2
note 3:Guaranteed by Design.
Mar16-06 Rev B
SP7648 Ultra-low Quiescent Current, High Efficiency Boost Regulator
© 2006 Sipex Corporation
|
Pin nUMBeR
1
Pin naMe
VBATT
2 FLASH
3 NC (Test)
4 RLIM
5 SHDN
6 FB
7 GND
8 PGND
9 LX
10 VOUT
Pin DeScRiPTiOn
DeScRiPTiOn
Battery Voltage. The startup circuitry is powered by this pin. Battery
Voltage is used to calculate switch off time: TOFF= K OFF/ (VOUT-
VBATT). When the battery voltage drops below 0.61V the SP7648
goes into an undervoltage lockout mode (UVLO), where the part is shut
down.
Reference Control Input. Internal Reference defaults to 0.8V if FLASH
= LOW and 0.288V if FLASH = HIGH.
No connection. This pin is bonded out for test purposes only and
must be left floating in all applications.
Current Limit Resistor. By connecting a resistor RLIM from this pin to
ground the inductor peak current is set by IPEAK=1600/RLIM. The range
for RLIM is 9k1(for 180mA) to 1.K 1(for 1.6A).
Shutdown Not. Tie this pin high to V BATT,for normal operation. Pull
this pin to ground to disable all circuitry inside the chip.
Feedback. Connect this pin to GND for fixed +5V operation. Connect
this pin to a resistor voltage divider between VOUTand GND for
adjustable output operation.
Ground. Connect to ground plane.
Power Ground. The inductor charging current flows out of this pin.
Inductor Switching Node. Connect one terminal of the inductor to the
positive terminal of the battery. Connect the second terminal of the
inductor to this pin. The inductor charging current flows into LX,
through the internal charging N-channel FET, and out the PGND pin.
Output Voltage. The inductor current flows out of this pin during
switch off-time. It is also used as the internal regulator voltage supply.
Connect this pin to the positive terminal of the output capacitor.
Note that the Thermal Pad (Pin 11) should be connected to Ground.
Mar16-06 Rev B
SP7648 Ultra-low Quiescent Current, High Efficiency Boost Regulator
© 2006 Sipex Corporation
|
| @ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site (Privacy Policy & Contact) |