Richtek Wide Input Voltage Range DC/DC Power Solutions for ...

Application Note
Roland van Roy & Sophia Tong
AN034–July 2015
Richtek Wide Input Voltage Range DC/DC Power Solutions for Industrial,
Automotive and LED lighting applications
AN034
© 2015 Richtek Technology Corporation
1
Application Note
Table of Contents
Introduction ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------3
Power Conversion IC Portfolio Overview ----------------------------------------------------------------------------------------------------------------------------------------------4
1.4V~6V VIN, up to 4A, Buck converters/LDOs --------------------------------------------------------------------------------------------------------------------------------------5
4V~18V VIN, up to 6A Buck converters-------------------------------------------------------------------------------------------------------------------------------------------------6
3V~24V VIN, up to 8A Buck converters-------------------------------------------------------------------------------------------------------------------------------------------------7
3.5V~36V VIN, up to 0.6A Buck converters/ low quiescent LDOs --------------------------------------------------------------------------------------------------------------8
4.5V~36V VIN, up to 5A Buck converters ----------------------------------------------------------------------------------------------------------------------------------------------9
4.5V~80V VIN, up to 230mA. High voltage LDOs -----------------------------------------------------------------------------------------------------------------------------------10
4.5V~29V VIN, Boost controller -----------------------------------------------------------------------------------------------------------------------------------------------------------11
4.5V~50V VIN, Constant Current LED Driver Converters -------------------------------------------------------------------------------------------------------------------------12
4.5V~150V VIN, Constant Current LED Driver Controllers------------------------------------------------------------------------------------------------------------------------13
Power Switch and DDR termination regulator ---------------------------------------------------------------------------------------------------------------------------------------14
AN034
© 2015 Richtek Technology Corporation
2
Application Note
Introduction
Richtek provides comprehensive power conversion solutions for input voltages ranging from 1.4V up to 80V, suitable for a wide range of applications in the industrial, automotive,
and professional lighting field.
The selected product range in this brochure highlights Richtek linear and switching converters, from low quiescent LDOs to highly efficient step-up and step down converters and
controllers, LED lighting drivers, Power Switches and DDR terminators.

Many parts come with extra features such as PGOOD signaling and programmable Soft-Start.



Richtek Buck converters use robust control architectures like ACOT ™ which is compensation free and simple to use.
The listed parts have thermally enhanced packages, allowing higher ambient temperature operation.
Richtek also offers both 3T parts (qualified over the full -40C ~ 85C industrial temperature range) and Automotive AEC-Q100 qualified parts.

All parts can be used with ceramic input and output capacitors which extends operation life time.
These features make the Richtek parts extremely suitable for demanding applications fields such as:
Industrial
AN034



eMetering
Embedded Computing
Industrial control systems



Portable equipment
Instrumentation
Surveillance Cameras
Automotive


Infotainment
USB power
Communications



Networking
Servers
Data storage
© 2015 Richtek Technology Corporation
Professional LED Lighting



Car lighting
Street Lighting
Display lighting

Lighting controls
3
Application Note
Power conversion IC Portfolio for Industrial, Automotive and LED lighting applications
AN034
© 2015 Richtek Technology Corporation
4
Application Note
Step down converters and LDOs
1.4V~6V VIN, up to 4A, Buck converters/LDOs, Ideal for Li-ion battery powered applications, 5V input power rails and intermediate power conversions.
P/N
Description
RT2657BQ
IOUT
0.6A
RT5712A
2A
1.4V ~ 6V
LDOs/Buck
up to 4A
VIN
converters
IOUT
VIN
2.7V~5.5V
2.7V~5.5V
VOUT
0.6V~5.5V
0.6V~3.4V
fSW
Buck converter
3A
2.95V~6V
VREF: 0.827V
Package


AEC-Q100 Compliance
Built-in Soft-Start

1.5A Current limit peak
1MHz




RON 100mΩ HS / 70mΩ LS
1.2ms fixed Soft-Start
CMCOT topology: good transient response, stable with MLCC
Hiccup or Latch off UVP
WDFN-6L-2x2
300kHz~2MHz



RON 45mΩ HS / 45mΩ LS
Power Good
Adjustable Soft-Start
WQFN-16L-3x3


RON 50mΩ HS / 40mΩ LS
CMCOT topology: good transient response, stable with MLCC
2.25MHz
Synchronous
RT8079
Key Features
WDFN-8L 3x3
RT8086B
3.5A
2.8V~5.5V
0.6V~3.3V
1.2MHz



Power Good
Built-in Soft-Start
Hiccup UVP
UQFN-12L-2x2 (FC)
RT8074
4A
2.7V~5.5V
0.8V~5V
200kHz~2MHz

Built-in Soft-Start
PSOP-8
P/N
Description
IOUT
VIN
VOUT
VDropout
Key Features
Package
1A
2.2V~6V
1.2V~VIN
200mV@1A


AEC-Q100 Compliance
Low Quiescent 1.5µA in Shutdown Mode
PSOP-8
RT2517C
1A
2.2V~6V
1.2V~VIN
150mV@1A


3T Grade
Low Quiescent 0.1µA in Shutdown Mode
VDFN-8AL-3x3
RT2518
1A
1.4V~6V
0.5V~VIN
200mV@1A


3T Grade
EN control
WDFN-8L-3x3
2A
1.4V~6V
0.5V~VIN
400mV@2A


3T Grade
EN control
PSOP-8
RT2517B
LDO
LDO with EN
RT2515H
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© 2015 Richtek Technology Corporation
5
Application Note
4V~18V VIN, up to 6A Buck converters, ideal for applications powered from 5V~12V power rails, intermediate power conversions, etc.
P/N
RT8297B
Description
Current Mode
Synchronous Buck
converter
IOUT
1.5A
4V ~ 18V
Buck
1.5A ~ 6A
VIN
converters
IOUT
VIN
4V~17V
VOUT
0.8V~12V
fSW
800kHz
Key Features

Power Good
Package
WDFN-8L-2x2
RT6232/33/A/B
A:PSM
B:PWM
RT7275/76
75:PWM
76:PSM
RT7231/32
31:PWM
2A/3A
500kHz
3A
700kHz
WDFN-8L-2x3

ACOT™ topology for ultra-fast transient response and
MLCC COUT stable
Adjustable Soft-Start


Power Good
Force PWM or PSM (enhanced light load efficiency)

ACOT™ Synchronous
Buck converter
4.5V~18V
0.765V~8V
4A
650kHz
5.5A
650kHz
32:PSM
RT6206B
PSM
RT2859A/B
A:PSM
B:PWM
RT2855A/B
A:PSM
B:PWM
3A
ACOT™ Synchronous
650kHz
4.5V~18V
Buck converter
0.765V~7V
4A
650kHz
Current Mode
RT2856
AN034
Synchronous Buck
converter
6A
4.5V~18V
VREF: 0.8V
200kHz~1.6MHz
© 2015 Richtek Technology Corporation
WDFN-10L-3x3
PTSSOP-14
WDFN-10L-3x3
PTSSOP-14
WDFN-10L-3x3
PSOP-8


3T Grade
ACOT™ topology for ultra-fast transient response and
MLCC COUT stable
WDFN-16L-3x3



Adjustable Soft-Start
Power Good
Hiccup or Latch off UVP
WDFN-16L-3x3


3T Grade
RON 26mΩ HS / 19mΩ LS



Adjustable Soft-Start
Power Good
VREF:0.8V ±1% over -40C ~ 85C
WQFN-14AL-3.5x3.5
6
Application Note
3V~24V VIN, up to 8A Buck converters, ideal for applications powered from 12V system power rails requiring extra input voltage de-rating
P/N
RT7262/63/64
Description
Current Mode
Synchronous Buck
converter
RT8299
RT6220
RT7238
ACOT™
Synchronous
Buck converter
ACOT™
Synchronous
Buck converterwith
3.3V/5V LDO
IOUT
3V ~ 24V
Buck
up to 8A
VIN
converters
IOUT
VIN
VOUT
fSW
Key Features
2A/3A/4A
4.5V~21V
0.808V~15V
500kHz
 Synchronized external clock from 300kHz~2MHz
 Adjustable Soft-Start
 Low LS RON ideal for low VOUT
3A
3V~24V
0.8V~15V
500kHz
 Power Good and very wide VIN range
Package
WDFN-14L-4x3
PSOP-8
WDFN-10L-3x3
PSOP-8
 ACOT™ topology for ultra-fast transient response and
6A
4.5V~23V
0.6V~5V
500kHz
MLCC COUT stable
 RON 31mΩ HS / 20mΩ LS
UQFN-16L-3x3(FC)
 Power Good
8A
8V~23V
0.9V~5V Adj.
3.35V fixed
5.0V fixed
500kHz
 ACOT™ topology for ultra-fast transient response and
MLCC COUT stable
 RON 27mΩ HS / 10mΩ LS
UQFN-10L-3x3(FC)
 With fixed 70mA 3.3V/5V LDO
Also see:
Application note ‘’Buck converter selection criteria’’
Application note "Comparing Buck converter topologies–Current mode, CMCOT™ and ACOT™"
AN034
© 2015 Richtek Technology Corporation
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Application Note
3.5V~36V VIN, up to 0.6A Buck converters/ low quiescent LDOs, ideal for applications from 24V rails, for powering low power MCUs in e-metering, lighting
controls, sensors, etc.
P/N
RT6208
Description
Buck converter
RT6200
P/N
RT9058
RT2560Q
IOUT
LDOs/Buck
0.1A~0.6A
VIN
converters
IOUT
VIN
VOUT
0.1A
4.5V~36V
Adj.VOUT
VREF = 0.8V
0.6A
4.5V~36V
0.8V~15V± 2%
Description
LDO
3.5V ~ 36V
IOUT
100mA
VIN
fSW




Hysteretic mode operation
using Boundary conduction
mode
2.5V,3.3V,5V,12V fixed
Synchronous
Adjustable current limit
25µA IQ
Very high efficiency at low load
 Asynchronous with internal 0.3Ω HS MOSFET
1.2MHz
VOUT
3.5V~36V
Key Features
VDropout
Key Features
 AEC-Q100 Grade (RT2560Q)
550mV@10mA
 2µA ultra low IQ
Package
SOT-23-6
PSOP-8(w/PG)
SOT-23-8(w/PG)
SOT-23-6
Package
SOT-23-3
SOT-89
PSOP-8
Application note “How to power small MCU’s from industrial supply rails”
4.5V ~ 36V
VIN
5
CIN
(open = automatic start)
3
SW
VIN
RT6208GE
EN
FB
4 ISET
R1
(peak current setting)
6
VOUT
3.3V/100mA
L1
R2
C1
COUT
1
SW VIN ISET
R3
GND
2
6
5
4
2
3
FB GND EN
SOT-23-6
36V low power buck delivering high efficiency from light load to full load conditions.
AN034
© 2015 Richtek Technology Corporation
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Application Note
4.5V~36V VIN, up to 5A Buck converters, ideal for applications from 24V power rails, such as USB supply, displays, medium power MCUs, Instrumentation, etc.
4.5V ~ 36V
VIN
P/N
Description
RT7272A/B
3A
(PWM/PSM)
RT2872
RT2875A/B
(latch UV/hiccup UV)
IOUT
VOUT
4.5V~36V
3A
Current Mode
Buck converter
VIN
3A
4.5V~36V
RT8289
5A
5.5V~32V
RT8279
peak
5.5V~36V
RT2805A
5A
peak
fSW
0.8V~30V
4.5V~36V
Key Features
 Adjustable current limit: 2.5A~5.5A
500kHz
 Integrated 150/80mΩ HS/LS MOSFET
Package
PSOP-8
300kHz~1MHz
 AEC-Q100 Grade 3
 105/80mΩ HS/LS MOSFET
 Ext.compensation
PSOP-8
0.6V~24V
300kHz~2.1MHz




PTSSOP-14
1.222V~26V
500kHz
0.8V~30V
5.5V~36V
3A ~ 5A
IOUT
Buck
converters
1.222V~26V
VIN
4.5V ~ 36V
3
7
(frequency setting)
 3T Grade
 Asynchronous with integrated 110mΩ HS MOSFET
 Internal compensation & Soft-Start
SW
R4
ROSC
 Internal compensation & Soft-Start
RT2872GSP
2
VIN
BOOT
CIN
EN
 Asynchronous with integrated 100mΩ HS MOSFET
500kHz
8
EN
RT
3T Grade
95/70mΩ HS/LS MOSFET
Ext.compensation
Adjustable current limit:1.5A~6A
GND
4, 9 (pad)
PSOP-8
C11
VOUT
(3A max)
L1
1
R1
FB 5
COMP
PSOP-8
6
COUT
R2
C7
R3
36V / 3A buck converter for automotive applications.
AN034
© 2015 Richtek Technology Corporation
9
Application Note
4.5V~80V VIN, up to 230mA. High voltage LDOs, ideal for applications from highly fluctuating power rails (±60/±80V) such as automotive battery powered
applications, for powering sensors, low power MCUs, etc.
4.5V ~ 80V
LDOs
VIN
P/N
Description
IOUT
20mA ~ 230mA
VIN
VOUT
IOUT
VDropout
Key Features
Package
RT2571
50mA
4.5V~60V
2.5V,3.3V,5V Fixed
1.25-60V Adj.
250mV@50mA
 30µA low IQ
 -60V reverse protection
PSOP-8, PMSOP-8, SOT-223
RT9074
100mA
4.5V~60V
2.5V,3.3V,5V Fixed
1.25-60V Adj.
300mV@100mA
 30µA low IQ
 -60V reverse protection
PSOP-8, PMSOP-8, SOT-223
RT9068
230mA
4.5V~60V
2.5V,3.3V,5V fixed
1.25V~60V Adj.
230mV@50mA
 30µA low IQ
 -60V reverse protection
PSOP-8, PMSOP-8, SOT-223
RT9072A/B
20mA
4.5V~80V
1.25V~60V Adj.
180mV@20mA
LDO
VIN
4.5V ~ 60V
CIN
180nF
Shut Down
RT9068-xx
VIN
VOUT
VOUT
2.5V/3.3V/5V
VIN
4.5V ~ 60V
CIN
180nF
COUT
1μF
SENSE
SHDN
VOUT
SENSE
NC
NC
GND
GND
8
2
3
7
GND
9
4
6
5
VIN
GND
GND
SHDN
Shut Down
 23µA low IQ
SOT-23-5, WDFN-8L 3x3
 -80V reverse protection
RT9068
VIN
VOUT
SENSE
SHDN
VOUT
1.25V ~ 60V
CCOMP
R1
COUT
1μF
FB
GND
PMSOP-8
R2
VOUT
SENSE
FB
NC
8
2
3
4
GND
7
9 6
5
VIN
GND
GND
SHDN
PMSOP-8
1
VIN
2
3
GND VOUT
(TAB)
SOT-223
8
VOUT
SENSE
2
NC
NC
3
GND
GND
6
GND
5
SHDN
9
4
VIN
7
PSOP-8
RT9068 high voltage LDO in fixed and adjustable versions.
AN034
© 2015 Richtek Technology Corporation
VOUT
SENSE
2
FB
3
NC
4
GND
8
VIN
7
GND
6
GND
5
SHDN
9
PSOP-8
10
Application Note
Step up controller for high power Boost applications
4.5V~29V VIN, Boost controller, ideal for applications in high boost power, such as 24V to 48V conversion, large display backlighting, thermal printers, battery
pack charging, etc.
P/N
RT8525
Description
Boost controller
4.5V ~ 29V
Boost
IOUT
VIN
controller
limited by ext.
MOSFET
IOUT
VIN
Limited by ext.MOSFET
VOUT
4.5V~29V
Limited by MOSFET
VIN
4.5V ~ 29V
Key Features
 Programmable Soft-Start Time
 Programmable Boost SW Frequency
 Fault signaling pin
50K-600kHz
L1
Package
SOP-14
D1
VOUT
RIN
CIN
VIN
DRV
RT8525GS
CIN1
ISW
VDC
VREF
Rp1
R4
COUT
Q1
RSLP
RSW1
RSW2
CREF
PWMI
R14
RFB1
Rp2
FB
Fault
FAULT
EN
COMP
EN
CC2
fSW
RC1
CC1
Rt
CSS
RFB2
ROVP1
OOVP
FSW
SS
AGND PGND
ROVP2
VDC
VIN
COMP
SS
FSW
AGND
PWMI
14
2
13
3
12
4
11
5
10
6
9
7
8
DRV
PGND
EN
ISW
OOVP
FB
FAULT
SOP-14
RT8525 Boost controller application for high output powers
AN034
© 2015 Richtek Technology Corporation
11
Application Note
LED Drivers
4.5V~50V VIN, Constant Current Buck converters, ideal for medium power industrial LED lighting applications.
4.5V ~ 50V VIN
P/N
RT8471
RT8474/A
(A:OVP for hot
swap function)
AN034
Description
Hysteretic control, high
brightness LED driver
50V high voltage LED driver
IOUT
1/1.2A
2A
VIN
7V~36V
4.5V~50V
LED drivers
Key Features
 Simple application: no COUT needed
 Analog or digital dimming control
 Ultra-fast response
 Colour control for single string
 Analog or digital dimming control
 Low RON
© 2015 Richtek Technology Corporation
up to 2A
Where to use, (application examples)
 LED strips, signage, < 15W
 MR-16 ≤ 4WSingle string buck with color control via
LED shunt dimming
 LED strips, signage, LED engines, POUT< 30W
 RT8474A with special open string protection is ideal
Package
TSOT-23-5
PMSOP-8
PSOP-8
PSOP-8
for hot-swap LED string
12
Application Note
4.5V~150V VIN, Constant Current Buck / Boost / Buck-Boost controllers, ideal for industrial/automotive LED lighting applications, such as high power LED string
applications, street lighting, display backlight.
P/N
Description
IOUT
RT8477A
Buck / Boost controller
RT8475/
RT8494
LED Driver Controller for Buck,
Boost or Buck-Boost Topology
RT8485
LED Driver controller for
Buck/Boost/Buck-Boost topologies
VIN
Limited by
external
MOSFET
ext. MOSFET
limited
LED drivers
4.5V ~ 150V VIN
VLED
Key Features
Where to use
Package
4.5V~50V
up to 50V
 low component count
 Analog or PWM Dimming control
 Wide input / output range with medium
power: LED modules, down-light,
emergency lighting
 Buck ≤ 60W, Boost ≤ 40W
4.5V~36V
(IC VIN)
up to 90V
 Programmable FSW 100kHzto 1MHz
 Analog or Digital to Analog Dimming control
 Industrial Display Backlight
 AEC-Q100 Compliance (RT8494)
SOP-14,
WQFN-16L 3x3
up to 150V
 Programmable switching frequency
 Analog, Digital or Digital to Analog Dimming
control
 Street lighting
 High power, high LED string application
 Buck ≤ 100W, Boost ≤ 80W
SOP-14
4.5V~36V
(IC VIN)
PSOP-8
VIN2
Up to 150V
ISP 3
CIN2
VIN
4.5V ~ 50V
CIN
VIN1
4.5V ~ 36V
ISP 2
R1
C1
ISN 3
Ext. Sync
RT8477AGSP
D1
5 CTL
Analog Dimming
4 VC
C5
COUT
Digital Dimming
L1
C2
R3
CIN1
R2
1 VCC
11 VCC
DRV
7
8 CREG
SENS 6
GND
C3
9 (pad)
Analg Dimming
VCC
R12
C4
R5
ISP
2
ISN
3
VC
4
GND
8
CREG
7
DRV
6
SENS
5
CTL
9
RVC
9
7
6
D1
SYNC
DCTL
ACTL
8 SS
CVC
COUT
RT8485
5 VC
Q1
RSENSE
ISN 4
CSS
L1
DRV
14
GATE
6
SENS
M1
OVP 10
RSET 1
GBIAS 13
GND
12
RSW
CB
RSW
AN034
RSET
ISW
ISP
ISN
VC
ACTL
DCTL
14
2
13
3
12
4
11
5
10
6
9
7
8
GATE
GBIAS
GND
VCC
OVP
SYNC
SS
SOP-14
SOP-8 (Exposed Pad)
50V high current Buck LED driver
LEDs
150V High power Buck LED Driver
© 2015 Richtek Technology Corporation
13
Application Note
Power Switch and DDR termination regulator
P/N
RT2528
Description
Power Switch with adj.ILIM
IOUT
0.5A~2.5A
VIN
2.5V~5.5V
Key Features





AEC-Q100 Grade 3
Adjustable current limit: 0.5A~2.5A via an ext. resistance
120mΩ P-MOSFET
Built-in Soft-Start
Low supply current:120µA
Package
PSOP-8
 Reverse input-out voltage
RT2526Q
DDR Termination regulator
DDRII/III:2A
VIN:3.1V~3.6V
VLDOIN:1.2V~1.8V
 3T Grade
 S3, S5 off modes
 MLCC stable
PSOP-8
 Remote sense
Richtek Technology Corporation
st
14F, No. 8, Tai Yuen 1 Street, Chupei City
Hsinchu, Taiwan, R.O.C.
Tel: 886-3-5526789
Richtek products are sold by description only. Richtek reserves the right to change the circuitry and/or specifications without notice at any time. Customers should obtain the latest relevant information and data sheets
before placing orders and should verify that such information is current and complete. Richtek cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Richtek product.
Information furnished by Richtek is believed to be accurate and reliable. However, no responsibility is assumed by Richtek or its subsidiaries for its use; nor for any infringements of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Richtek or its subsidiaries.
AN034
© 2015 Richtek Technology Corporation
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