Richtek RT9266GE, RT9266PE, RT9266PX5 Schematic [ru]
®
RT9266
Tiny Package, High Efficiency, Step-up DC/DC Converter
General Description
The RT9266 is a compact, high eff iciency, a nd low voltage
step-up DC/DC converter with a n Ada ptive Current Mode
PWM control loop, includes an error amplifier, ramp
generator, comparator , switch pa ss element and driver in
which providing a stable and high ef ficient operation over
a wide range of load currents. It operates in stable
waveforms without external compensation.
The low start-up input voltage below 1V makes RT9266
suitable for 1 to 4 battery cells applications of providing
up to 300mA output current. The 450kHz high switching
rate minimized the size of external components. Besides,
the 17μA low quiescent current together with high
efficiency maintains long battery lifetime.
The output voltage is set with two external resistors. Both
internal 2A switch and driver for driving external power
devices (NMOS or NPN) are provided.
Ordering Information
RT9266
Package Type
E : SOT-23-6
X5 : SOT-89-5
Features
zz
1.0V Low Start-up Input Voltage
z
zz
zz
z High Supply Capability to Deliver 3.3V 100mA with
zz
1 Alkaline Cell
μμ
zz
z 17
μA Quiescent (Switch-off) Supply Current
zz
μμ
zz
z Zero Shutdown Mode Supply Current
zz
zz
z 90% Efficiency
zz
zz
z 450kHz Fixed Switching Frequency
zz
zz
z Providing Flexibility for Using Internal and External
zz
Power Switches
zz
z Small SOT-23-6 & SOT-89-5 Package
zz
zz
z RoHS Compliant and 100% Lead (Pb)-Free
zz
Applications
z PDA
z DSC
z LCD Pa nel
z RF-Tags
z MP3
z Portable Instrument
z Wireless Equipment
Pin Configurations
Lead Plating System
(TOP VIEW)
P : Pb Free
G : Green (Halogen Free and Pb Free)
Note :
Richtek products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
FB
VDD LX
56
23
EN EXT
SOT-23-6
4
1
GND
EN VDD FB
SOT-89-5
LXGND
45
23
Marking Information
For marking information, contact our sales re presentative
directly or through a Richtek distributor located in your
area.
Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation.
DS9266-16 June 2013 www.richtek.com
©
1
RT9266
Typical Application Circuit
V
IN
Figure 1. RT9266 T ypical Application for Portable Instruments
3.1V to 5V for 12V
2.8V to 5V for 9V
V
IN
+
C4
100µF
+
C3
100µF
EN
RT9266
EXT GNDLXFB
RVDD
100
3.3 to 10 µH
VDD
L1
4.7µH
L1
C2
1µF
1N5819
D1
1N5819
D1
R1
1.6M/3M
R2
980k/1M
+
C1
100µF
V
OUT
3.3V/5V
EN
CVDD
1µF
RM
0.22
Q1
N MOS
C3
0.1µF
R1
860k/620k
R2
100k
VDD
RT9266
GNDLXFB
EXT
Figure 2. RT9266 High V oltage Applications
C2
1µF
+
C1
100uF
12V/9V
300mA
Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation.
©
DS9266-16 June 2013www.richtek.com
2
RT9266
V
3.3V/5V
L1
EN
+
C3
100µF
3.3 to 10 µH
VDD
RT9266
GNDLXFB
EXT
C2
1µF
V
IN
D1
1N5819
Q1
N MOS
R1
1.6M/3M
R2
980k/1M
+
C1
100µF
V
OUT
3.3V/5V
Figure 3. RT9266 for Higher Current Applications
LX
FB
L1
4.7µH
Q1
N MOS
C8
1µF
C7
1µF
C6
0.1µF
R1
620k
R2
100k
IN
C2
1µF
EXT
C1
1µF
EN
R3
100
VDD
RT9266
GND
C3
10µF
C4
10µF
C5
10µF
V
OUT2
+18V
10mA
V
OUT1
+9V
10mA
V
OUT3
-9V
10mA
Figure 4. RT9266 for Multi-Output Applications
Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation.
DS9266-16 June 2013 www.richtek.com
©
3
RT9266
Test Circuit
I (VIN)
V
IN
A
+
C3
100µF
A
I (VDD)
VDD
EN
RT9266
EXT GNDLXFB
Functional Pin Description
Pin No.
SOT-23-6 SOT-89-5
1 1 EN
2 -- EXT
3 5 GND
Pin Name
L1
10µH
C2
1µF
D1
1N5819
R1
1.6M/3M
R2
980k/1M
C4
102
+
C1
100µF
Pin Function
Chip Enable (Active High).
Output Pin for Driving External N-MOSFET .
Ground.
C5
106
V
OUT
3.3V/5V
4 4 LX Pin for Switching.
5 2 VDD
6 3 FB
Function Block Diagram
VDD
FB
EN
In put Posi tive Powe r Pin of RT9266 .
Feedback Input Pin.
Internal Reference Volt age for the Error Amplifier is 1.25V.
RT9266
Q1
N MOS
R1
1.25V
VDD
R2
Q2
N MOS
-
Loop Control Circuit
+
Over Temp.
Detector
Shut Down
EXT
LX
GND
Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation.
©
DS9266-16 June 2013www.richtek.com
4
RT9266
Absolute Maximum Ratings
z Supply V oltage------------------------------------------------------------------------------------------------------ −0.3V to 7V
z LX Pin Switch Voltage --------------------------------------------------------------------------------------------- −0.3V to 7V
z Other I/O Pin Voltages -------------------------------------------------------------------------------------------- −0.3V to (V
z LX Pin Switch Current --------------------------------------------------------------------------------------------- 2.5A
z EXT Pin Driver Current --------------------------------------------------------------------------------------------- 200mA
z Package Thermal Resista nce
SOT-23-6, θJC------------------------------------------------------------------------------------------------------- 145°C/W
SOT-89-5, θJC------------------------------------------------------------------------------------------------------- 45°C/W
z Operating Junction T emperature -------------------------------------------------------------------------------- 125°C
z Storage T emperature Range ------------------------------------------------------------------------------------- −65°C to +150°C
NOTE:
Absolute Maximum ratings are threshold limit values that must not be exceeded even for a n instant under a ny conditions.
Moreover, such values f or any two items must not be rea ched simulta neously . Operation above these absolute maximum
ratings may cause degradation or permanent da mage to the device. These are stress ratings only a nd do not necessarily
imply functional operation below these limits
+ 0.3V)
DD
Recommended Operating Conditions (1)
z Junction T emperature Range-------------------------------------------------------------------------------------- −40°C to 125°C
z Ambient T emperature Range-------------------------------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(VIN = 1.5V, VDD set to 3.3V, Load Current = 0, TA = 25° C, unless otherwise specified)
Parameter Symbol Test Conditions Min Typ Max Unit
Sta rt- UP Vo l t a g e
Operating VDD Range
Shutdown Current I (VIN) I
Switch-off Current I (VDD)
Continuous Switching Current
No Load Curre nt I (VIN) I
Feedback Reference V oltage
Switching Frequency
Maximum Duty
LX ON Resistance
Current Limit Setting
EXT ON Re sistance to VDD
EXT ON Re sistance to GND
V
I
ST
V
V
DD
EN Pin = 0V, VIN = 4.5V
OFF
I
SWITCH OFF
I
SWITCH
NO LOAD
V
F
D
I
LIMIT
VIN = EN = 3.3V, VFB = GND
VIN = 1.5V, V
REF
V
S
V
MAX
V
= 1mA
L
pin voltag e
DD
VIN = 6V
OUT
Clo se Loo p, V DD = 3.3V 1.22 5 1.2 5 1. 27 5 V
= 3.3 V
DD
= 3.3V
DD
V
= 3.3V
DD
= 3.3V
DD
V
= 3.3V
DD
V
= 3.3V
DD
= 3.3V
-- 0.98 1.05 V
2 -- 6 V
-- 0.01 1
-- 17 25
0.4 0.55 0.7 mA
--
75
(2)
--
425 500 575 kHz
85 95 -- %
-- 0.3 1.1
1.6 2
2.6
(3)
-- 5 8.5 Ω
-- 5 8.5
μA
μA
μA
Ω
A
Ω
Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation.
DS9266-16 June 2013 www.richtek.com
©
5
Loading...