TI LMZ14202HTZE/NOPB

LMZ14202H
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SNVS691D – JANUARY 2011 – REVISED FEBRUARY 2013
LMZ14202H 2A, SIMPLE SWITCHER® Power Module for High Output Voltage
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FEATURES
1
•
•
•
23
•
•
•
•
•
•
•
Integrated Shielded Inductor
Simple PCB Layout
Flexible Startup Sequencing Using External
Soft-start and Precision Enable
Protection Against Inrush Currents
Input UVLO and Output Short Circuit
Protection
– 40°C to 125°C Junction Temperature Range
Single Exposed Pad and Standard Pinout for
Easy Mounting and Manufacturing
Low Output Voltage Ripple
Pin-to-pin Compatible Family:
– LMZ14203H/2H/1H (42V Max 3A, 2A, 1A)
– LMZ14203/2/1 (42V Max 3A, 2A, 1A)
– LMZ12003/2/1 (20V Max 3A, 2A, 1A)
Fully Enabled for Webench® Power Designer
APPLICATIONS
•
•
•
•
Intermediate Bus Conversions to 12V and 24V
Rail
Time Critical Projects
Space Constrained / High Thermal
Requirement Applications
Negative Output Voltage Applications
Figure 1. Easy to use 7 pin package
PFM 7 Pin Package
10.16 x 13.77 x 4.57 mm (0.4 x 0.542 x 0.18 in)
θJA = 16°C/W, θJC = 1.9°C/W
RoHS Compliant
ELECTRICAL SPECIFICATIONS
•
•
•
•
Up to 2A Output Current
Input Voltage Range 6V to 42V
Output Voltage as Low as 5V
Efficiency up to 97%
PERFORMANCE BENEFITS
•
•
•
•
High Efficiency Reduces System Heat
Generation
Low Radiated EMI(EN 55022 Class B
Compliant) (1)
No Compensation Required
Low Package Thermal Resistance
DESCRIPTION
The LMZ14202H SIMPLE SWITCHER power module
is an easy-to-use step-down DC-DC solution capable
of driving up to 2A load with exceptional power
conversion efficiency, line and load regulation, and
output accuracy. The LMZ14202H is available in an
innovative
package
that
enhances
thermal
performance and allows for hand or machine
soldering.
The LMZ14202H can accept an input voltage rail
between 6V and 42V and deliver an adjustable and
highly accurate output voltage as low as 5V. The
LMZ14202H only requires three external resistors
and four external capacitors to complete the power
solution. The LMZ14202H is a reliable and robust
design with the following protection features: thermal
shutdown, input under-voltage lockout, output overvoltage protection, short-circuit protection, output
current limit, and allows startup into a pre-biased
output. A single resistor adjusts the switching
frequency up to 1 MHz.
(1)
EN 55022:2006, +A1:2007, FCC Part 15 Subpart B: 2007.
1
2
3
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
SIMPLE SWITCHER is a registered trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2011–2013, Texas Instruments Incorporated
LMZ14202H
SNVS691D – JANUARY 2011 – REVISED FEBRUARY 2013
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System Performance
Efficiency VOUT = 12V
100
EFFICIENCY (%)
95
90
85
80
VIN = 15V
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
75
70
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Thermal Derating VOUT = 12V, θJA = 16°C/W
OUTPUT CURRENT (A)
2.5
2.0
1.5
1.0
0.5
VIN = 15V
VIN = 24V
VIN = 42V
0.0
-20
0 20 40 60 80 100 120 140
AMBIENT TEMPERATURE (°C)
Radiated Emissions (EN 55022 Class B)
RADIATED EMISSIONS (dB V/m)
80
Emissions (Evaluation Board)
EN 55022 Limit (Class B)
70
60
50
40
30
20
10
0
0
2
200
400
600
800
FREQUENCY (MHz)
1000
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SNVS691D – JANUARY 2011 – REVISED FEBRUARY 2013
Simplified Application Schematic
VOUT
FB
SS
EN
GND
VIN
VIN
RON
LMZ14202H
VOUT
30V
24V
18V
15V
12V
5V
RFBT
34 k:
34 k:
34 k:
34 k:
34 k:
34 k:
RFBB
931:
1.18 k:
1.58 k:
1.91 k:
2.43 k:
6.49 k:
RON
COUT
619 k: 33 PF
499 k: 33 PF
374 k: 33 PF
287 k: 47 PF
249 k: 47 PF
100 k: 100 PF
COUT-ESR
1-75 m:
1-60 m:
1-60 m:
1-65 m:
1-75 m:
1-145 m:
VIN
34 - 42V
28 - 42V
22 - 42V
18 - 42V
15 - 42V
8 - 42V
VOUT
CFF
RON
0.022 PF
VIN
CIN
10 PF
* RENT
RFBT
CSS
4700 pF
* RENB
COUT
RFBB
* See equation 1
to calculate values
Connection Diagram
Exposed Pad
Connect to GND
7
6
5
4
3
2
1
VOUT
FB
SS
GND
EN
RON
VIN
Figure 2. Top View
7-Lead PFM
PIN DESCRIPTIONS
Pin
Name
Description
1
VIN
Supply input — Additional external input capacitance is required between this pin and the exposed pad (EP).
2
RON
On time resistor — An external resistor from VIN to this pin sets the on-time and frequency of the application. Typical
values range from 100k to 700k ohms.
3
EN
4
GND
5
SS
Soft-Start — An internal 8 µA current source charges an external capacitor to produce the soft-start function.
6
FB
Feedback — Internally connected to the regulation, over-voltage, and short-circuit comparators. The regulation reference
point is 0.8V at this input pin. Connect the feedback resistor divider between the output and ground to set the output
voltage.
7
VOUT
EP
EP
Enable — Input to the precision enable comparator. Rising threshold is 1.18V.
Ground — Reference point for all stated voltages. Must be externally connected to EP.
Output Voltage — Output from the internal inductor. Connect the output capacitor between this pin and the EP.
Exposed Pad — Internally connected to pin 4. Used to dissipate heat from the package during operation. Must be
electrically connected to pin 4 external to the package.
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
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LMZ14202H
SNVS691D – JANUARY 2011 – REVISED FEBRUARY 2013
Absolute Maximum Ratings
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(1) (2)
VIN, RON to GND
-0.3V to 43.5V
EN, FB, SS to GND
-0.3V to 7V
Junction Temperature
150°C
Storage Temperature Range
-65°C to 150°C
ESD Susceptibility (3)
± 2 kV
Peak Reflow Case Temperature
(30 sec)
245°C
For soldering specifications, refer to the following document: www.ti.com/lit/snoa549c
(1)
(2)
(3)
Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which
operation of the device is intended to be functional. For guaranteed specifications and test conditions, see the Electrical Characteristics.
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
The human body model is a 100pF capacitor discharged through a 1.5 kΩ resistor into each pin. Test method is per JESD-22-114.
Operating Ratings
(1)
VIN
6V to 42V
EN
0V to 6.5V
−40°C to 125°C
Operation Junction Temperature
(1)
Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which
operation of the device is intended to be functional. For guaranteed specifications and test conditions, see the Electrical Characteristics.
Electrical Characteristics
Limits in standard type are for TJ = 25°C only; limits in boldface type apply over the junction temperature (TJ) range of -40°C
to +125°C. Minimum and Maximum limits are guaranteed through test, design or statistical correlation. Typical values
represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise
stated the following conditions apply: VIN = 24V, VOUT = 12V, RON = 249kΩ
Symbol
Parameter
Conditions
Min
Typ
Max
1.10
1.18
1.25
(1)
(2)
(1)
Units
SYSTEM PARAMETERS
Enable Control
VEN
VEN-HYS
EN threshold trip point
VEN rising
EN threshold hysteresis
90
V
mV
Soft-Start
ISS
ISS-DIS
SS source current
VSS = 0V
8
SS discharge current
10
15
-200
µA
µA
Current Limit
ICL
Current limit threshold
DC average
2.4
3.2
3.95
A
VINUVLO
Input UVLO
EN pin floating
VIN rising
3.75
V
VINUVLO-HYST
Hysteresis
EN pin floating
VIN falling
130
mV
ON timer minimum pulse width
150
ns
OFF timer pulse width
260
ns
VIN UVLO
ON/OFF Timer
tON-MIN
tOFF
Regulation and Over-Voltage Comparator
(1)
(2)
4
Min and Max limits are 100% production tested at 25°C. Limits over the operating temperature range are guaranteed through correlation
using Statistical Quality Control (SQC) methods. Limits are used to calculate Average Outgoing Quality Level (AOQL).
Typical numbers are at 25°C and represent the most likely parametric norm.
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SNVS691D – JANUARY 2011 – REVISED FEBRUARY 2013
Electrical Characteristics (continued)
Limits in standard type are for TJ = 25°C only; limits in boldface type apply over the junction temperature (TJ) range of -40°C
to +125°C. Minimum and Maximum limits are guaranteed through test, design or statistical correlation. Typical values
represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise
stated the following conditions apply: VIN = 24V, VOUT = 12V, RON = 249kΩ
Symbol
VFB
VFB
VFB-OVP
Min
Typ
Max
(1)
Units
VIN = 24V, VOUT = 12V VSS >+ 0.8V
TJ = -40°C to 125°C
IOUT = 10mA to 2A
0.782
0.803
0.822
V
VIN = 24V, VOUT = 12V VSS >+ 0.8V
TJ = 25°C
IOUT = 10mA to 2A
0.786
0.803
0.818
V
VIN = 36V, VOUT = 24V VSS >+ 0.8V
TJ = -40°C to 125°C
IOUT = 10mA to 2A
0.780
0.803
0.824
V
VIN = 36V, VOUT = 24V VSS >+ 0.8V
TJ = 25°C
IOUT = 10mA to 2A
0.787
0.803
0.819
V
Parameter
Conditions
In-regulation feedback voltage
In-regulation feedback voltage
Feedback over-voltage protection
threshold
(1)
(2)
0.92
V
IFB
Feedback input bias current
5
nA
IQ
Non Switching Input Current
VFB= 0.86V
1
mA
ISD
Shut Down Quiescent Current
VEN= 0V
25
μA
Rising
165
°C
15
°C
4 layer Printed Circuit Board, 7.62cm x
7.62cm (3in x 3in) area, 1 oz Copper, No
air flow
16
°C/W
4 layer Printed Circuit Board, 6.35cm x
6.35cm (2.5in x 2.5in) area, 1 oz Copper,
No air flow
18.4
°C/W
No air flow
1.9
°C/W
Thermal Characteristics
TSD
TSD-HYST
θJA
θJC
Thermal Shutdown
Thermal Shutdown Hysteresis
Junction to Ambient
Junction to Case
PERFORMANCE PARAMETERS
ΔVOUT
Output Voltage Ripple
VOUT = 5V, CO = 100µF 6.3V X7R
ΔVOUT/ΔVIN
Line Regulation
VIN = 16V to 42V, IOUT= 3A
.01
8
%
ΔVOUT/ΔIOUT
Load Regulation
VIN = 24V, IOUT = 0A to 2A
1.5
mV/A
η
Efficiency
VIN = 24V VOUT = 12V IOUT = 1A
93
%
η
Efficiency
VIN = 24V VOUT = 12V IOUT = 2A
92
%
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PP
5
LMZ14202H
SNVS691D – JANUARY 2011 – REVISED FEBRUARY 2013
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Typical Performance Characteristics
Unless otherwise specified, the following conditions apply: VIN = 24V; Cin = 10uF X7R Ceramic; CO = 47uF; TAMB = 25°C.
95
2.5
90
85
80
VIN = 8V
VIN = 12V
VIN = 24V
VIN = 36V
VIN = 42V
70
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
1.5
1.0
0.5
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 3.
Figure 4.
Efficiency VOUT = 12V TAMB = 25°C
Power Dissipation VOUT = 12V TAMB = 25°C
100
3.0
95
2.5
90
85
80
VIN = 15V
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
75
70
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
VIN = 15V
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
2.0
1.5
1.0
0.5
0.0
0.0
2.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 5.
Figure 6.
Efficiency VOUT = 15V TAMB = 25°C
Power Dissipation VOUT = 15V TAMB = 25°C
100
3.0
95
2.5
90
85
80
75
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
0.0
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
2.0
1.5
1.0
0.5
0.0
70
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 7.
6
VIN = 8V
VIN = 12V
VIN = 24V
VIN = 36V
VIN = 42V
0.0
2.0
POWER DISSIPATION (W)
EFFICIENCY (%)
POWER DISSIPATION (W)
3.0
75
EFFICIENCY (%)
Power Dissipation VOUT = 5.0V TAMB = 25°C
POWER DISSIPATION (W)
EFFICIENCY (%)
Efficiency VOUT = 5.0V TAMB = 25°C
100
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 8.
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SNVS691D – JANUARY 2011 – REVISED FEBRUARY 2013
Typical Performance Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V; Cin = 10uF X7R Ceramic; CO = 47uF; TAMB = 25°C.
Power Dissipation VOUT = 18V TAMB = 25°C
3.0
95
2.5
POWER DISSIPATION (W)
EFFICIENCY (%)
Efficiency VOUT = 18V TAMB = 25°C
100
90
85
80
75
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
0.5
1.0
1.5
OUTPUT CURRENT (A)
1.0
0.5
0.0
2.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 10.
Efficiency VOUT = 24V TAMB = 25°C
Power Dissipation VOUT = 24V TAMB = 25°C
100
3.0
95
2.5
POWER DISSIPATION (W)
EFFICIENCY (%)
1.5
Figure 9.
90
85
80
75
VIN = 28V
VIN = 30V
VIN = 36V
VIN = 42V
0.0
VIN = 28V
VIN = 30V
VIN = 36V
VIN = 42V
2.0
1.5
1.0
0.5
0.0
70
0.5
1.0
1.5
OUTPUT CURRENT (A)
0.0
2.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 11.
Figure 12.
Efficiency VOUT = 30V TAMB = 25°C
Power Dissipation VOUT = 30V TAMB = 25°C
100
3.0
95
2.5
POWER DISSIPATION (W)
EFFICIENCY (%)
2.0
0.0
70
0.0
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
90
85
80
75
70
0.0
VIN = 34V
VIN = 36V
VIN = 42V
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
1.5
1.0
0.5
VIN = 34V
VIN = 36V
VIN = 42V
0.0
2.0
Figure 13.
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 14.
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SNVS691D – JANUARY 2011 – REVISED FEBRUARY 2013
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Typical Performance Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V; Cin = 10uF X7R Ceramic; CO = 47uF; TAMB = 25°C.
95
2.5
90
85
80
70
0.0
VIN = 8V
VIN = 12V
VIN = 24V
VIN = 36V
VIN = 42V
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
1.5
1.0
0.5
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 15.
Figure 16.
Efficiency VOUT = 12V TAMB = 85°C
Power Dissipation VOUT = 12V TAMB = 85°C
100
3.0
95
2.5
90
85
80
VIN = 15V
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
75
70
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
VIN = 15V
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
2.0
1.5
1.0
0.5
0.0
0.0
2.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 17.
Figure 18.
Efficiency VOUT = 15V TAMB = 85°C
Power Dissipation VOUT = 15V TAMB = 85°C
100
3.0
95
2.5
90
85
80
75
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
0.0
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
2.0
1.5
1.0
0.5
0.0
70
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 19.
8
VIN = 8V
VIN = 12V
VIN = 24V
VIN = 36V
VIN = 42V
0.0
2.0
POWER DISSIPATION (W)
EFFICIENCY (%)
POWER DISSIPATION (W)
3.0
75
EFFICIENCY (%)
Power Dissipation VOUT = 5.0V TAMB = 85°C
POWER DISSIPATION (W)
EFFICIENCY (%)
Efficiency VOUT = 5.0V TAMB = 85°C
100
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 20.
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Typical Performance Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V; Cin = 10uF X7R Ceramic; CO = 47uF; TAMB = 25°C.
Power Dissipation VOUT = 18V TAMB = 85°C
3.0
95
2.5
POWER DISSIPATION (W)
EFFICIENCY (%)
Efficiency VOUT = 18V TAMB = 85°C
100
90
85
80
75
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
0.5
1.0
1.5
OUTPUT CURRENT (A)
1.0
0.5
0.0
2.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 22.
Efficiency VOUT = 24V TAMB = 85°C
Power Dissipation VOUT = 24V TAMB = 85°C
100
3.0
95
2.5
POWER DISSIPATION (W)
EFFICIENCY (%)
1.5
Figure 21.
90
85
80
75
VIN = 28V
VIN = 30V
VIN = 36V
VIN = 42V
0.0
VIN = 28V
VIN = 30V
VIN = 36V
VIN = 42V
2.0
1.5
1.0
0.5
0.0
70
0.5
1.0
1.5
OUTPUT CURRENT (A)
0.0
2.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 23.
Figure 24.
Efficiency VOUT = 30V TAMB = 85°C
Power Dissipation VOUT = 30V TAMB = 85°C
100
3.0
95
2.5
POWER DISSIPATION (W)
EFFICIENCY (%)
2.0
0.0
70
0.0
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
90
85
80
75
70
0.0
VIN = 34V
VIN = 36V
VIN = 42V
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
1.5
1.0
0.5
VIN = 34V
VIN = 36V
VIN = 42V
0.0
2.0
Figure 25.
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 26.
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Typical Performance Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V; Cin = 10uF X7R Ceramic; CO = 47uF; TAMB = 25°C.
Thermal Derating VOUT = 12V, θJA = 16°C/W
2.0
1.5
1.0
0.5
0.0
-20
Thermal Derating VOUT = 12V, θJA = 20°C/W
2.5
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
2.5
VIN = 15V
VIN = 24V
VIN = 42V
2.0
1.5
1.0
0.5
0.0
0 20 40 60 80 100 120 140
AMBIENT TEMPERATURE (°C)
-20
0 20 40 60 80 100 120 140
AMBIENT TEMPERATURE (°C)
Figure 27.
Figure 28.
Thermal Derating VOUT = 24V, θJA = 16°C/W
Thermal Derating VOUT = 24V, θJA = 20°C/W
2.0
1.5
1.0
0.5
0.0
-20
2.5
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
2.5
VIN = 30V
VIN = 36V
VIN = 42V
VIN = 30V
VIN = 36V
VIN = 42V
2.0
1.5
1.0
0.5
0.0
0 20 40 60 80 100 120 140
AMBIENT TEMPERATURE (°C)
-20
0 20 40 60 80 100 120 140
AMBIENT TEMPERATURE (°C)
Figure 29.
Figure 30.
Thermal Derating VOUT = 30V, θJA = 16°C/W
Thermal Derating VOUT = 30V, θJA = 20°C/W
2.0
1.5
1.0
0.5
0.0
-20
2.5
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
2.5
VIN = 34V
VIN = 36V
VIN = 42V
VIN = 34V
VIN = 36V
VIN = 42V
2.0
1.5
1.0
0.5
0.0
0 20 40 60 80 100 120 140
AMBIENT TEMPERATURE (°C)
Figure 31.
10
VIN = 15V
VIN = 24V
VIN = 42V
-20
0 20 40 60 80 100 120 140
AMBIENT TEMPERATURE (°C)
Figure 32.
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Typical Performance Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V; Cin = 10uF X7R Ceramic; CO = 47uF; TAMB = 25°C.
Package Thermal Resistance θJA
4 Layer Printed Circuit Board with 1oz Copper
0LFM (0m/s) air
225LFM (1.14m/s) air
500LFM (2.54m/s) air
Evaluation Board Area
35
30
25
20
15
10
5
0
0
10
20
30
40
2
BOARD AREA (cm )
50
Line and Load Regulation TAMB = 25°C
OUTPUT VOLTAGE REGULATION (%)
THERMAL RESISTANCE JA(°C/W)
40
60
0.20
0.15
0.10
0.05
0.00
-0.05
-0.10
-0.15
VIN = 15V
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
-0.20
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Figure 33.
Figure 34.
Output Ripple
VIN = 12V, IOUT = 2A, Ceramic COUT, BW = 200 MHz
Output Ripple
VIN = 24V, IOUT = 2A, Polymer Electrolytic COUT, BW = 200
MHz
VOUT=12V
1 µs/div
100 mV/div
Figure 35.
Figure 36.
Load Transient Response VIN = 24V VOUT = 12V
Load Step from 10% to 100%
Load Transient Response VIN = 24V VOUT = 12V
Load Step from 30% to 100%
VOUT=12V
100 mV/Div
1.0 A/Div
IOUT
1 ms/Div
Figure 37.
Figure 38.
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Typical Performance Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V; Cin = 10uF X7R Ceramic; CO = 47uF; TAMB = 25°C.
Current Limit
vs.
Input Voltage
VOUT = 5V TAMB = 25°C
3.5
POWER DISSIPATION (W)
DC CURRENT LIMIT LEVEL (A)
4.5
4.0
3.5
3.0
Fsw = 250kHz
Fsw = 400kHz
Fsw = 600kHz
2.5
5
10
15 20 25 30 35
INPUT VOLTAGE (V)
40
2.0
1.5
1.0
0.5
300 400 500 600 700
SWITCHING FREQUENCY (kHz)
Figure 39.
Figure 40.
Current Limit
vs.
Input Voltage
VOUT = 12V TAMB = 25°C
Switching Frequency
vs.
Power Dissipation
VOUT = 12V TAMB = 25°C
3.5
POWER DISSIPATION (W)
DC CURRENT LIMIT LEVEL (A)
2.5
200
45
4.5
4.0
3.5
3.0
Fsw = 250kHz
Fsw = 400kHz
Fsw = 600kHz
2.5
3.0
800
VIN = 15V
VIN = 24V
VIN = 36V
VIN = 42V
2.5
2.0
1.5
1.0
0.5
0.0
2.0
5
10
15 20 25 30 35
INPUT VOLTAGE (V)
40
200
45
Figure 42.
Current Limit
vs.
Input Voltage
VOUT = 24V TAMB = 25°C
Switching Frequency
vs.
Power Dissipation
VOUT = 24V TAMB = 25°C
3.5
POWER DISSIPATION (W)
4.0
3.5
3.0
Fsw = 250kHz
Fsw = 400kHz
Fsw = 600kHz
2.5
300 400 500 600 700
SWITCHING FREQUENCY (kHz)
Figure 41.
4.5
DC CURRENT LIMIT LEVEL (A)
VIN = 12V
VIN = 24V
VIN = 36V
VIN = 42V
0.0
2.0
800
3.0
2.5
2.0
1.5
VIN = 30V
VIN = 36V
VIN = 42V
1.0
0.5
0.0
2.0
30
33
36
39
42
INPUT VOLTAGE (V)
45
Figure 43.
12
3.0
Switching Frequency
vs.
Power Dissipation
VOUT = 5V TAMB = 25°C
200
300 400 500 600 700
SWITCHING FREQUENCY (kHz)
800
Figure 44.
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Typical Performance Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V; Cin = 10uF X7R Ceramic; CO = 47uF; TAMB = 25°C.
Startup
VIN = 24V IOUT = 2A
Radiated EMI of Evaluation Board, VOUT = 12V
RADIATED EMISSIONS (dB V/m)
80
VOUT
ENABLE
Emissions (Evaluation Board)
EN 55022 Limit (Class B)
70
60
50
40
30
20
10
0
0
1 ms/Div
5V/Div
200
400
600
800
FREQUENCY (MHz)
Figure 45.
1000
Figure 46.
Conducted EMI, VOUT = 12V
Evaluation Board BOM and 3.3µH 2x10µF LC line filter
CONDUCTED EMISSIONS (dB V)
80
70
Emissions
CISPR 22 Quasi Peak
CISPR 22 Average
60
50
40
30
20
10
0
0.1
1
10
FREQUENCY (MHz)
100
Figure 47.
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APPLICATION BLOCK DIAGRAM
Vin
RENT
3
VIN 1
EN
Linear reg
RENB
Cvcc
5
SS
CBST
Css
RON
2
VOUT 7
Timer
15 PH
VO
Co
FB
RFBT
RFBB
0.47 PF
RON
CFF
6
CIN
Regulator IC
Internal
Passives
GND
4
14
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COT CONTROL CIRCUIT OVERVIEW
Constant On Time control is based on a comparator and an on-time one shot, with the output voltage feedback
compared to an internal 0.8V reference. If the feedback voltage is below the reference, the high-side MOSFET is
turned on for a fixed on-time determined by a programming resistor RON. RON is connected to VIN such that ontime is reduced with increasing input supply voltage. Following this on-time, the high-side MOSFET remains off
for a minimum of 260 ns. If the voltage on the feedback pin falls below the reference level again the on-time
cycle is repeated. Regulation is achieved in this manner.
Design Steps for the LMZ14202H Application
The LMZ14202H is fully supported by Webench® which offers the following:
•
•
•
•
Component selection
Electrical simulation
Thermal simulation
Build-it prototype board for a reduction in design time
The following list of steps can be used to manually design the LMZ14202H application.
•
•
•
•
•
•
•
•
Select minimum operating VIN with enable divider resistors
Program VO with divider resistor selection
Program turn-on time with soft-start capacitor selection
Select CO
Select CIN
Set operating frequency with RON
Determine module dissipation
Layout PCB for required thermal performance
ENABLE DIVIDER, RENT AND RENB SELECTION
The enable input provides a precise 1.18V reference threshold to allow direct logic drive or connection to a
voltage divider from a higher enable voltage such as VIN. The enable input also incorporates 90 mV (typ) of
hysteresis resulting in a falling threshold of 1.09V. The maximum recommended voltage into the EN pin is 6.5V.
For applications where the midpoint of the enable divider exceeds 6.5V, a small zener can be added to limit this
voltage.
The function of the RENT and RENB divider shown in the Application Block Diagram is to allow the designer to
choose an input voltage below which the circuit will be disabled. This implements the feature of programmable
under voltage lockout. This is often used in battery powered systems to prevent deep discharge of the system
battery. It is also useful in system designs for sequencing of output rails or to prevent early turn-on of the supply
as the main input voltage rail rises at power-up. Applying the enable divider to the main input rail is often done in
the case of higher input voltage systems such as 24V AC/DC systems where a lower boundary of operation
should be established. In the case of sequencing supplies, the divider is connected to a rail that becomes active
earlier in the power-up cycle than the LMZ14202H output rail. The two resistors should be chosen based on the
following ratio:
RENT / RENB = (VIN-ENABLE/ 1.18V) – 1
(1)
The EN pin is internally pulled up to VIN and can be left floating for always-on operation. However, it is good
practice to use the enable divider and turn on the regulator when VIN is close to reaching its nominal value. This
will guarantee smooth startup and will prevent overloading the input supply.
OUTPUT VOLTAGE SELECTION
Output voltage is determined by a divider of two resistors connected between VO and ground. The midpoint of
the divider is connected to the FB input. The voltage at FB is compared to a 0.8V internal reference. In normal
operation an on-time cycle is initiated when the voltage on the FB pin falls below 0.8V. The high-side MOSFET
on-time cycle causes the output voltage to rise and the voltage at the FB to exceed 0.8V. As long as the voltage
at FB is above 0.8V, on-time cycles will not occur.
The regulated output voltage determined by the external divider resistors RFBT and RFBB is:
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VO = 0.8V x (1 + RFBT / RFBB)
(2)
Rearranging terms; the ratio of the feedback resistors for a desired output voltage is:
RFBT / RFBB = (VO / 0.8V) - 1
(3)
These resistors should be chosen from values in the range of 1 kΩ to 50 kΩ.
A feed-forward capacitor is placed in parallel with RFBT to improve load step transient response. Its value is
usually determined experimentally by load stepping between DCM and CCM conduction modes and adjusting for
best transient response and minimum output ripple.
A table of values for RFBT , RFBB , and RON is included in the simplified applications schematic.
SOFT-START CAPACITOR, CSS, SELECTION
Programmable soft-start permits the regulator to slowly ramp to its steady state operating point after being
enabled, thereby reducing current inrush from the input supply and slowing the output voltage rise-time to
prevent overshoot.
Upon turn-on, after all UVLO conditions have been passed, an internal 8uA current source begins charging the
external soft-start capacitor. The soft-start time duration to reach steady state operation is given by the formula:
tSS = VREF x CSS / Iss = 0.8V x CSS / 8uA
(4)
This equation can be rearranged as follows:
CSS = tSS x 8 μA / 0.8V
(5)
Use of a 4700pF capacitor results in 0.5ms soft-start duration. This is a recommended value. Note that high
values of CSS capacitance will cause more output voltage droop when a load transient goes across the DCMCCM boundary. Use Equation 18 below to find the DCM-CCM boundary load current for the specific operating
condition. If a fast load transient response is desired for steps between DCM and CCM mode the softstart
capacitor value should be less than 0.018µF.
As the soft-start input exceeds 0.8V the output of the power stage will be in regulation. Note that the following
conditions will reset the soft-start capacitor by discharging the SS input to ground with an internal 200 μA current
sink:
•
•
•
•
The enable input being “pulled low”
Thermal shutdown condition
Over-current fault
Internal VINUVLO
OUTPUT CAPACITOR, CO, SELECTION
None of the required output capacitance is contained within the module. At a minimum, the output capacitor must
meet the worst case RMS current rating of 0.5 x ILR P-P, as calculated in Equation 19. Beyond that, additional
capacitance will reduce output ripple so long as the ESR is low enough to permit it. A minimum value of 10 μF is
generally required. Experimentation will be required if attempting to operate with a minimum value. Low ESR
capacitors, such as ceramic and polymer electrolytic capacitors are recommended.
CAPACITANCE:
Equation 6 provides a good first pass approximation of CO for load transient requirements:
CO≥ISTEP x VFB x L x VIN/ (4 x VO x (VIN — VO) x VOUT-TRAN)
(6)
As an example, for 2A load step, VIN = 24V, VOUT = 12V, VOUT-TRAN = 50mV:
CO≥ 2A x 0.8V x 15μH x 24V / (4 x 12V x ( 24V — 12V) x 50mV)
CO≥ 20μF
ESR:
16
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The ESR of the output capacitor affects the output voltage ripple. High ESR will result in larger VOUT peak-topeak ripple voltage. Furthermore, high output voltage ripple caused by excessive ESR can trigger the overvoltage protection monitored at the FB pin. The ESR should be chosen to satisfy the maximum desired VOUT
peak-to-peak ripple voltage and to avoid over-voltage protection during normal operation. The following
equations can be used:
ESRMAX-RIPPLE ≤ VOUT-RIPPLE / ILR P-P
where
• ILR P-P is calculated using Equation 19 below
ESRMAX-OVP < (VFB-OVP - VFB) / (ILR P-P x AFB )
(7)
where
•
AFB is the gain of the feedback network from VOUT to VFB at the switching frequency.
(8)
As worst case, assume the gain of AFB with the CFF capacitor at the switching frequency is 1.
The selected capacitor should have sufficient voltage and RMS current rating. The RMS current through the
output capacitor is:
I(COUT(RMS)) = ILR P-P / √12
(9)
INPUT CAPACITOR, CIN, SELECTION
The LMZ14202H module contains an internal 0.47 µF input ceramic capacitor. Additional input capacitance is
required external to the module to handle the input ripple current of the application. This input capacitance should
be located as close as possible to the module. Input capacitor selection is generally directed to satisfy the input
ripple current requirements rather than by capacitance value. Worst case input ripple current rating is dictated by
Equation 10:
I(CIN(RMS)) ≊ 1 / 2 x IO x √ (D / 1-D)
where
•
D ≊ VO / VIN
(10)
(As a point of reference, the worst case ripple current will occur when the module is presented with full load
current and when VIN = 2 x VO).
Recommended minimum input capacitance is 10uF X7R ceramic with a voltage rating at least 25% higher than
the maximum applied input voltage for the application. It is also recommended that attention be paid to the
voltage and temperature deratings of the capacitor selected. It should be noted that ripple current rating of
ceramic capacitors may be missing from the capacitor data sheet and you may have to contact the capacitor
manufacturer for this rating.
If the system design requires a certain maximum value of input ripple voltage ΔVIN to be maintained then
Equation 11 may be used.
CIN ≥ IO x D x (1–D) / fSW-CCM x ΔVIN
(11)
If ΔVIN is 1% of VIN for a 24V input to 12V output application this equals 240 mV and fSW = 400 kHz.
CIN≥ 2A x 12V/24V x (1– 12V/24V) / (400000 x 0.240 V)
CIN≥ 5.2μF
Additional bulk capacitance with higher ESR may be required to damp any resonant effects of the input
capacitance and parasitic inductance of the incoming supply lines.
ON TIME, RON, RESISTOR SELECTION
Many designs will begin with a desired switching frequency in mind. As seen in the Typical Performance
Characteristics section, the best efficiency is achieved in the 300kHz-400kHz switching frequency range.
Equation 12 can be used to calculate the RON value.
fSW(CCM) ≊ VO / (1.3 x 10-10 x RON)
(12)
This can be rearranged as
RON ≊ VO / (1.3 x 10 -10 x fSW(CCM)
(13)
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The selection of RON and fSW(CCM) must be confined by limitations in the on-time and off-time for the COT Control
Circuit Overview section.
The on-time of the LMZ14202H timer is determined by the resistor RON and the input voltage VIN. It is calculated
as follows:
tON = (1.3 x 10-10 x RON) / VIN
(14)
The inverse relationship of tON and VIN gives a nearly constant switching frequency as VIN is varied. RON should
be selected such that the on-time at maximum VIN is greater than 150 ns. The on-timer has a limiter to ensure a
minimum of 150 ns for tON. This limits the maximum operating frequency, which is governed by Equation 15:
fSW(MAX) = VO / (VIN(MAX) x 150 nsec)
(15)
This equation can be used to select RON if a certain operating frequency is desired so long as the minimum ontime of 150 ns is observed. The limit for RON can be calculated as follows:
RON ≥ VIN(MAX) x 150 nsec / (1.3 x 10 -10)
(16)
If RON calculated in Equation 13 is less than the minimum value determined in Equation 16 a lower frequency
should be selected. Alternatively, VIN(MAX) can also be limited in order to keep the frequency unchanged.
Additionally, the minimum off-time of 260 ns (typ) limits the maximum duty ratio. Larger RON (lower FSW) should
be selected in any application requiring large duty ratio.
Discontinuous Conduction and Continuous Conduction Modes
At light load the regulator will operate in discontinuous conduction mode (DCM). With load currents above the
critical conduction point, it will operate in continuous conduction mode (CCM). When operating in DCM the
switching cycle begins at zero amps inductor current; increases up to a peak value, and then recedes back to
zero before the end of the off-time. Note that during the period of time that inductor current is zero, all load
current is supplied by the output capacitor. The next on-time period starts when the voltage on the FB pin falls
below the internal reference. The switching frequency is lower in DCM and varies more with load current as
compared to CCM. Conversion efficiency in DCM is maintained since conduction and switching losses are
reduced with the smaller load and lower switching frequency. Operating frequency in DCM can be calculated as
follows:
fSW(DCM)≊VO x (VIN-1) x 15μH x 1.18 x 1020 x IO / (VIN–VO) x RON2
(17)
In CCM, current flows through the inductor through the entire switching cycle and never falls to zero during the
off-time. The switching frequency remains relatively constant with load current and line voltage variations. The
CCM operating frequency can be calculated using Equation 12 above.
The approximate formula for determining the DCM/CCM boundary is as follows:
IDCB≊VOx (VIN–VO) / ( 2 x 15μH x fSW(CCM) x VIN)
(18)
The inductor internal to the module is 15μH. This value was chosen as a good balance between low and high
input voltage applications. The main parameter affected by the inductor is the amplitude of the inductor ripple
current (ILR). ILR can be calculated with:
ILR P-P=VO x (VIN- VO) / (15µH x fSW x VIN)
where
•
VIN is the maximum input voltage and fSW is determined from Equation 12.
(19)
If the output current IO is determined by assuming that IO = IL, the higher and lower peak of ILR can be
determined. Be aware that the lower peak of ILR must be positive if CCM operation is required.
POWER DISSIPATION AND BOARD THERMAL REQUIREMENTS
For a design case of VIN = 24V, VOUT = 12V, IOUT = 2A, TAMB (MAX) = 85°C , and TJUNCTION = 125°C, the device
must see a maximum junction-to-ambient thermal resistance of:
θJA-MAX < (TJ-MAX - TAMB(MAX)) / PD
This θJA-MAX will ensure that the junction temperature of the regulator does not exceed TJ-MAX in the particular
application ambient temperature.
18
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To calculate the required θJA-MAX we need to get an estimate for the power losses in the IC. The following graph
is taken form the Typical Performance Characteristics section and shows the power dissipation of the
LMZ14202H for VOUT = 12V at 85°C TAMB.
Figure 48. Power Dissipation VOUT = 12V TAMB = 85°C
POWER DISSIPATION (W)
3.0
VIN = 15V
VIN = 24V
VIN = 30V
VIN = 36V
VIN = 42V
2.5
2.0
1.5
1.0
0.5
0.0
0.0
0.5
1.0
1.5
OUTPUT CURRENT (A)
2.0
Using the 85°C TAMB power dissipation data PD for VIN = 24V and VOUT = 12V is estimated to be 1.8W. The
necessary θJA-MAX can now be calculated.
θJA-MAX < (125°C - 85°C) / 1.8W
θJA-MAX < 22.2°C/W
To achieve this thermal resistance the PCB is required to dissipate the heat effectively. The area of the PCB will
have a direct effect on the overall junction-to-ambient thermal resistance. In order to estimate the necessary
copper area we can refer to the following Package Thermal Resistance graph. This graph is taken from the
Typical Performance Characteristics section and shows how the θJA varies with the PCB area.
Figure 49. Package Thermal Resistance θJA 4 Layer Printed Circuit Board with 1oz Copper
THERMAL RESISTANCE JA(°C/W)
40
0LFM (0m/s) air
225LFM (1.14m/s) air
500LFM (2.54m/s) air
Evaluation Board Area
35
30
25
20
15
10
5
0
0
10
20
30
40
2
BOARD AREA (cm )
50
60
For θJA-MAX< 22.2°C/W and only natural convection (i.e. no air flow), the PCB area will have to be at least 30cm2.
This corresponds to a square board with approximately 5.5cm x 5.5cm (2.17in x 2.17in) copper area, 4 layers,
and 1oz copper thickness. Higher copper thickness will further improve the overall thermal performance. Note
that thermal vias should be placed under the IC package to easily transfer heat from the top layer of the PCB to
the inner layers and the bottom layer.
For more guidelines and insight on PCB copper area, thermal vias placement, and general thermal design
practices please refer to Application Note AN-2020 (http://www.ti.com/lit/an/snva419b/snva419b.pdf).
PC BOARD LAYOUT GUIDELINES
PC board layout is an important part of DC-DC converter design. Poor board layout can disrupt the performance
of a DC-DC converter and surrounding circuitry by contributing to EMI, ground bounce and resistive voltage drop
in the traces. These can send erroneous signals to the DC-DC converter resulting in poor regulation or instability.
Good layout can be implemented by following a few simple design rules.
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VIN
LMZ14202H
VIN
VO
VOUT
High
di/dt
Cin1
CO1
GND
Loop 2
Loop 1
1. Minimize area of switched current loops.
From an EMI reduction standpoint, it is imperative to minimize the high di/dt paths during PC board layout. The
high current loops that do not overlap have high di/dt content that will cause observable high frequency noise on
the output pin if the input capacitor (Cin1) is placed at a distance away from the LMZ14202H. Therefore place
CIN1 as close as possible to the LMZ14202H VIN and GND exposed pad. This will minimize the high di/dt area
and reduce radiated EMI. Additionally, grounding for both the input and output capacitor should consist of a
localized top side plane that connects to the GND exposed pad (EP).
2. Have a single point ground.
The ground connections for the feedback, soft-start, and enable components should be routed to the GND pin of
the device. This prevents any switched or load currents from flowing in the analog ground traces. If not properly
handled, poor grounding can result in degraded load regulation or erratic output voltage ripple behavior. Provide
the single point ground connection from pin 4 to EP.
3. Minimize trace length to the FB pin.
Both feedback resistors, RFBT and RFBB, and the feed forward capacitor CFF, should be located close to the FB
pin. Since the FB node is high impedance, maintain the copper area as small as possible. The traces from RFBT,
RFBB, and CFF should be routed away from the body of the LMZ14202H to minimize noise pickup.
4. Make input and output bus connections as wide as possible.
This reduces any voltage drops on the input or output of the converter and maximizes efficiency. To optimize
voltage accuracy at the load, ensure that a separate feedback voltage sense trace is made to the load. Doing so
will correct for voltage drops and provide optimum output accuracy.
5. Provide adequate device heat-sinking.
Use an array of heat-sinking vias to connect the exposed pad to the ground plane on the bottom PCB layer. If
the PCB has a plurality of copper layers, these thermal vias can also be employed to make connection to inner
layer heat-spreading ground planes. For best results use a 6 x 6 via array with minimum via diameter of 10mils
(254 μm) thermal vias spaced 59mils (1.5 mm). Ensure enough copper area is used for heat-sinking to keep the
junction temperature below 125°C.
Additional Features
OUTPUT OVER-VOLTAGE COMPARATOR
The voltage at FB is compared to a 0.92V internal reference. If FB rises above 0.92V the on-time is immediately
terminated. This condition is known as over-voltage protection (OVP). It can occur if the input voltage is
increased very suddenly or if the output load is decreased very suddenly. Once OVP is activated, the top
MOSFET on-times will be inhibited until the condition clears. Additionally, the synchronous MOSFET will remain
on until inductor current falls to zero.
20
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CURRENT LIMIT
Current limit detection is carried out during the off-time by monitoring the current in the synchronous MOSFET.
Referring to the Functional Block Diagram, when the top MOSFET is turned off, the inductor current flows
through the load, the PGND pin and the internal synchronous MOSFET. If this current exceeds ICL the current
limit comparator disables the start of the next on-time period. The next switching cycle will occur only if the FB
input is less than 0.8V and the inductor current has decreased below ICL. Inductor current is monitored during the
period of time the synchronous MOSFET is conducting. So long as inductor current exceeds ICL, further on-time
intervals for the top MOSFET will not occur. Switching frequency is lower during current limit due to the longer
off-time. It should also be noted that DC current limit varies with duty cycle, switching frequency, and
temperature.
THERMAL PROTECTION
The junction temperature of the LMZ14202H should not be allowed to exceed its maximum ratings. Thermal
protection is implemented by an internal Thermal Shutdown circuit which activates at 165 °C (typ) causing the
device to enter a low power standby state. In this state the main MOSFET remains off causing VO to fall, and
additionally the CSS capacitor is discharged to ground. Thermal protection helps prevent catastrophic failures for
accidental device overheating. When the junction temperature falls back below 145 °C (typ Hyst = 20 °C) the SS
pin is released, VO rises smoothly, and normal operation resumes.
ZERO COIL CURRENT DETECTION
The current of the lower (synchronous) MOSFET is monitored by a zero coil current detection circuit which
inhibits the synchronous MOSFET when its current reaches zero until the next on-time. This circuit enables the
DCM operating mode, which improves efficiency at light loads.
PRE-BIASED STARTUP
The LMZ14202H will properly start up into a pre-biased output. This is startup situation is common in multiple rail
logic applications where current paths may exist between different power rails during the startup sequence. The
pre-bias level of the output voltage must be less than the input UVLO set point. This will prevent the output prebias from enabling the regulator through the high side MOSFET body diode.
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Copyright © 2011–2013, Texas Instruments Incorporated
Product Folder Links: LMZ14202H
21
LMZ14202H
SNVS691D – JANUARY 2011 – REVISED FEBRUARY 2013
www.ti.com
REVISION HISTORY
Changes from Revision C (February 2013) to Revision D
•
22
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 21
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Copyright © 2011–2013, Texas Instruments Incorporated
Product Folder Links: LMZ14202H
PACKAGE OPTION ADDENDUM
www.ti.com
29-May-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
LMZ14202HTZ/NOPB
ACTIVE
PFM
NDW
7
250
Green (RoHS
& no Sb/Br)
CU SN
Level-3-245C-168 HR
-40 to 125
LMZ14202
HTZ
LMZ14202HTZE/NOPB
ACTIVE
PFM
NDW
7
45
Green (RoHS
& no Sb/Br)
CU SN
Level-3-245C-168 HR
-40 to 125
LMZ14202
HTZ
LMZ14202HTZX/NOPB
ACTIVE
PFM
NDW
7
500
Green (RoHS
& no Sb/Br)
CU SN
Level-3-245C-168 HR
-40 to 125
LMZ14202
HTZ
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
29-May-2013
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
26-Mar-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
LMZ14202HTZ/NOPB
PFM
NDW
7
250
330.0
24.4
10.6
14.22
5.0
16.0
24.0
Q2
LMZ14202HTZX/NOPB
PFM
NDW
7
500
330.0
24.4
10.6
14.22
5.0
16.0
24.0
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
26-Mar-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LMZ14202HTZ/NOPB
PFM
NDW
7
250
367.0
367.0
45.0
LMZ14202HTZX/NOPB
PFM
NDW
7
500
367.0
367.0
45.0
Pack Materials-Page 2
MECHANICAL DATA
NDW0007A
BOTTOM SIDE OF PACKAGE
TOP SIDE OF PACKAGE
TZA07A (Rev D)
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