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Description
The FP6795 is a step-up current mode PWM DC/DC
converter with an internal 2A, 0.16Ω N-channel
MOSFET. Pin selectable fixed switching frequency
(1.2MHz or 640KHz) and external compensation pin
provide the user flexibility in setting the loop dynamic, allowing the use of tiny, low profile inductors and
low value, low ESR ceramic output capacitors.
The FP6795 provides soft-start feature which is programmable with an external capacitor. In shutdown
mode, current consumption is reduced to only 0.1uA.
The FP6795 converts the input voltage ranged from
2.6V to 5.5V into an output voltage up to 16V.
FP6795 is available in the space-saving MSOP-8
package.
FP6795
Low-Noise Boost
DC-DC Converter
Features
● Operating Voltage from 2.6V to 5.5V
● Output Voltage from Input Voltage to 16V
● 90% Efficiency
● 2A, 0.16Ω Internal Power MOSFET
● Pin Selectable Switching Frequency (1.2MHz or
640KHz)
● Programmed Soft Start
● External Compensation Network
● 0.1uA Shutdown Current
● MSOP-8 Package
● RoHS Compliant
Applications
● LCD Displays
● Portable Applications
● Hand-Held Devices
● Digital Cameras
Pin Assignments
MS Package (MSOP-8)
MP Package (MSOP- 8<Exposed Pad>)
Fig
ure 1. Pin Assignment of FP6795 (Top View)
Ordering Information
FP6795□□□
TR: Tape / Reel
Blank: Tube
P: Pb Free with Commercial
tandard (RoHS Compliant)
Package Type
MS: MSOP-8
MP: MSOP-8 (Exposed pad)
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Typical Application Circuit
FP6795
Figure 2. Typical Application Circuit of FP6795
V
(V) V
IN
3.3 12.5 640 10 (TDK SLF7045) 33 (Ceramic) 120 1000 47 300
3.3 12.5 1200 6.8 (TDK SLF7045) 33 (Ceramic) 200 680 33 300
(V) fOSC (KHz) L (µH) C
OUT
(µF) R3 (kΩ) C4 (pF) C6 (pF) I
OUT
Functional Pin Description
Pin Name Pin Function
COMP Compensation Pin for Error Amplifier. Connect a series RC from COMP to ground.
FB Feedback Pin. The typical reference voltage is 1.24V. Set V
SHDN
GND Ground.
LX Switching Pin.
IN Power Input Pin.
FREQ
SS
Enable Pin. Connect SHDN low to turn off FP6795.
Frequency Select Pin. When FREQ connected to ground, the frequency is 640KHz. When FREQ connected to
, the frequency is 1.2MHz.
V
IN
Soft-Start Control Pin. Connect a capacitor (C3) to this pin. The pin will source 4uA constant current to charge the
capacitor. Leaving floating for not using soft-start.
= 1.24V (1+ R1/R2). See Figure 2.
OUT
(MAX) (mA)
OUT
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Block Diagram
SHDN
COMP
FB
1.24V
FREQ
Error Amplifier
_
+
OSCILLATOR
5µA
SHUTDOWN
Comparator
_
+
Clock
SLOPE
COMPENSATION
M
CURRENT
SENSE
Figure 3. Block Diagram of FP6795
CONTROL
and
DRIVE
LOGIC
UVLO
SOFT
START
FP6795
IN
4µA
SS
LX
GND
Absolute Maximum Ratings
● VIN to GND----------------------------------------------------------------------------------------------------- - 0.3V to + 6V
● LX to GND------------------------------------------------------------------------------------------------------ - 0.3V to + 18V
● SHDN, FB, SS, FREQ, COMP to GND------------------------------------------------------------------ - 0.3V to + 6V
● Power Dissipation:
MSOP-8 (P
MSOP-8<Exposed Pad> (P
) ----------------------------------------------------------------------------------------- 340mw (TA=70°C)
D
)-------------------------------------------------------------------------------- 500mw (TA=70°C)
D
● Package Thermal Resistance:
MSOP-8 (,θ
MSOP-8<Exposed Pad> (θ
)------------------------- --------------------------------------------------------------------------
JA
)------------------------------------------------------------------------------
JA
+160℃/W
+110℃/W
● Junction Temperature---------------------------------------------------------------------------------------- + 150°C
● Storage Temperature Range------------------------------------------------------------------------------- - 65°C to + 150°C
● Lead Temperature (Soldering, 10sec.) ------------------------------------------------------------------ 260°C
Note：Stresses beyond those listed under “Absolute Maximum Ratings" may cause permanent damage to the device.
Recommended Operating Conditions
● Supply Voltage, VIN------------------------------------------------------------------------------------------ 3.3V±10%, 5V±10%
● Output Voltage (Max.)--------------------------------------------------------------------------------------- 16V
● Operation Temperature Range---------------------------------------------------------------------------- - 40°C to + 85°C
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FP6795
Electrical Characteristics
(VIN=3V,
INPUT
Operation Voltage Range VIN 2.6 5.5 V
VIN Under Voltage Lockout UVLO
Quiescent Current IIN
Shutdown Current ISD
ERROR AMPLIFIER
Feedback Voltage VFB 1.227 1.24 1.253 V
FB Input Bias Current IFB V
Feedback Voltage Line Regulation 2.6V< VIN <5.5V 0.08 0.3 %/V
Transconductance gm ∆I =5µA 70 170 240 µS
Voltage Gain AV 700 V/V
OSCILLATOR
Frequency F
Maximum Duty Cycle T
N-CHANNEL SWITCH
Current Limit I
On-Resistance RON I
Leakage Current I
SOFT-START
Reset Switching Resistance 100 Ω
Charge Current ISS V
CONTROL INPUTS
Input High Level VIH
Input Low Level VIL
Hysteresis
Frequency Pulldown Current I
SHD N
PROTECTION
Thermal Shutdown TSD 160 °C
Thermal Shutdown Hysteresis
SHDN
=3V, FREQ=GND, TA=25°C, unless otherwise specified)
Parameter Symbol Test Conditions Min Typ Max Units
V
rising,
IN
typical hysteresis is 100mV
2.25 2.38 2.52 V
VFB=1.3V, not switching 160 350 µA
V
=1V, switching 0.8 5 mA
FB
SHD N
=0V 0.1 10 µA
=1.24V 0 150 nA
FB
FREQ=GND 540 640 740 KHz
FREQ=V
1000 1200 1500 KHz
IN
FREQ=GND 90 %
FREQ=V
LX
LX
SS
SHD N
SHD N
SHD N
90 %
IN
= 200mA 0.16 0.35 Ω
=16V 0.01 30 µA
=1.2V 1.5 4 7 µA
,FREQ 0.7*V
V
IN
,FREQ 0.3*V
,FREQ 0.1*VIN V
25 °C
Input Current I
OSC
DUTY
1.5 2 2.5 A
LIM
V
LXOFF
1.8 5 9 µA
FREQ
0.001 1 µA
HDN
TSD
∆
V
IN
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FP6795
Typical Performance Curves
2.00
1.75
1.50
1.25
1.00
0.75
1.2Mhz
640Khz
Switching Quiescent Current (mA)
0.50
2.5 3.0 3.5 4.0 4.5 5.0
Input Voltage (V)
Figure 4.Switching Quiescent Current vs. Input Voltage Figure 5. Maximum Output Current vs. Input Voltage
620
610
650
V
600
550
500
450
400
350
300
Maximum Output Current (mA)
250
200
=12.5V
OUT
L=6.8uH
FREQ=640Khz
2.5 3.0 3.5 4.0 4.5 5.0
Input Voltage (V)
1.250
1.245
600
590
Frequency (Khz)
580
570
560
-40 -20 0 20 40 60 80 100 120 140
Junction Temperature
o
C
VIN=3.3V
1.240
Reference Voltage (V)
1.235
1.230
-40 -20 0 20 40 60 80 100 120
Junction Temperature (oC)
Figure 6. Frequency vs. Junction Temperature Figure 7. Reference Voltage vs. Junction Temperature
95
90
Freq.=640Khz
85
80
75
70
Efficiency (% )
65
60
1 10 100 1000
Freq.=1.2Mhz
VIN=3.3V
V
Output Current (mA)
OUT
=12.5V
Output Voltage
Inductor Current
VIN=3.3V, V
C3=33nF,FREQ=640KHz, C
=12.5V, I
OUT
=10mA , L=10uH,
OUT
OUT
=33uF,
Figure 8. Efficiency vs. Output Current Figure 9.OCP Waveform
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Typical Performance Curves (Continued)
=3.3V, V
V
IN
200mA
10m
I
Load
Output
Inductor Current
=12.5V,FREQ=640KHz,C
OUT
OUT
=33uF
Figure 10. Load transient Response Figure 11. Load transient Response
V
IN
200mA
10mA
=3.3V, V
I
Load
Output
Inductor Current
=12.5V,FREQ=1.2MHz,C
OUT
FP6795
=33uF
OUT
VOUT
Inductor Current
V
=3.3V, V
IN
FREQ=640KHz, C
Figure 12. Start-up Waveform with Soft-start Figure 13. Start-up Waveform with Soft-start
=12.5V, I
OUT
OUT
=10mA , L=10uH, C3=33nF,
OUT
=33uF
SHDN
VOUT
Inductor Current
V
=3.3V, V
IN
FREQ=640KHz, C
OUT
=12.5V, I
OUT
=200mA , L=10uH,C3=33nF,
OUT
=33uF
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Typical Performance Curves (Continued)
VOUT
Inductor Current
VIN=3.3V, V
FREQ=640KHz, C
Figure 14. Start-up Waveform without Soft-start
=12.5V, I
OUT
OUT
=10mA , L=10uH, C3=33nF,
OUT
=33uF,
FP6795
Outline Information
MSOP- 8 Package (Unit: mm)
SYMBOLS UNIT
Note 1：Package Body Sizes Exclude Mold Flash and Gate
Note 2：Dimension L Is Measured in Gage Plane.
Note 3：Tolerance 0.10 mm Unless Otherwise Specified.
Note 4：Controlling Dimension Is Millimeter Converted Inch
Note 5：Design Following JEDEC MO-187.
DIMENSION IN MILLIMETER
MIN NOM MAX
A 0.81 1.02 1.12
A1 0.05 --- 0.15
A2 0.76 0.86 0.97
b 0.28 0.30 0.38
C 0.13 0.15 0.23
D 2.90 3.00 3.10
E 4.70 4.90 5.10
E1 2.90 3.00 3.10
e --- 0.65 ---
L 0.40 0.53 0.66
y --- --- 0.10
θ 0º --- 6º
Burrs.
Dimensions Are Not necessarily Exact.
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Outline Information (Continued)
MSOP- 8(Exposed Pad )Package (Unit: mm)
FP6795
Note 1：All Dimension Are In Millimeter
Note 2：Package Length Does Not Include
Note 3：Package Width Does Not Include
Mold Flash, Protrusions Or Gate Burr.
Interlead Flash Or Protrusions.
Life Support Policy
Fitipower’s products are not authorized for use as critical components in life support devices or other medical systems.
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