LMZ10501 1A SIMPLE SWITCHER® Nano

Sample &
Buy
Product
Folder
Support &
Community
Tools &
Software
Technical
Documents
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
LMZ10501 1-A SIMPLE SWITCHER® Nano Module With 5.5-V Maximum Input Voltage
1 Features
2 Applications
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
1
•
•
•
•
•
Output Current Up to 1 A
Input Voltage Range 2.7 V to 5.5 V
Output Voltage Range 0.6 V to 3.6 V
Efficiency up to 95%
Integrated Inductor
8-Pin LLP Footprint
–40°C to 125°C Junction Temperature Range
Adjustable Output Voltage
2.0-MHz Fixed PWM Switching Frequency
Integrated Compensation
Soft-Start Function
Current Limit Protection
Thermal Shutdown Protection
Input Voltage UVLO for Power-Up, Power-Down,
and Brown-Out Conditions
Only 5 External Components — Resistor Divider
and 3 Ceramic Capacitors
Small Solution Size
Low Output Voltage Ripple
Easy Component Selection and Simple PCB
Layout
High Efficiency Reduces System Heat Generation
•
•
•
Point of Load Conversions From 3.3-V and 5-V
Rails
Space Constrained Applications
Low Output Noise Applications
Quick Links to Reference Designs:
VOUT = 1.2 V, VOUT = 1.8 V,
VOUT = 2.5 V, VOUT = 3.3 V
3 Description
The LMZ10501 SIMPLE SWITCHER® nano module
is an easy-to-use step-down DC-DC solution capable
of driving up to 1-A load in space-constrained
applications. Only an input capacitor, an output
capacitor, a small VCON filter capacitor, and two
resistors are required for basic operation. The nano
module comes in an 8-pin LLP footprint package with
an inductor. Internal current limit based soft-start
function, current overload protection, and thermal
shutdown are also provided.
Device Information(1)
PART NUMBER
LMZ10501
Typical Efficiency at VIN = 3.6 V
Radiated EMI (CISPR22)
VIN = 5.0 V, VOUT = 1.8 V, IOUT = 1A
80
80
70
70
60
50
VOUT=1.2V
VOUT=1.8V
VOUT=2.5V
VOUT=3.3V
20
0.0
0.2
0.4
0.6
LOAD CURRENT (A)
0.8
1.0
C001
Radiated Emissions (dBµV/m)
EFFICIENCY (%)
90
30
BODY SIZE (NOM)
3.00 mm x 2.60 mm
(1) For all available packages, see the orderable addendum at
the end of the datasheet.
100
40
PACKAGE
SIL (8)
Evaluation Board
EN 55022 Class B Limit
EN 55022 Class A Limit
60
50
40
30
20
10
0
0
200
400
600
Frequency (MHz)
800
1000
C001
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
6.6
6.7
4
4
4
4
5
5
7
Absolute Maximum Ratings ......................................
Handling Ratings ......................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
System Characteristics .............................................
Typical Characteristics ..............................................
Detailed Description .............................................. 9
7.1
7.2
7.3
7.4
Overview ................................................................... 9
Functional Block Diagram ......................................... 9
Feature Description................................................... 9
Device Functional Modes........................................ 11
8
Application and Implementation ........................ 13
8.1 Application Information............................................ 13
8.2 Typical Application ................................................. 13
9
Power Supply Recommendations...................... 20
9.1 Voltage Range ........................................................ 20
9.2 Current Capability ................................................... 20
9.3 Input Connection .................................................... 20
10 Layout................................................................... 21
10.1 Layout Guidelines ................................................. 21
10.2 Layout Example .................................................... 21
10.3 Package Considerations ....................................... 22
11 Device and Documentation Support ................. 23
11.1
11.2
11.3
11.4
Documentation Support ........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
23
23
23
23
12 Mechanical, Packaging, and Orderable
Information ........................................................... 23
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision E (January 2014) to Revision F
•
Added Pin Configuration and Functions section, Handling Rating table, Feature Description section, Device
Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout
section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information
section ................................................................................................................................................................................... 1
Changes from Revision D (March 2013) to Revision E
•
2
Page
Page
Added new package SIL0008A ............................................................................................................................................. 3
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
5 Pin Configuration and Functions
8-Pin
SIL Package
SIDE VIEW
TOP VIEW
BOTTOM VIEW
1
8
8
VREF
2
7
7
VIN
3
6
6
PGND
4
5
5
VOUT
PAD
(SGND)
EN
1
VCON
2
FB
3
SGND
4
Pin Functions
PIN
NAME
NO.
I/O
DESCRIPTION
EN
1
I
Enable Input. Set this digital input higher than 1.2V for normal operation. For shutdown, set
low. Pin is internally pulled up to VIN and can be left floating for always-on operation.
VCON
2
I
Output voltage control pin. Connect to analog voltage from resisitve divider or DAC/controller
to set the VOUT voltage. VOUT = 2.5 x VCON. Connect a small (470pF) capacitor from this pin
to SGND to provide noise filtering.
FB
3
I
Feedback of the error amplifier. Connect directly to output capacitor to sense VOUT.
SGND
4
I
Ground for analog and control circuitry. Connect to PGND at a single point.
VOUT
5
O
Output Voltage. Connected to one terminal of the integrated inductor. Connect output filter
capacitor between VOUT and PGND.
PGND
6
I
Power ground for the power MOSFETs and gate-drive circuitry.
VIN
7
I
Voltage supply input. Connect ceramic capacitor between VIN and PGND as close as
possible to these two pins. Typical capacitor values are between 4.7µF and 22µF.
VREF
8
O
2.35-V voltage reference output. Typically connected to VCON pin through a resistive divider
to set the output voltage.
I
The center pad underneath the SIL0008A package is internally tied to SGND. This pad
should be connected to the ground plane for improved thermal performance.
PAD
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
3
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)
(1) (2) (3)
VIN, VREF to SGND
MIN
MAX
UNIT
−0.2
+6.0
V
PGND to SGND
−0.2
+0.2
V
EN, FB, VCON
(SGND
−0.2)
(VIN +0.2)
w/6.0 max
V
VOUT
(PGND
−0.2)
(VIN +0.2)
w/6.0 max
V
−40
125
°C
260
°C
Junction Temperature (TJ-MAX)
Maximum Lead Temperature
(1)
(2)
(3)
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
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 the Electrical Characteristics table for specifications and test conditions.
6.2 Handling Ratings
Tstg
Storage temperature range
V(ESD)
(1)
(2)
Electrostatic discharge
MIN
MAX
UNIT
−65
150
°C
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all
pins (1)
1000
Charged device model (CDM), per JEDEC specification
JESD22-C101, all pins (2)
250
V
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
Input Voltage Range
Recommended Load Current
Junction Temperature (TJ) Range
MIN
MAX
2.7
5.5
UNIT
0
1000
mA
−40
125
°C
V
6.4 Thermal Information
LMZ10501
THERMAL METRIC
(1)
SIL
UNIT
8 PINS
(2)
RθJA
Junction-to-ambient thermal resistance
RθJC(top)
Junction-to-case (top) thermal resistance
25
RθJB
Junction-to-board thermal resistance
9.2
ψJT
Junction-to-top characterization parameter
1.5
ψJB
Junction-to-board characterization parameter
9.1
RθJC(bot)
Junction-to-case (bottom) thermal resistance
25
(1)
(2)
4
SIL0008A Package
45.8
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
Junction-to-ambient thermal resistance (θJA) is based on 4 layer board thermal measurements, performed under the conditions and
guidelines set forth in the JEDEC standards JESD51-1 to JESD51-11. θJA varies with PCB copper area, power dissipation, and airflow.
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
6.5 Electrical Characteristics
over operating free-air temperature range (unless otherwise noted). 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 = 3.6
V, VEN = 1.2 V. (1)
PARAMETER
TEST CONDITIONS
MIN (1)
TYP (2)
MAX (1)
UNIT
5.875
5.9925
V
V/V
SYSTEM PARAMETERS
VREF x GAIN
Reference voltage x VCON to
FB Gain
VIN = VEN = 5.5V, VCON =
1.44V
5.7575
GAIN
VCON to FB Gain
VIN = 5.5V, VCON = 1.44V
2.4375
2.5
2.5750
VINUVLO
VIN rising threshold
2.24
2.41
2.64
V
VINUVLO
VIN UVLO hysteresis
120
165
200
mV
HYST
ISHDN
Shutdown supply current
VIN = 3.6V, VEN = 0.5V (3)
11
18
µA
Iq
DC bias current into VIN
VIN = 5.5V, VCON = 1.6V,
IOUT = 0A
6.5
9.5
mA
RDROPOUT
VIN to VOUTresistance
IOUT = 200 mA
305
575
mΩ
I LIM
DC Output Current Limit
VCON = 1.72V
FOSC
2.25
MHz
(4)
1025
1350
Internal oscillator frequency
1.75
2.0
VIH,ENABLE
Enable logic HIGH voltage
1.2
VIL,ENABLE
Enable logic LOW voltage
TSD
Thermal shutdown
TSD-HYST
Thermal shutdown hysteresis
DMAX
Maximum duty cycle
TON-MIN
Minimum on-time
θJA
SIL0008A Package Thermal
Resistance
(1)
(2)
(3)
(4)
mA
V
0.5
Rising Threshold
V
150
°C
20
°C
100%
50
ns
20mm x 20mm board
2 layers, 2 oz copper, 0.5W,
no airlow
77
°C/W
15mm x 15mm board
2 layers, 2 oz copper, 0.5W,
no airlow
88
10mm x 10mm board
2 layers, 2 oz copper, 0.5W,
no airlow
107
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 the Average Outgoing Quality Level (AOQL).
Typical numbers are at 25°C and represent the most likely parametric norm.
Shutdown current includes leakage current of the high side PFET.
Current limit is built-in, fixed, and not adjustable.
6.6 System Characteristics
The following specifications are ensured by design providing the component values in Figure 12 are used (CIN = COUT = 10
µF, 6.3 V, 0603, TDK C1608X5R0J106K). These parameters are not ensured by production testing. Unless otherwise
stated the following conditions apply: TA = 25°C.
PARAMETER
ΔVOUT/VO
UT
ΔVOUT/VO
UT
ΔVOUT/VO
UT
VREF
TRISE
TEST CONDITIONS
MIN
TYP
Output Voltage Regulation Over Line VOUT = 0.6 V
Voltage and Load Current
ΔVIN = 2.7 V to 4.2 V
ΔIOUT = 0A to 1A
±1.75%
Output Voltage Regulation Over Line VOUT = 1.5 V
Voltage and Load Current
ΔVIN = 2.7 V to 5.5 V
ΔIOUT = 0A to 1A
±0.92%
Output Voltage Regulation Over Line VOUT = 3.6 V
Voltage and Load Current
ΔVIN = 4.0 V to 5.5 V
ΔIOUT = 0A to 1A
±0.38%
Rise time of reference voltage
EN = Low to High, VIN = 4.2 V
VOUT = 2.7 V, IOUT = 1A
MAX
UNIT
10
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
µs
5
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
System Characteristics (continued)
The following specifications are ensured by design providing the component values in Figure 12 are used (CIN = COUT = 10
µF, 6.3 V, 0603, TDK C1608X5R0J106K). These parameters are not ensured by production testing. Unless otherwise
stated the following conditions apply: TA = 25°C.
PARAMETER
η
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Peak Efficiency
VIN = 5.0 V, VOUT = 3.3 V
IOUT = 200 mA
95%
Full Load Efficiency
VIN = 5.0 V, VOUT = 3.6 V
IOUT = 1000 mA
91%
VOUT
Ripple
Output voltage ripple
VIN = 5.0 V, VOUT = 1.8 V
IOUT = 1000 mA
10
mV pk-pk
Line
Transient
Line transient response
VIN = 2.7 V to 5.5 V,
TR = TF= 10 µs,
VOUT = 1.8 V, IOUT = 1000 mA
30
mV pk-pk
Load
Transient
Load transient response
VIN = 5.0 V
TR = TF = 40 µs,
VOUT = 1.8 V
IOUT = 100 mA to 1000 mA
30
mV pk-pk
6
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
6.7 Typical Characteristics
Unless otherwise specified the following conditions apply: VIN = 3.6 V, TA = 25°C
1.2
1.0
0.40
OUTPUT CURRENT (A)
DROPOUT VOLTAGE (V)
0.50
0.30
0.20
VIN=2.7V
VIN=3V
VIN=3.3V
VIN=3.6V
0.10
0.00
0.0
0.2
0.4
0.6
0.8
0.6
0.4
0.0
60
1.0
OUTPUT CURRENT (A)
1.0
0.8
0.6
0.4
VIN=3.3V
VIN=3.6V
VIN=5V
VIN=5.5V
70
100
110
120
AMBIENT TEMPERATURE (ƒC)
130
60
0.6
0.4
VIN=4V
VIN=4.5V
VIN=5V
VIN=5.5V
0.2
0.0
60
70
C001
80
90
100
110
120
130
AMBIENT TEMPERATURE (ƒC)
C003
Figure 4. Thermal Derating VOUT = 2.5 V, ΘJA = 77°C/W
Radiated Emissions (dBµV/m)
OUTPUT CURRENT (A)
70
80
0.8
130
VIN=3.3V
VIN=3.6V
VIN=5V
VIN=5.5V
1.2
1.0
120
0.4
C002
Figure 3. Thermal Derating VOUT = 1.8 V, ΘJA = 77°C/W
110
0.6
0.0
90
100
0.8
0.2
80
90
Figure 2. Thermal Derating VOUT = 1.2 V, ΘJA = 77°C/W
1.2
60
80
AMBIENT TEMPERATURE (ƒC)
1.2
0.0
70
C001
Figure 1. Dropout Voltage vs Load Current and Input
Voltage, TA = 85°C
0.2
VIN=3.3V
VIN=3.6V
VIN=5V
VIN=5.5V
0.2
1.0
LOAD CURRENT (A)
OUTPUT CURRENT (A)
0.8
Evaluation Board
EN 55022 Class B Limit
EN 55022 Class A Limit
70
60
50
40
30
20
10
0
80
90
100
110
AMBIENT TEMPERATURE (ƒC)
120
0
130
Figure 5. Thermal Derating VOUT = 3.3 V, ΘJA = 77°C/W
200
400
600
Frequency (MHz)
C004
800
1000
C001
Figure 6. Radiated EMI (Cispr22) VIN = 5.0 V, VOUT = 1.8 V,
IOUT = 1-A Default Evaluation Board BOM
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
7
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
Typical Characteristics (continued)
Unless otherwise specified the following conditions apply: VIN = 3.6 V, TA = 25°C
100
Radiated Emissions (dBµV/m)
VCON
Peak Emissions
Quasi Peak Limit
Average Limit
90
80
500 mV/Div
70
60
50
300 mA/Div
IL
40
300 mA/Div
30
20
10
IOUT
500 mV/Div
VOUT
10 µs/Div
0
0.1
1
10
Frequency (MHz)
100
C001
Figure 7. Conducted EMI VIN = 5.0 V, VOUT = 1.8 V, IOUT = 1-A
Default Evaluation Board BOM with Additional 2.2-µh 1-µf
LC Input Filter
8
Submit Documentation Feedback
Figure 8. Startup
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
7 Detailed Description
7.1 Overview
The LMZ10501 SIMPLE SWITCHER® nano module is an easy-to-use step-down DC-DC solution capable of
driving up to 1A load in space-constrained applications. Only an input capacitor, an output capacitor, a small
VCON filter capacitor, and two resistors are required for basic operation. The nano module comes in 8-pin LLP
footprint package with an integrated inductor. The LMZ10501 operates in fixed 2.0MHz PWM (Pulse Width
Modulation) mode, and is designed to deliver power at maximum efficiency. The output voltage is typically set by
using a resistive divider between the built-in reference voltage VREF and the control pin VCON. The VCON pin is the
positive input to the error amplifier. The output voltage of the LMZ10501 can also be dynamically adjusted
between 0.6V and 3.6V by driving the VCON pin externally. Internal current limit based softstart function, current
overload protection, and thermal shutdown are also provided.
7.2 Functional Block Diagram
VREF
VIN
UVLO
REFERENCE
VOLTAGE
VCON
ERROR
AMPLIFIER
FB
COMP
CURRENT
COMP
CURRENT SENSE
L
VOUT
MOSFET
CONTROL
LOGIC
Integrated
Inductor
VIN
UVLO
EN
MAIN CONTROL
TSD
OSCILLATOR
SGND
PGND
7.3 Feature Description
7.3.1 Current Limit
The LMZ10501 current limit feature protects the module during an overload condition. The circuit employs
positive peak current limit in the PFET and negative peak current limit in the NFET switch. The positive peak
current through the PFET is limited to 1.7A (typ.). When the current reaches this limit threshold the PFET switch
is immediately turned off until the next switching cycle. This behavior continues on a cycle-by-cycle basis until the
overload condition is removed from the output. The typical negative peak current limit through the NFET switch is
-0.6A (typ.).
The ripple of the inductor current depends on the input and output voltages. This means that the DC level of the
output current when the peak current limiting occurs will also vary over the line voltage and the output voltage
level. Refer to the DC Output Current Limit plots in the Typical Characteristics section for more information.
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
9
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
Feature Description (continued)
7.3.2 Startup Behavior and Softstart
The LMZ10501 features a current limit based soft start circuit in order to prevent large in-rush current and output
overshoot as VOUT is ramping up. This is achieved by gradually increasing the PFET current limit threshold to the
final operating value as the output voltage ramps during startup. The maximum allowed current in the inductor is
stepped up in a staircase profile for a fixed number of switching periods in each step. Additionally, the switching
frequency in the first step is set at 450kHz and is then increased for each of the following steps until it reaches
2MHz at the final step of current limiting. This current limiting behavior is illustrated in Figure 9 and allows for a
smooth VOUT ramp up.
VCON
500 mV/Div
300 mA/Div
IL
300 mA/Div
IOUT
500 mV/Div
VOUT
10 µs/Div
Figure 9. Startup Behavior of Current Limit Based Softstart.
The soft start rate is also limited by the VCON ramp up rate. The VCON pin is discharged internally through a pull
down device before startup occurs. This is done to deplete any residual charge on the VCON filter capacitor and
allow the VCON voltage to ramp up from 0V when the part is started. The events that cause VCON discharge are
thermal shutdown, UVLO, EN low, or output short circuit detection. The minimum recommended capacitance on
VCON is 220pF and the maximum is 1nF. The duration of startup current limiting sequence takes approximately
75µs. After the sequence is completed, the feedback voltage is monitored for output short circuit events.
7.3.3 Output Short Circuit Protection
In addition to cycle by cycle current limit, the LMZ10501 features a second level of short circuit protection. If the
load pulls the output voltage down and the feedback voltage falls to 0.375 V, the output short circuit protection
will engage. In this mode the internal PFET switch is turned OFF after the current limit comparator trips and the
beginning of the next cycle is inhibited for approximately 230µs. This forces the inductor current to ramp down
and limits excessive current draw from the input supply when the output of the regulator is shorted. The
synchronous rectifier is always OFF in this mode. After 230 µs of non-switching a new startup sequence is
initiated. During this new startup sequence the current limit is gradually stepped up to the nominal value as
illustrated in the Startup Behavior and Softstart section. After the startup sequence is completed again, the
feedback voltage is monitored for output short circuit. If the short circuit is still persistent after the new startup
sequence, switching will be stopped again and there will be another 230-µs off period. A persistent output short
condition results in a hiccup behavior where the LMZ10501 goes through the normal startup sequence, then
detects the output short at the end of startup, terminates switching for 230µs, and repeats this cycle until the
output short is released. This behavior is illustrated in Figure 10.
VOUT
1V/Div
IIN
100 mA/Div
IL
0.5A/Div
VCON
100 µs/Div
1V/Div
Figure 10. Hiccup Behavior with Persistent Output Short Circuit.
10
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
Feature Description (continued)
Since the output current is limited during normal startup by the softstart function, the current charging the output
capacitor is also limited. This results in a smooth VOUT ramp up to nominal voltage. However, using excessively
large output capacitance or VCON capacitance under normal conditions can prevent the output voltage from
reaching 0.375 V at the end of the startup sequence. In such cases the module will maintain the described above
hiccup mode and the output voltage will not ramp up to final value. To cause this condition, one would have to
use unnecessarily large output capacitance for 1A load applications. See the Input And Output Capacitor
Selection section for guidance on maximum capacitances for different output voltage settings.
7.3.4 Thermal Overload Protection
The junction temperature of the LMZ10501 should not be allowed to exceed its maximum operating rating of
125°C. Thermal protection is implemented by an internal thermal shutdown circuit which activates at 150°C (typ).
When this temperature is reached, the device enters a low power standby state. In this state switching remains
off causing the output voltage to fall. Also, the VCON capacitor is discharged to SGND. When the junction
temperature falls back below 130°C (typ) normal startup occurs and VOUT rises smoothly from 0V. Applications
requiring maximum output current may require derating at elevated ambient temperature. See the Typical
Characteristics section for thermal derating plots for various output voltages.
7.4 Device Functional Modes
7.4.1 Circuit Operation
The LMZ10501 is a synchronous Buck power module using a PFET for the high side switch and an NFET for the
synchronous rectifier switch. The output voltage is regulated by modulating the PFET switch on-time. The circuit
generates a duty-cycle modulated rectangular signal. The rectangular signal is averaged using a low pass filter
formed by the integrated inductor and an output capacitor. The output voltage is equal to the average of the dutycycle modulated rectangular signal. In PWM mode, the switching frequency is constant. The energy per cycle to
the load is controlled by modulating the PFET on-time, which controls the peak inductor current. In current mode
control architecture, the inductor current is compared with the slope compensated output of the error amplifier. At
the rising edge of the clock, the PFET is turned ON, ramping up the inductor current with a slope of (VIN VOUT)/L. The PFET is ON until the current signal equals the error signal. Then the PFET is turned OFF and
NFET is turned ON, ramping down the inductor current with a slope of VOUT /L. At the next rising edge of the
clock, the cycle repeats. An increase of load pulls the output voltage down, resulting in an increase of the error
signal. As the error signal goes up, the peak inductor current is increased, elevating the average inductor current
and responding to the heavier load. To ensure stability, a slope compensation ramp is subtracted from the error
signal and internal loop compensation is provided.
7.4.2 Input Under Voltage Detection
The LMZ10501 implements an under voltage lock out (UVLO) circuit to ensure proper operation during startup,
shutdown and input supply brownout conditions. The circuit monitors the voltage at the VIN pin to ensure that
sufficient voltage is present to bias the regulator. If the under voltage threshold is not met, all functions of the
controller are disabled and the controller remains in a low power standby state.
7.4.3 Shutdown Mode
To shutdown the LMZ10501, pull the EN pin low (< 0.5 V). In the shutdown mode all internal circuits are turned
OFF.
7.4.4 EN Pin Operation
The EN pin is internally pulled up to VIN through a 790kΩ (typ.) resistor. This allows the nano module to be
enabled by default when the EN pin is left floating. In such cases VIN will set EN high when VIN reaches 1.2 V. As
the input voltage continues to rise, operation will start once VIN exceeds the under-voltage lockout (UVLO)
threshold. To set EN high externally, pull it up to 1.2 V or higher. Note that the voltage on EN must remain at less
than VIN+ 0.2 V due to absolute maximum ratings of the device.
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
11
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
Device Functional Modes (continued)
7.4.5 Internal Synchronous Rectification
The LMZ10501 uses an internal NFET as a synchronous rectifier to minimize the switch voltage drop and
increase efficiency. The NFET is designed to conduct through its intrinsic body diode during the built-in dead time
between the PFET on-time and the NFET on-time. This eliminates the need for an external diode. The dead time
between the PFET and NFET connection prevents shoot through current from VIN to PGND during the switching
transitions.
7.4.6 High Duty Cycle Operation
The LMZ10501 features a transition mode designed to extend the output regulation range to the minimum
possible input voltage. As the input voltage decreases closer and closer to VOUT, the off-time of the PFET gets
smaller and smaller and the duty cycle eventually needs to reach 100% to support the output voltage. The input
voltage at which the duty cycle reaches 100% is the edge of regulation. When the LMZ10501 input voltage is
lowered, such that the off-time of the PFET reduces to less than 35ns, the LMZ10501 doubles the switching
period to extend the off-time for that VIN and maintain regulation. If VIN is lowered even more, the off-time of the
PFET will reach the 35ns mark again. The LMZ10501 will then reduce the frequency again, achieving less than
100% duty cycle operation and maintaining regulation. As VIN is lowered even more, the LMZ10501 will continue
to scale down the frequency, aiming to maintain at least 35ns off time. Eventually, as the input voltage decreases
further, 100% duty cycle is reached. This behavior of extending the VIN regulation range is illustrated in
Figure 11.
1V/Div
INPUT VOLTAGE
1V/Div
SWITCH NODE
20 MHz BW
5 µs/Div
Figure 11. High Duty Cycle Operation and Switching Frequency Reduction
12
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
This section describes a simple design procedure. Alternatively, WEBENCH® can be used to create and simulate
a design using the LMZ10501. The WEBENCH® tool can be accessed from the LMZ10501 product folder at
http://www.ti.com/product/lmz10501. For designs with typical output voltages (1.2 V, 1.8 V, 2.5 V, 3.3 V), jump to
the Application Curves section for quick reference designs.
8.2 Typical Application
EN
VREF
RT
VCON
RB
CVC
FB
VIN
CIN
10PF
PGND
SGND
VOUT
COUT
10PF
Figure 12. Typical Application Circuit
8.2.1 Design Requirements
The detailed design procedure is based on the required input and output voltage specifications for the design.
The input voltage range of the LMZ10501 is 2.7V to 5.5V. The output voltage range is 0.6V to 3.6V. The output
current capability is 1A.
8.2.2 Detailed Design Procedure
8.2.2.1 Setting The Output Voltage
The LMZ10501 provides a fixed 2.35V VREF voltage output. As shown in Figure 12 above, a resistive divider
formed by RT and RB sets the VCON pin voltage level. The VOUT voltage tracks VCON and is governed by the
following relationship:
VOUT = GAIN x VCON
where GAIN is 2.5V/V from VCON to VFB
(1)
This equation is valid for output voltages between 0.6V and 3.6V and corresponds to VCON voltage between
0.24V and 1.44V, respectively.
8.2.2.1.1 RT And RB Selection For Fixed VOUT
The parameters affecting the output voltage setting are the RT, RB, and the product of the VREF voltage x GAIN.
The VREF voltage is typically 2.35V. Since VCON is derived from VREF via RT and RB,
VCON = VREF x RB/ (RB + RT)
(2)
After substitution,
VOUT = VREF x GAIN x RB/ (RB + RT)
RT = (GAIN x VREF / VOUT – 1) x RB
(3)
(4)
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
13
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
Typical Application (continued)
The ideal product of GAIN x VREF = 5.875 V.
Choose RT to be between 80kΩ and 300kΩ. Then, RB can be calculated using Equation 5 below.
RB = (VOUT / (5.875 V – VOUT)) x RT
(5)
Note that the resistance of RT should be ≥ 80kΩ. This ensures that the VREF output current loading is not
exceeded and the reference voltage is maintained. The current loading on VREF should not be greater than 30
µA.
8.2.2.1.2 Output Voltage Accuracy Optimization
Each nano module is optimized to achieve high VOUT accuracy. Equation 1 shows that, by design, the output
voltage is a function of the VCON voltage and the gain from VCON to VFB. The voltage at VCON is derived from
VREF. Therefore, as shown in Equation 3, the accuracy of the output voltage is a function of the VREF x GAIN
product as well as the tolerance of the RT and RB resistors. The typical VREF x GAIN product by design is 5.875
V. Each nano module's VREF voltage is trimmed so that this product is as close to the ideal 5.875 V value as
possible, achieving high VOUT accuracy. See the Features Description section for the VREF x GAIN product
tolerance limits.
8.2.2.2 Dynamic Output Voltage Scaling
The VCON pin on the LMZ10501 can be driven externally by a DAC to scale the output voltage dynamically. The
output voltage VOUT = 2.5 V/V x VCON. When driving VCON with a source different than VREF place a 1.5kΩ resistor
in series with the VCON pin. Current limiting the external VCON helps to protect this pin and allows the VCON
capacitor to be fully discharged to 0V after fault conditions.
8.2.2.3 Integrated Inductor
The LMZ10501 includes an inductor with over 1.2A DC current rating and soft saturation profile for up to 2A. This
inductor allows for low package height and provides an easy to use, compact solution with reduced EMI.
8.2.2.4 Input And Output Capacitor Selection
The LMZ10501 is designed for use with low ESR multi-layer ceramic capacitors (MLCC) for its input and output
filters. Using a 10 µF 0603 or 0805 with 6.3V or 10V rating ceramic input capacitor typically provides sufficient
VIN bypass. Use of multiple 4.7 µF or 2.2 µF capacitors can also be considered. Ceramic capacitors with X5R
and X7R temperature characteristics are recommended for both input and output filters. These provide an
optimal balance between small size, cost, reliability, and performance for space sensitive applications.
The DC voltage bias characteristics of the capacitors must be considered when selecting the DC voltage rating
and case size of these components. The effective capacitance of an MLCC is typically reduced by the DC
voltage bias applied across its terminals. For example, a typical 0805 case size X5R 6.3 V 10 µF ceramic
capacitor may only have 4.8 µF left in it when a 5.0-V DC bias is applied. Similarly, a typical 0603 case size X5R
6.3V 10 µF ceramic capacitor may only have 2.4 µF at the same 5.0V DC. Smaller case size capacitors may
have even larger percentage drop in value with DC bias.
The optimum output capacitance value is application dependent. Too small output capacitance can lead to
instability due to lower loop phase margin. On the other hand, if the output capacitor is too large, it may prevent
the output voltage from reaching the 0.375 V required voltage level at the end of the startup sequence. In such
cases, the output short circuit protection can be engaged and the nano module will enter a hiccup mode as
described in the Output Short Circuit Protection section. Table 1 sets the minimum output capacitance for
stability and maximum output capacitance for proper startup for various output voltage settings. Note that the
maximum COUT value in Table 1 assumes that the filter capacitance on VCON is the maximum recommended
value of 1nF and the RT resistor value is less than 300kΩ. Lower VCON capacitance can extend the maximum
COUT range. There is no great performance benefit in using excessive COUT values.
14
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
Typical Application (continued)
Table 1. Output Capacitance Range
Output Voltage
Minimum
COUT
Suggested
COUT
Maximum
COUT
0.6V
4.7µF
10µF
47µF
1.0V
3.3µF
10µF
47µF
1.2V
3.3µF
10µF
47µF
1.8V
3.3µF
10µF
68µF
2.5V
3.3µF
10µF
100µF
3.3V
3.3µF
10µF
100µF
Use of multiple 4.7-µF or 2.2-µF output capacitors can be considered for reduced effective ESR and smaller
output voltage ripple. In addition to the main output capacitor, small 0.1-µF – 0.01-µF parallel capacitors can be
used to reduce high frequency noise.
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
15
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
8.2.3 Application Curves
8.2.3.1 VOUT = 1.2 V
VIN
VIN
EN
100
1.2V
VOUT
CIN
90
VOUT
80
EFFICIENCY (%)
VREF
FB
RT
VCON
COUT
PGND
RB
SGND
CVC
70
60
50
VIN=2.7V
VIN=3.3V
VIN=3.6V
VIN=5V
VIN=5.5V
40
CIN
COUT
CVC
RT
RB
10 P)86.3V
10 PF 86.3V
470 pF 86.3V
243 k: 1%
63.4 k: 1%
0805 X7R or X5R
0805 X7R or X5R
0603 X7R or X5R
0603
0603
30
20
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
LOAD CURRENT (A)
1
C001
Figure 14. Efficiency VOUT = 1.2 V
Figure 13. Schematic VOUT = 1.2 V
COUT = 10F 10V 0805 X5R
VOUT RIPPLE
COUT = 10F 10V 0805 X5R
50mV/Div
OUTPUT VOLTAGE
10mV/Div
LOAD CURRENT
500mA/Div
250MHz BW
1µs/Div
20 MHz BW
Figure 15. Output Ripple VOUT = 1.2 V
Figure 16. Load Transient VOUT = 1.2 V
1.8
VIN=2.7V
VIN=3.3V
VIN=3.6V
VIN=5V
VIN=5.5V
1.23
1.7
DC CURRENT LIMIT (A)
OUTPUT VOLTAGE (V)
1.24
500 µs/Div
1.22
1.21
1.6
1.5
1.4
1.3
1.2
1.1
1.0
1.20
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
LOAD CURRENT (A)
Figure 17. Line and Load Regulation VOUT = 1.2 V
16
2.5
3.0
3.5
4.0
4.5
INPUT VOLTAGE (V)
C002
5.0
5.5
C001
Figure 18. DC Current Limit VOUT = 1.2 V, TA=85°C
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
8.2.3.2 VOUT = 1.8 V
VIN
VIN
EN
100
1.8V
VOUT
CIN
90
VOUT
80
EFFICIENCY (%)
VREF
FB
RT
VCON
COUT
PGND
RB
SGND
CVC
70
60
50
VIN=2.7V
VIN=3.3V
VIN=3.6V
VIN=5V
VIN=5.5V
40
CIN
COUT
CVC
RT
RB
10 P)86.3V
10 PF 86.3V
470 pF 86.3V
187 k: 1%
82.5 k: 1%
0805 X7R or X5R
0805 X7R or X5R
0603 X7R or X5R
0603
0603
30
20
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
LOAD CURRENT (A)
1.0
C001
Figure 20. Efficiency VOUT = 1.8 V
Figure 19. Schematic VOUT = 1.8 V
COUT = 10F 10V 0805 X5R
VOUT RIPPLE
COUT = 10F 10V 0805 X5R
50mV/Div
OUTPUT VOLTAGE
10mV/Div
LOAD CURRENT
500mA/Div
250MHz BW
1µs/Div
20 MHz BW
Figure 21. Output Ripple VOUT = 1.8 V
Figure 22. Load Transient VOUT = 1.8 V
1.8
VIN=2.7V
VIN=3.3V
VIN=3.6V
VIN=5V
VIN=5.5V
1.80
1.7
DC CURRENT LIMIT (A)
OUTPUT VOLTAGE (V)
1.81
500 µs/Div
1.79
1.78
1.6
1.5
1.4
1.3
1.2
1.1
1.77
1.0
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
LOAD CURRENT (A)
2.5
Figure 23. Line and Load Regulation VOUT = 1.8 V
3.0
3.5
4.0
4.5
5.0
INPUT VOLTAGE (V)
C001
5.5
C002
Figure 24. DC Current Limit VOUT = 1.8 V, TA= 85°C
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
17
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
8.2.3.3 VOUT = 2.5 V
VIN
VIN
EN
100
2.5V
VOUT
CIN
90
VOUT
80
EFFICIENCY (%)
VREF
FB
RT
VCON
COUT
PGND
RB
SGND
CVC
70
60
50
VIN=3.3V
VIN=3.6V
VIN=5V
VIN=5.5V
40
CIN
COUT
CVC
RT
RB
10 P)86.3V
10 PF 86.3V
470 pF 86.3V
150 k: 1%
118 k: 1%
0805 X7R or X5R
0805 X7R or X5R
0603 X7R or X5R
0603
0603
30
20
0.0
0.2
0.4
0.6
0.8
LOAD CURRENT (A)
1.0
C003
Figure 26. Efficiency VOUT = 2.5 V
Figure 25. Schematic VOUT = 2.5 V
COUT = 10F 10V 0805 X5R
VOUT RIPPLE
COUT = 10F 10V 0805 X5R
50mV/Div
OUTPUT VOLTAGE
10mV/Div
LOAD CURRENT
500mA/Div
250MHz BW
1µs/Div
20 MHz BW
Figure 28. Load Transient VOUT = 2.5 V
Figure 27. Output Ripple VOUT = 2.5 V
1.8
VIN=3.3V
VIN=3.6V
VIN=5V
VIN=5.5V
2.60
1.7
DC CURRENT LIMIT (A)
OUTPUT VOLTAGE (V)
2.65
500 µs/Div
2.55
2.50
1.6
1.5
1.4
1.3
1.2
1.1
1.0
2.45
0.0
0.2
0.4
0.6
0.8
1.0
LOAD CURRENT (A)
Figure 29. Line and Load Regulation VOUT = 2.5 V
18
2.5
3.0
3.5
4.0
4.5
INPUT VOLTAGE (V)
C004
5.0
5.5
C003
Figure 30. DC Current Limit VOUT = 2.5 V, TA= 85°C
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
8.2.3.4 VOUT = 3.3 V
VIN
VIN
EN
100
3.3V
VOUT
CIN
90
VOUT
80
EFFICIENCY (%)
VREF
FB
RT
VCON
COUT
PGND
RB
SGND
CVC
70
60
50
40
CIN
COUT
CVC
RT
RB
10 P)86.3V
10 PF 86.3V
470 pF 86.3V
118 k: 1%
150 k: 1%
0805 X7R or X5R
0805 X7R or X5R
0603 X7R or X5R
0603
0603
VIN=4V
VIN=4.5V
VIN=5V
VIN=5.5V
30
20
0.0
0.2
0.4
0.6
0.8
LOAD CURRENT (A)
1.0
C001
Figure 32. Efficiency VOUT = 3.3 V
Figure 31. Schematic VOUT = 3.3 V
COUT = 10F 10V 0805 X5R
VOUT RIPPLE
COUT = 10F 10V 0805 X5R
50mV/Div
OUTPUT VOLTAGE
10mV/Div
LOAD CURRENT
500mA/Div
250MHz BW
1µs/Div
20 MHz BW
Figure 34. Load Transient VOUT = 3.3 V
3.30
1.8
3.29
1.7
DC CURRENT LIMIT (A)
OUTPUT VOLTAGE (V)
Figure 33. Output Ripple VOUT = 3.3 V
3.28
3.27
3.26
3.25
3.24
VIN=4V
VIN=4.5V
VIN=5V
VIN=5.5V
3.23
3.22
0.0
0.2
0.4
0.6
0.8
500 µs/Div
1.6
1.5
1.4
1.3
1.2
1.1
1.0
1.0
LOAD CURRENT (A)
2.5
Figure 35. Line and Load Regulation VOUT = 3.3 V
3.0
3.5
4.0
4.5
5.0
INPUT VOLTAGE (V)
C002
5.5
C004
Figure 36. DC Current Limit VOUT = 3.3 V, TA= 85°C
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
19
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
9 Power Supply Recommendations
9.1 Voltage Range
The voltage of the input supply must not exceed the Absolute Maximum Ratings and the Recommended
Operating Conditions of the LMZ10501.
9.2 Current Capability
The input supply must be able to supply the required input current to the LMZ10501 converter. The required
input current depends on the application's minimum required input voltage (VIN-MIN), the required output power
(VOUT x IOUT-MAX), and the converter efficiency (η).
IIN = VOUT x IOUT-MAX / (VIN-MIN x η)
(6)
For example, for a design with 5-V minimum input voltage,1.8-V output, and 1-A maximum load, considering 82%
conversion efficiency, the required input current at steady state is 0.439A.
9.3 Input Connection
Long input connection cables can cause issues with the normal operation of any Buck converter.
9.3.1 Voltage Drops
Using long input wires to connect the supply to the input of any converter adds impedance in series with the
input supply. This impedance can cause a voltage drop at the VIN pin of the converter when the output of the
converter is loaded. If the input voltage is near the minimum operating voltage, this added voltage drop can
cause the converter to drop out or reset. If long wires are used during testing, it is recommended to add some
bulk (i.e. electrolytic) capacitance at the input of the converter.
9.3.2 Stability
The added inductance of long input cables together with the ceramic (and low ESR) input capacitor can result in
an under damped RLC network at the input of the Buck converter. This can cause oscillations on the input and
instability. If long wires are used, it is recommended to add some electrolytic capacitance in parallel with the
ceramic input capacitor. The electrolytic capacitor's ESR will improve the damping.
Use an electrolytic capacitor with CELECTROLYTIC≥ 4xCCERAMIC and ESRELECTROLYTIC≈ √ (LCABLE / CCERAMIC)
For example, two cables (one for VIN and one for GND), each 1 meter (~3ft) long with ~1.0mm diameter
(18AWG), placed 1cm (~0.4in) apart will form a rectangular loop resulting in about 1.2µH of inductance. The
inductance in this example can be decreased to almost half if the input wires are twisted. Based on a 10µF
ceramic input capacitor, the recommended parallel CELECTROLYTIC is ≥ 40 µF. Using a 47µF capacitor will be
sufficient. The recommended ESRELECTROLYTIC≈ 0.35Ω or larger, based on about 1.2µH of inductance and 10µF
of ceramic input capacitance.
See application note SNVA489 for more details on input filter design.
20
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
10 Layout
10.1 Layout Guidelines
The board layout of any DC-DC switching converter is critical for the optimal performance of the design. Bad
PCB layout design can disrupt the operation of an otherwise good schematic design. Even if the regulator still
converts the voltage properly, the board layout can mean the difference between passing or failing EMI
regulations. In a Buck converter, the most critical board layout path is between the input capacitor ground
terminal and the synchronous rectifier ground. The loop formed by the input capacitor and the power FETs is a
path for the high di/dt switching current during each switching period. This loop should always be kept as short
as possible when laying out a board for any Buck converter.
The LMZ10501 integrates the inductor and simplifies the DC-DC converter board layout. Refer to the example
layout in Figure 37. There are a few basic requirements to achieve a good LMZ10501 layout.
1. Place the input capacitor CIN as close as possible to the VIN and PGND pins. VIN (pin 7) and PGND (pin 6) on
the LMZ10501 are next to each other which makes the input capacitor placement simple.
2. Place the VCON filter capacitor CVC and the RB RT resistive divider as close as possible to the VCON and SGND
pins. The CVC capacitor (not RB) should be the component closer to the VCON pin, as shown in Figure 37. This
allows for better bypass of the control voltage set at VCON.
3. Run the feedback trace (from VOUT to FB) away from noise sources.
4. Connect SGND to a quiet GND plane.
5. Provide enough PCB area for proper heatsinking. Refer to the Electrical Characteristics table for example θJA
values for different board areas. Also, refer to AN-2020 for additional thermal design hints.
Refer to the evaluation board user guide SNVU313 for a complete board layout example.
10.2 Layout Example
RB
RESISTOR
RT
RESISTOR
HIGH di/dt LOOP
KEEP IT SMALL
EN
VREF
VCON
VIN
FB
PGND
SGND
VOUT
VIN
INPUT
CAPACITOR
PGND
VOUT
FEEDBACK
TRACE
SGND CONNECTION TO
QUIET PGND PLANE
OUTPUT
CAPACITOR
VCON
CAPACITOR
Figure 37. Example Top Layer Board Layout
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
21
LMZ10501
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
www.ti.com
10.3 Package Considerations
Use the following recommendations when utilizing machine placement :
• Use 1.06mm (42mil) or smaller nozzle size. The pick up area is the top of the inductor which is 1.6mm x
2mm.
• Soft tip pick and place nozzle is recommended.
• Add 0.05mm to the component thickness so that the device will be released 0.05mm (2mil) into the solder
paste without putting pressure or splashing the solder paste.
• Slow the pick arm when picking the part from the tape and reel carrier and when depositing the IC on the
board.
• If the machine releases the component by force, use minimum force or no more than 3 Newtons.
For manual placement:
• Use a vacuum pick up hand tool with soft tip head.
• If vacuum pick up tool is not available, use non-metal tweezers and hold the part by sides.
• Use minimal force when picking and placing the module on the board.
• Using hot air station provides better temperature control and better controlled air flow than a heat gun.
• Go to the video section at www.ti.com/product/lmz10501 for a quick video on how to solder rework the
LMZ10501.
22
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
LMZ10501
www.ti.com
SNVS677F – MAY 2011 – REVISED NOVEMBER 2014
11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
• AN-2162 Simple Success With Conducted EMI From DC- DC Converters, SNVA489
• MZ10501SIL and LMZ10500SIL SIMPLE SWITCHER® Nano Module Evaluation Board, SNVU313
11.2 Trademarks
SIMPLE SWITCHER, WEBENCH are registered trademarks of Texas Instruments.
All other trademarks are the property of their respective owners.
11.3 Electrostatic Discharge Caution
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.
11.4 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
Submit Documentation Feedback
Copyright © 2011–2014, Texas Instruments Incorporated
Product Folder Links: LMZ10501
23
PACKAGE OPTION ADDENDUM
www.ti.com
13-Jun-2015
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
LMZ10501SH/NOPB
OBSOLETE
POS
NQB
8
TBD
Call TI
Call TI
-40 to 85
SP
LMZ10501SHE/NOPB
OBSOLETE
POS
NQB
8
TBD
Call TI
Call TI
-40 to 85
SP
LMZ10501SHX/NOPB
OBSOLETE
POS
NQB
8
TBD
Call TI
Call TI
-40 to 85
SP
LMZ10501SILR
ACTIVE
uSiP
SIL
8
3000
Green (RoHS
& no Sb/Br)
Call TI
Level-3-260C-168 HR
-40 to 125
TXN5010EC
(501 ~ DG)
9811
0501
0501 9811 DG
LMZ10501SILT
ACTIVE
uSiP
SIL
8
250
Green (RoHS
& no Sb/Br)
Call TI
Level-3-260C-168 HR
-40 to 125
TXN5010EC
(501 ~ DG)
9811
0501
0501 9811 DG
(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.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
13-Jun-2015
(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.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
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.
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
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other
changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest
issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and
complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale
supplied at the time of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and
applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration
and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered
documentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which
anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use
of any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to
help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and
requirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in
military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and
regulatory requirements in connection with such use.
TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use of
non-designated products, TI will not be responsible for any failure to meet ISO/TS16949.
Products
Applications
Audio
www.ti.com/audio
Automotive and Transportation
www.ti.com/automotive
Amplifiers
amplifier.ti.com
Communications and Telecom
www.ti.com/communications
Data Converters
dataconverter.ti.com
Computers and Peripherals
www.ti.com/computers
DLP® Products
www.dlp.com
Consumer Electronics
www.ti.com/consumer-apps
DSP
dsp.ti.com
Energy and Lighting
www.ti.com/energy
Clocks and Timers
www.ti.com/clocks
Industrial
www.ti.com/industrial
Interface
interface.ti.com
Medical
www.ti.com/medical
Logic
logic.ti.com
Security
www.ti.com/security
Power Mgmt
power.ti.com
Space, Avionics and Defense
www.ti.com/space-avionics-defense
Microcontrollers
microcontroller.ti.com
Video and Imaging
www.ti.com/video
RFID
www.ti-rfid.com
OMAP Applications Processors
www.ti.com/omap
TI E2E Community
e2e.ti.com
Wireless Connectivity
www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2015, Texas Instruments Incorporated