The document discusses wide input voltage (wide Vin) DC-DC converters, highlighting their use in industrial, automotive, and communications systems where input voltages can vary widely and experience transients. It presents challenges faced in these applications and how Texas Instruments' wide Vin controllers and integrated modules address issues like reliability across voltage ranges, overload protection, and high power density with low EMI. Examples are given of wide Vin solutions for isolated bias supplies, boost converters, and automotive systems dealing with start-stop events and battery voltage variations.

1. Wide Vin DC/DC Converters:
Reliable Power for Demanding
Applications

2.  This webinar will be available afterwards at
www.designworldonline.com & email
 Q&A at the end of the presentation
 Hashtag for this webinar: #DWwebinar
Before We Start

3. Moderator Presenter
Mary Gannon
Design World
Jim MacDonald
Texas Instruments

4. Wide Vin DC/DC Converters
Reliable Power Solutions for Demanding Applications

5. • Wide Vin DC/DC converter overview
• Wide Vin power for Industrial systems
• Wide Vin power for Automotive systems
• Wide Vin power for Communications systems
• Additional Wide Vin resources
Agenda

6. TI’s Wide Vin DC/DC Converter Products
Reliable Power Solutions for Demanding Applications
Applications Power Challenges Products
Industrial
12V, 24V & higher Bus Voltages
Automotive & Transportation
12V/24V off-battery systems
Communications
24V/48V battery-backed systems
Multiple Input Sources
Varying Input Voltages
Large transients and/or noisy
& harsh conditions
Boost and Buck-boost
Controllers and Regulators
Buck Controllers & Regulators
Integrated Power Modules

7. Vin (V)
100V
80V
60V
40V
20V
Commercial
Auto
Consumer
Auto
Mass Transit
(Busses, Trains)
Avionics
& Defense
Factory
Automation
BTS
Repeaters
Base
Stations
Networking
& Storage
Automotive Industrial Comms & Cloud
10V
12V
24V 24V
28V
24V 24V
48V 48V
Nominal bus voltage
Bus operating range
Potential transient range
Auto start-stop range
4-20mA loop range
Wide Vin Benefit:
Optimized for Use Across Multiple Markets and Applications

8. Vin (V)
100V
80V
60V
40V
20V
Commercial
Auto
Consumer
Auto
Mass Transit
(Busses, Trains)
Avionics
& Defense
Factory
Automation
BTS
Repeaters
Base
Stations
Networking
& Storage
Automotive Industrial Comms & Cloud
10V
12V
24V 24V
28V
24V 24V
48V 48V
Nominal bus voltage
Bus operating range
Potential transient range
Auto start-stop range
4-20mA loop range
Wide Vin Benefit:
Optimized for Use Across Multiple Markets and Applications

9. Vin (V)
100V
80V
60V
40V
20V
Commercial
Auto
Consumer
Auto
Mass Transit
(Busses, Trains)
Avionics
& Defense
Factory
Automation
BTS
Repeaters
Base
Stations
Networking
& Storage
Automotive Industrial Comms & Cloud
10V
12V
24V 24V
28V
24V 24V
48V 48V
Nominal bus voltage
Bus operating range
Potential transient range
Auto start-stop range
4-20mA loop range
Wide Vin Benefit:
Optimized for Use Across Multiple Markets and Applications

10. Wide Vin Benefit:
High Voltage Rating Eliminates Protection Circuits & Saves PCB Area
VIN
DC/DCVIN_BAT
RTN
VIN
DC/DC
VIN_BAT
RTN
VIN
Wide Vin
DC/DC
VIN_BAT
RTN
Transient Absorbers Disconnect FET Wide Vin DC-DC
Pro:
• Does not interrupt dc/dc power during
OV transients
Pro:
• Not dissipative OV protection. Can
survive for longer duration OV conditions.
Pro:
• Automatic OV protection up to 65V/75V
• Operation not interrupted in OV condition
• No extra design work required.
Cons:
• Selection can be complicated;
Dependent on energy (Volt/time)
• Dissipates energy (bigger size)
• Longer duration OV (e.g. ISO 7637
Pulse 5b) conditions not taken care of
in reasonable size/cost
Cons:
• Needs multiple components including a
disconnect FET.
• Creates voltage drop (power dissipation)
in normal operation.
• PMOS tends to be bigger. NMOS needs
charge pump.
• Interrupts power flow during OV
Cons:
• May exhibit slightly lower efficiency when
operating from lower input voltages such
as 3.3V and 5V

11. Wide Vin Power for
Industrial Systems

12. Challenge #1: Designing a Reliable & Low Cost System Bias Supply
System
Bias
Supply
Digital
Isolator
• The system bias rail(s) must be derived from the system backplane,
which is typically 24V but can experience transients of 40V or higher
• Isolation is often required for noise immunity or safety
• The use of opto-isolators is often avoided due to reliability
Industrial Automation Equipment
System Need: Application Challenges:
• Most systems require a low current bias supply
for the micro-controller and/or FPGA to initiate
system start-up correctly each time

13. Wide Vin Bias Supply System Examples
36-75Vin Vout
LM5112LM5017
9VPRI 9VSEC
Digital
Controller
UCD3138
LM5101
LM5017
Flybuck SW1
SW1
M
DR_HS
DR_LS
-VEE
+VCC
-VEE
+VCC
Vin
Isolated bias supply for
DC/DC power modules
Isolated bias supply for
IGBT-based AC motor drives
Multi-output bias supply
for PLC I/O modules

14. LM5017/8/9 Fly-buck™ Bias Supply ICs
+
+
+
+
VI
N
BST
RON
RTN
SW
VCC
FB
UVLO
VIN
VOUT1
VOUT2
RFB1
RUV1
RON
COUT1
CBST
D1
CIN
COUT2
RFB2
RUV2
X1
Rr
NP
NSLM5017
CVCC
+
D2
LM5017 Feature System Benefits
7.5V to 100V operating range Works with all major bus voltages
Integrated synchronous FETs High efficiency, fewer components
Constant on-time (COT) architecture No loop compensation needed
100/300/600mA current rating Addresses bias needs up to ~6W
Switching frequency up to 1MHz Reduces PCB footprint
Ultra-fast transient response Fewer output capacitors needed
Isolated bias w/ no opto-isolator Higher reliability, fewer components
+
+
+
VIN
BST
RON
RTN
SW
VCC
FB
VIN
VOUT
RFB1
Rr
RUV1
RON
COUT
CBST
CIN
RFB2
RUV2
L
UVLO
+
CVCC
LM5017
Input Voltage (V)
MaxOutputCurrent(mA)
10048
LM5017LM25017
LM5018LM25018
LM5019LM25019
7.5
100
300
600
Synchronous Buck Circuit
Small & efficient bias supply from a 24V or 48V input bus
Isolated Fly-buck Circuit
Ideal for isolated and multi-output bias supplies; no opto needed!

15. Fly-buck Isolated Bias Supply Basics
Flybuck
Buck
+
-Vin
Vout
Vin
Vpri
Vsec
1
N
• The Fly-buck converter is evolved from a synchronous buck converter by adding
coupled windings to the inductor to have flyback-like isolated outputs.
• The isolated outputs can be multiple by adding more secondary windings to the
transformer
• A simple and low part count solution for multi-output/isolated power supply design

16. Flybuck Flyback
Outputs
Multiple isolated and one non-isolated
Isolated outputs can be negative
Same capabilities
Input Range Vin-min must be > primary output Vin-min smaller or larger than Vout
Size Smaller solution, smaller transformer
Cost Fewer component count, lower cost
Transformer 2-winding transformer 3-winding transformer larger and more expensive
FET Switch
Stress
Vin Vin + Vout/N
Performance
Good regulation achievable, 5% on
both primary and secondary outputs
Similar regulation through tertiary winding.
High output accuracy using opto, but large
deviation under light load condition
Fly-buck vs. Flyback Solution Comparison: Summary
• The Fly-buck can provide a simple, small and cost effective power solution
making it a suitable flyback alternative

17. • The Fly-buck can provide a simple, small and cost effective power
solution making it suitable as a flyback alternative (typically)
• A Fly-buck vs. Flyback Comparison:
o Spec: Nominal Vin=24V, Vo1=12V, Vo2=-12V, 250mA max load on each output
Fly-buck
 1:1 single secondary winding
transformer
 Primary side regulation
 Primary: 12V, non-isolated
 Secondary: -12V, isolated
Flyback
 1:1:1 two secondary
windings transformer
 Secondary side regulation
through opto-coupler
 Secondary: +/-12V, isolated
Fly-buck vs. Flyback Solution Comparison: Case Study

18. Fly-buck vs. Flyback Solution Comparison: PCB Design
LM5017 Flybuck
 Component Count 23
 Effective Area 1.4x1.2 inch
 Max height: 8mm
LM5000 Flyback
 Component Count 45
 Effective Area 1.8x1.8 inch
 Max height: 10mm
Fly-buck offers a smaller
solution size vs. Flyback
Fly-buck uses fewer
components than the Flyback,
and no opto-isolator is needed.
Effective
Area
Effective
Area

19. Fly-buck vs. Flyback Solution Comparison: Performance
LM5017 Flybuck
10.600
10.800
11.000
11.200
11.400
11.600
11.800
12.000
0.000 0.050 0.100 0.150 0.200 0.250
Vo(V)
Io1=Io2 (A)
Vo1
-Vo2
Vo2 has an additional
diode drop, and the
delta grows bigger at
higher load
4%Δ
11.600
11.700
11.800
11.900
12.000
12.100
0.000 0.050 0.100 0.150 0.200 0.250
Vo(V)
Io1=Io2 (A)
Vo1
-Vo2
LM5000 Flyback
Vo2 is lower at light
load, but it can be
improved by adding
pre-load
78.1%
83.8%
86.4%
87.7% 87.9%
73.3%
81.5%
84.5%
86.2% 87.1%
70.0%
75.0%
80.0%
85.0%
90.0%
0.000 0.050 0.100 0.150 0.200 0.250
Efficiency
Io1=Io2 (A)
Flybuck
Flyback
+2%
Vo1 and Vo2 are equally loaded from 0A to 250mA
Flybuck can achieve +/-5% accuracy under balanced load, and has slightly higher efficiency than Flyback

20. Challenge #2: Designing a Boost Supply with Overload Protection
Traditional boost solutions:
• Require fuse and/or hotswap controllers to
protect against inrush or over-current faults
• Fuses require system service after a fault
• Interaction between ICs must be considered
Hot swap
controller
Boost
controller
Load
Optional
fuse
SUPPLY
Boost controller w/
disconnect switch Load
Boost with Disconnect Switch:
• Limits inrush current during start-up and overloads
• Eliminates the need for hot swap controllers
• Disconnects the load during catastrophic faults
• Avoids unnecessary fuse replacements
• Reduces system cost & footprint
System Need: Application Challenges:
SUPPLY
• Ability to power motors without
reducing system reliability
• Boost converters inherently have no overload or short-
circuit protection (current can flow from input to output

21. System Examples Where Load Disconnect is Needed
DC/DC
LM5121
24V@2A
12V
Supply Print Motor
Point-of-sale systems Currency handler
Industrial injection molding machine

22. LM5121 Synchronous Boost Controller with Disconnect Switch
VCC
LM5121
CSN
DG
SYNCIN/RT
RES
SSUVLO
VIN
AGND
BST
MODE
PGND
SLOPE
COMP
FB
HO
LO
SW
+
DS
VOUTVSUPPLY
CSP
Disconnect
Switch
LM5121 Feature System Benefits
Wide input voltage range: 4.5V to 65V
Output voltage: adjustable up to 100V
Supports high voltage input and output with
no external protection circuitry needed
Synchronous operation High efficiency, bypass operation (Vout = Vin)
Load disconnect FET Input to output isolation during shutdown
Inrush current limit Avoid unnecessary input fuse replacements
Hiccup mode over-current protection Protects against temporary over-load faults
Circuit breaker function Disconnects catastrophic faults from input
VOUT
VIN
The disconnect FET enabled a back-to-back MOSFET
connection that isolates the load from the source during
output fault conditions and eliminates the need for a fuse
LM5121 Eval Board with
input disconnect FET

23. +
-
CS
AMP
A=10
RS
Circuit Breaker
Comparator
1.6V/0.11V
+
-
LM5121
+
VIN
CSP CSN DG DS
Disconnect
Switch
Sense
Resistor
• If the voltage across the sense
resistor exceeds the circuit breaker
threshold (~160mV), the internal
comparator and FET will quickly turn
off the external disconnect FET
• When the sense resistor voltage
drops below circuit breaker disable
threshold (~10mV), the disconnect
FET is turned on again
Circuit Breaker Function
Protects against output short-circuits and other catastrophic faults
How does it work?

24. Challenge #3: Achieving High Power Density and Low EMI
System Need: Application Challenges:
• High density power circuits that
free up valuable PCB real estate
for critical system functions
• Discrete power ICs require multiple external components
and can be complex to design & debug
• Integrated DC/DC converter modules can be difficult to
manufacture (hidden connections are difficult to inspect)
• Power circuits (in general) generate EMI that can degrade
performance of sensitive system signals
LGA Power Modules
• Can be difficult to manufacture
(hard to inspect all connections)
Discrete DC/DC Converter
• More complex design/layout
Many systems have
minimal PCB area left
for the power circuits

25. LMZ1/2 Power Modules: High Performance and Easy to Design
1A 2A 3A 4A 5A
Current
8A 10A
LMZ10504 (≈42oC case) Competitors (≈46oC case)
Operating Conditions: VIN=5.0V, VOUT=1.8V, IOUT= 4A
LMZ13610
6-36Vin, 10A
Demo board
Fully WEBENCH® enabled for easy design
Simulation, thermal analysis, and
Easy-to-use leaded packages
• Single exposed pad with IC leads
• Easy prototyping and manufacturing
High PCB Density
As few as 5 external components
Low Radiated EMI
Meets EN55022 Class B
Best-in-class Thermal Performance
No airflow or heat sink required

26. Wide Vin Power for
Automotive Systems

27. Challenge #1: Handling the Automotive Battery Range
Compliance to load dump and cold cranking requires a wide input range
40V for 12V batteries
60V for 24V battery
As low as 3V
Automotive battery voltage transients
12V Lead Acid Battery Application Challenges
• Battery voltage varies due to engine cranking, load
dump, jump starts, and accidental reverse battery
connection
– Cold crank voltage < 5V
– Load dumps cause 40V transients
– 24V commercial vehicle load dump transients
can exceed 60V
Wide Vin power management ICs can increase reliability and reduce system cost

28. Wide Vin Power Solutions for Automotive
Protection
Battery
conditioning
Buck
converters
PMU
Typ 8V, 5V or 3.3V
Wide Vin
converters &
controllers
Voltage
reference
Boost
3V-42V
E.g. 10V min
boost output
Optional reverse
polarity or over-
voltage/current
protection
Boost or buck-boost
needed if output
voltage level must be
maintained during
cranking
Wide Vin buck
converter is needed
here to survive
battery voltage
transients
Battery:
12 or 24V
Standard
Vin
<28V
Wide Vin
required
≥28V
LDOs

29. Challenge #2: Dealing with Start-stop
• Automotive manufacturers will add Idle start-
stop (ISS) capability to increase fuel efficiency
• ~15M vehicles will have ISS by 2015
Market Need: Application Challenges:
• A start-stop event could push the battery voltage as
low as 3V (similar to a warm crank condition)
• Vehicles must maintain a stable ~12V output to
ensure normal AVN operation despite voltage drops
• Must be scalable to address different system needs;
<100W for sub-systems up to ≥400W for a centralized
voltage stabilizer system for the whole vehicle
• Small form factor: must not add significant size or
weight to the vehicle or sub-system
Voltage
Stabilizer
Boost
3V-42V
E.g. 10V min
boost output
12V Battery
To power
system or
sub-system

30. LM5122: Stackable Synchronous Boost Controller
MASTER
VCCCSN
SYNCIN/RT
RES
SS
UVLO
VIN
SYNCOUT
BST
SLOPE
COMP
FB
HO
LO
SW
+
VOUT
VCCCSN
SYNCIN/RT
RES
SS
UVLO
VIN
BST
SLOPE
COMP
FB
HO
LO
SW
VCC
SLAVE
VSUPPLY
VSUPPLY
CSP
CSP
OPT
OPT
LM5122 Feature System Benefits
Wide Vin range: 4.5V to 65V
(3V after start-up)
Handles load dump and start-stop voltage range
Synchronous operation High efficiency, bypass operation (Vout = Vin)
Stackable w/ current sharing Scales easily from 1-phase to 8+ phases
100% duty cycle bypass mode Low dropout when not boosting battery voltage
Low shutdown current: 9uA Low battery drain when not operating
LM5122EV-1PH: 1-phase design for ≤100W
PMP7837: 4-phase ref design for 450W
Up to 98% Efficiency! Scalable from 1 to 4+ phases!
http://www.ti.com/tool/PMP7837
http://www.ti.com/tool/lm5122evm-1ph

31. Challenge #3: Fitting Wide Vin Power in Tight Spaces
Application example: rear-view camera module
• Total solution size must fit into tiny space
• Operates directly from battery; cold crank
down to 4.5V and load-dump up to 42V
• High efficiency (low thermal dissipation)
• Does not interfere with radio frequency band
• Low EMI to avoid degrading video quality
The National Highway Traffic Safety
Administration will require all vehicles to have
a rear-view visibility system starting in May
2018
Market Need: Application Challenges:

32. Wide Vin Power Solution for Rear-view Cameras
DS90UB913A-Q1
Serializer
LM34919C
2.9V Buck
Converter
TPS62231
1.8V Buck
Converter
RC
Filters
Aptina
AR0132AT
Image Sensor
12bit Data &
PixCLK, FV, LV
Aptina
AP0101AT
Image Signal
Processor (ISP)
10bit
Data &
PixCLK,
FV, LV
VDD, IOVDD, IO
VAA
VDD, IO
2.9V 1.8V
2.8V
12V
SMB Conn.
Coaxial
Cable
Power
FPD-Link III
Serial Data
Power/Serializer Board Camera Board
Power/Serializer Front Power/Serializer B
Camera Board Front Camera Board B
Power/Serializer Front Power/Serializer Back
Camera Board Front Camera Board Back
http://www.ti.com/tool/PMP9300
TI DESIGN:
Schematic/BOM/Gerber On line
VIN
SW
BST
LM34919C
VCC
SS
RON
4.5V - 40V
Input
C1 RON
R2
R1
C2
VOUT
L1
C3
C4
D1
C6
RTN
ISEN
SGND
FB
PGD R3PGOOD
VDD
SHUTDOWN
Key Challenge LM34919CQ Benefits
Small package size 1.75x2mm uSMD package
Wide Vin range 4.5V to 50V input works from battery
Low part count Constant on time topology minimizes
external components
No AM interference 2.6MHz switching frequency
Low EMI Meets CISPR 25 Class 5
~22mm
Ultra small
package
(1.75x2mm)

33. Wide Vin Power for
Communications Systems

34. Challenge #1: High Current Power From a 48V Bus
• Generally constant frequency is desired
(for minimizing/managing switching
noise)
• Potential for high step-down ratios
(low duty cycles)
• Efficiency and complexity choices
(1-stage vs. 2-stage conversion)
• Transient response
(trying to minimize number of capacitors)
• Stability over all operating conditions
Creating a high current system supply from a
high input voltage (36V or 48V)
System Need: Application Challenges:
48V
Buck DC/DC
Buck DC/DC
28V
(PA #1)
24V
(Antenna)
Isolated
Power
Module
12V (to
uP board)
Buck DC/DC
5V/3.3V
(Misc)

35. Selecting the Right Wide Vin Buck Controller
High Duty Cycle
Low Duty Cycle
More stable
Fast Transients
Current sharing
More
flexible
Benefits:
• Inherent feed-forward
• Simpler loop compensation
Considerations/tradeoffs:
• Can be noise sensitive
• Not ideal for high Vin to low Vout
Benefits:
• Inherent feed-forward
• Simpler loop compensation
• Eliminates leading edge “spike”
(excellent for high Vin to low Vout)
Considerations/tradeoffs:
• Max frequency and duty cycle limits
Voltage Mode
Benefits:
• Good regulation & noise margin
• More “tunable” for specific needs
Considerations/tradeoffs:
• Need feed-forward if Vin can change
• Tougher to compensate loop
• Current sharing needs extra circuitry
Top Parts:
TPS40170
TPS40200
Top Parts:
TPS43340
TPS43350
Current Mode
Constant On-time (or DCAP)
Benefits:
• Easy to use (no loop compensation)
• Fast transient response
Considerations/tradeoffs:
• Not constant frequency
• Not synchronizable
• Requires ripple to regulate
Top Parts:
LM3150
LM5085
Emulated Current Mode
Top Parts:
LM5116
LM5117
LM5119
LM5008

36. TI’s Most Popular Wide-Vin Buck Controllers
Devices for operation from <60V supply
Devices optimized for supplies up to 75V/100V

37. Part Number Package
BVDSS
(V)
VGS
(V)
RDS(ON)
Typ (10V)
(mΩ)
RDS(ON)
Max (10V)
(mΩ)
ID @
25ºC
(silicon)
Qg(10)
Typ
(nC)
Qgd
Typ
(nC)
Qgs
Typ
(nC)
Qrr -
300A/µs
Typ
(nC)
Coss
Typ
(pF)
Alpha
Samples
RTM
CSD18509Q5B SON5x6 40 20 1.0 1.25 264 160 21.0 34.0 40 1100 30-Jan 14Q2
CSD18502Q5B SON5x6 40 20 1.8 2.3 204 52 8.4 10.3 88 900 Now Now
CSD18501Q5A SON5x6 40 20 2.5 3.2 155 42 5.9 8.1 70 725 Now Now
CSD18503Q5A SON5x6 40 20 3.4 4.3 145 27 4.3 4.5 52 510 Now Now
CSD18504Q5A SON5x6 40 20 5.3 6.6 75 16 2.4 3.2 39 310 Now Now
CSD18540Q5B SON5x6 60 20 1.6 2.0 188 58 11.0 12.8 120 498 15-Feb 14Q2
CSD18532Q5B SON5x6 60 20 2.5 3.2 169 44 6.9 10.0 111 470 Now Now
CSD18532NQ5B SON5x6 60 20 2.7 3.4 165 49 7.9 16.0 139 495 Now Now
CSD18531Q5A SON5x6 60 20 3.5 4.6 134 36 5.9 6.9 100 380 Now Now
CSD18533Q5A SON5x6 60 20 4.7 5.9 103 29 5.4 6.6 68 292 Now Now
CSD18563Q5A SON5x6 60 20 6.0 7.5 98 29 5.4 6.6 57 292 Now Now
CSD18534Q5A SON5x6 60 20 7.8 9.8 69 17 3.5 3.2 54 167 Now Now
CSD18537NQ5A SON5x6 60 20 11 14 55 14 2.3 4.7 54 136 Now Now
CSD19502Q5B SON5x6 80 20 3.4 4.1 138 48 8.6 14 275 925 Now Now
CSD19532Q5B SON5x6 100 20 4.0 4.9 130 48 8.7 13 249 706 Now Now
CSD19531Q5A SON5x6 100 20 5.3 6.4 110 37 7.0 11 226 540 Now Now
CSD19533Q5A SON5x6 100 20 7.8 9.4 75 27 4.9 7.9 163 395 Now Now
CSD19534Q5A SON5x6 100 20 12.4 15.5 53 15 2.7 4.5 97 228 Now 10-Feb
60-100V NexFETs for Wide Vin Controller Applications
Ideal for
24V/36V
buck designs
up to 10A
High-side
Low-side
• Scalable from 40V to 100V
• Industry-standard SON 5x6mm package
• Ultra-low Qg and Qgd and low thermal resistance
Part Number Package
BVDSS
(V)
VGS
(V)
RDS(ON)
Typ (10V)
(mΩ)
RDS(ON)
Max (10V)
(mΩ)
ID @
25ºC
(silicon)
Qg(10)
Typ
(nC)
Qgd
Typ
(nC)
Qgs
Typ
(nC)
Qrr -
300A/µs
Typ
(nC)
Coss
Typ
(pF)
Alpha
Samples
RTM
CSD18509Q5B SON5x6 40 20 1.0 1.25 264 160 21.0 34.0 40 1100 30-Jan 14Q2
CSD18502Q5B SON5x6 40 20 1.8 2.3 204 52 8.4 10.3 88 900 Now Now
CSD18501Q5A SON5x6 40 20 2.5 3.2 155 42 5.9 8.1 70 725 Now Now
CSD18503Q5A SON5x6 40 20 3.4 4.3 145 27 4.3 4.5 52 510 Now Now
CSD18504Q5A SON5x6 40 20 5.3 6.6 75 16 2.4 3.2 39 310 Now Now
CSD18540Q5B SON5x6 60 20 1.6 2.0 188 58 11.0 12.8 120 498 15-Feb 14Q2
CSD18532Q5B SON5x6 60 20 2.5 3.2 169 44 6.9 10.0 111 470 Now Now
CSD18532NQ5B SON5x6 60 20 2.7 3.4 165 49 7.9 16.0 139 495 Now Now
CSD18531Q5A SON5x6 60 20 3.5 4.6 134 36 5.9 6.9 100 380 Now Now
CSD18533Q5A SON5x6 60 20 4.7 5.9 103 29 5.4 6.6 68 292 Now Now
CSD18563Q5A SON5x6 60 20 6.0 7.5 98 29 5.4 6.6 57 292 Now Now
CSD18534Q5A SON5x6 60 20 7.8 9.8 69 17 3.5 3.2 54 167 Now Now
CSD18537NQ5A SON5x6 60 20 11 14 55 14 2.3 4.7 54 136 Now Now
CSD19502Q5B SON5x6 80 20 3.4 4.1 138 48 8.6 14 275 925 Now Now
CSD19532Q5B SON5x6 100 20 4.0 4.9 130 48 8.7 13 249 706 Now Now
CSD19531Q5A SON5x6 100 20 5.3 6.4 110 37 7.0 11 226 540 Now Now
CSD19533Q5A SON5x6 100 20 7.8 9.4 75 27 4.9 7.9 163 395 Now Now
CSD19534Q5A SON5x6 100 20 12.4 15.5 53 15 2.7 4.5 97 228 Now 10-Feb

38. CSD18563Q5A
CSD18537NQ5A
Using a Wide Vin Controller with 60V NexFETs
VIN: 24V/36V
VOUT: 5V
IOUT: 5A
LOUT: 10µH (14mΩ)
Freq: 100kHz
• >92% Peak Efficiency with 36VIN/5VOUT
• >93% Peak Efficiency with 24VIN/5VOUT

39. Challenge #2: Low Noise Power for Sensitive Signals
• VCOs, RF circuits, and data converters
require low noise power supplies to
reach their stated performance
System Need: Application Challenges:
• DC/DC converters generate ripple that can degrade
the signal and/or reduce transmit/receive speed
• Linear regulators dissipate heat
0
10
20
30
40
50
60
70
80
10 100 1,000 10,000 100,000 1,000,000 10,000,000
PSRR[dB]
Frequency [Hz]
DAC9881 PSRR vs 5V (analog supply) Input Spectrum
0.00
0.01
0.10
1.00
10.00
100.00
1000.00
10 100 1K 10K 100K 1M 10M
Freq (Hz)
uV/sqrt(Hz)
If we used a DC/DC converter as the power supply, the ripple at
higher frequencies could degrade system performance as they
would not be properly filtered by the DAC alone.
For example, the PSRR on the DAC9881 is low at
higher frequencies. That means that it has a limited
ability to filter out any high frequency input ripple
and prevent it from affecting bits.

40. Know What to Look For in a Linear Regulator
 PSRR (in dB) denotes the LDO’s ability to reject noise from the input power supply.
The higher the absolute value, the better the LDO can attenuate ripple from the
input source, prohibiting it from affecting the output rail.
 Output noise voltage (µVRMS) represents the noise generated from the LDO itself.
The lower this value, the less impact the LDO will have on the integrity of the
desired output rail.
Creating a low noise
supply from >30V input
Filtering out power supply
noise (ripple)
Preventing any noise from
disrupting the signal
Best Used
When…
• Low current needed
• Don’t like switchers
• Need small size/cost
• High current needed
• Need high efficiency
• Need low ripple
• Low to medium current
• Radio signals involved
Key Specs to
review
Output noise should not
be too high
• Need high PSRR (at the
switching frequency)
• Look for lowest output noise
• Also want high PSRR over a
wide bandwidth
Don’t forget Every volt dropped
through the regulator
means efficiency loss
Try to minimize dropout to
keep heat down

41. VIN
EN
NR/SS
VOUT
FB
GND
COUT
TPS7A30
ON
OFF
CIN
VIN
EN
NR/SS
VOUT
FB
GND
TPS7A49
ON
OFF
CIN
VIN
EN
NR/SS
PH
VSense
GND
TPS54060ON
OFF
COUTVIN - 18V – 30V
+18V
-18V
+12V
-12V
-18V Switcher
@300kHz
+18V Switcher
@ 300kHz
-12V LDO
+12V LDO
By virtue of high PSRR and low output noise density,
TPS7A49 & TPS730 are able to filter out switching
noise and provide clean positive and negative rails
Filtering Switching Power Supply Noise (Ripple)
• For high current needs, the power dissipation of a linear regulator may be too high
• Combining a switching converter with a high PSRR linear regulator can achieve an
excellent balance of high efficiency and low noise

42. TPS7A40 LM2936HV TPS7A16 TPS709 TPS7A49 TPS7A30 TPS7A47 TPS7A33
IOUT (A) 0.05 0.05 0.1 0.15 0.15 0.2 1 1
VIN (V) 7-100 5.5-60 3-60 2.7-30 3-36 -3 to -36 3-36 -3 to -36
VOUT (V) 1.1-90 3-5 1.2-18.5 1.2-5 1.2-33 -1.18 to -33 1.4-34 -1.2 to -33
Output Noise 58uVrms 500uVrms - 190uVrms 12.7uVrms 14uVrms 4uVrms 16uVrms
PSRR @ 100kHz
65dB @
100Hz
60dB @ 120Hz
50dB @
100Hz
52dB @
1kHz
53dB 55dB 60dB 64dB
VOUT Accuracy (%) 2.5 +/-2 2 2 1.5 1 1
Dropout (mV)
780 @
50mA
200
265mV @
100mA
245 @
50mA
260mV @
100mA
215 @
100mA
307 @ 1A 307 @ 1A
Package
(bold: smallest)
8MSOP-
PowerPAD
SOT-223, 8SOIC,
8VSSOP, TO-252
8MSOP-
PowerPAD
6-SON
SOT-223
SOT-23
8MSOP-
PowerPAD
8MSOP-
PowerPAD
20-SON
20-SON
7-TO-220
Solution Size
3x5mm +
3 caps +
2 resistors
5mm x 3mm + 2
caps
3x5mm +
3 caps +
1 resistor
2x2mm +
2 caps
3x5mm +
4 caps +
2 resistors
3x5mm +
4 caps +
2 resistors
5x5mm +
3 caps
5x5mm +
3 caps
Wide Vin Linear Regulator Selection Guide Look for Wide Vin parts when the
input can experience transients
Pick parts with high PSRR when you
need to filter out switching noise
Look for parts with low output noise
when dealing with very sensitive RF
signals that require a low noise floor

43. Tools to Help You Start Your Next Wide Vin Circuit Design
Learn with Wide Vin Videos
Start a design today with
WEBENCH® Designer
Get design tips from TI
experts on E2E Power Forum
Jump start your system design with TI Designs
Order TI eval modules
optimized for your systems
LM27403
Tiny 30A POL Module
LM5017 Multi-output
Fly-buck EVM

44. For More Information
www.ti.com/WideVin

45. Thank You

46. Questions?
Mary Gannon
Design World
mgannon@wtwhmedia.com
Phone: 440.234.4531
Twitter: @DW_MaryGannon
Jim MacDonald
Texas Instruments
James.macdonald@ti.com
Phone: 669-721-7458

47. Thank You
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