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LMZ10501
SNVS677G – MAY 2011 – REVISED JULY 2018
LMZ10501 1-A Nano Module With 5.5-V Maximum Input Voltage
1 Features
2 Applications
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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 microSiP Footprint
–40°C to 125°C Junction Temperature Range
Adjustable Output Voltage
2-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 Brownout 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
Create a Custom Design Using the LMZ10501
With the WEBENCH® Power Designer
•
•
Point of Load Conversions From 3.3-V and 5-V
Rails
Space Constrained Applications
Low Output Noise Applications
3 Description
The LMZ10501 nano module is an easy-to-use stepdown 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 µSIP
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 V, VOUT = 1.8 V, IOUT = 1 A
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 × 2.60 mm
(1) For all available packages, see the orderable addendum at
the end of the datasheet.
100
40
PACKAGE
µSIP(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
SNVS677G – MAY 2011 – REVISED JULY 2018
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
Detailed Description .............................................. 9
7.1
7.2
7.3
7.4
8
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
System Characteristics .............................................
Typical Characteristics ..............................................
Overview ................................................................... 9
Functional Block Diagram ......................................... 9
Feature Description................................................... 9
Device Functional Modes........................................ 11
Application and Implementation ........................ 13
8.1 Application Information............................................ 13
8.2 Typical Application ................................................. 13
9
Power Supply Recommendations...................... 21
9.1 Voltage Range ........................................................ 21
9.2 Current Capability ................................................... 21
9.3 Input Connection .................................................... 21
10 Layout................................................................... 22
10.1 Layout Guidelines ................................................. 22
10.2 Layout Example .................................................... 22
10.3 Package Considerations ....................................... 23
11 Device and Documentation Support ................. 24
11.1
11.2
11.3
11.4
11.5
11.6
11.7
Device Support......................................................
Documentation Support ........................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
24
24
24
24
24
24
25
12 Mechanical, Packaging, and Orderable
Information ........................................................... 25
12.1 Tape and Reel Information ................................... 25
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision F (November 2014) to Revision G
Page
•
Editorial rebranding for SEO................................................................................................................................................... 1
•
Added links for Webench and top navigator icon for TI reference design ............................................................................ 1
•
Move storage temperature spec to Abs Max table ................................................................................................................ 4
•
Changed "Handling" to "ESD" Ratings .................................................................................................................................. 4
•
Added Device Support ......................................................................................................................................................... 24
•
Changed SIL package drawing to SIL0008G ...................................................................................................................... 25
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
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SNVS677G – MAY 2011 – REVISED JULY 2018
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 1.2 V 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 4.7 µF and 22 µF.
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. Connect this
pad to the ground plane for improved thermal performance.
PAD
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SNVS677G – MAY 2011 – REVISED JULY 2018
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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 max
V
VOUT
(PGND
−0.2)
(VIN +0.2)
w/6 max
V
−40
125
°C
260
°C
150
°C
Junction temperature (TJ-MAX)
Maximum lead temperature
Storage temperature, Tstg
(1)
(2)
(3)
–65
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, 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 ESD Ratings
VALUE
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001
V(ESD)
(1)
(2)
Electrostatic discharge
(1)
UNIT
±1000
Charged-device model (CDM), per JEDEC specification JESD22C101 (2)
±250
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)
MIN
Input voltage
Recommended load current
Junction temperature, TJ
MAX
UNIT
2.7
5.5
0
1000
mA
V
−40
125
°C
6.4 Thermal Information
LMZ10501
THERMAL METRIC
(1)
SIL (µSIP)
UNIT
8 PINS
(2)
RθJA
Junction-to-ambient thermal resistance
45.8
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
25
°C/W
RθJB
Junction-to-board thermal resistance
9.2
°C/W
ψJT
Junction-to-top characterization parameter
1.5
°C/W
ψJB
Junction-to-board characterization parameter
9.1
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
25
°C/W
(1)
(2)
4
SIL0008G Package
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
Junction-to-ambient thermal resistance (RθJA) 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. RθJA varies with PCB copper area, power dissipation, and airflow.
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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 × GAIN
Reference voltage × VCON to
FB bain
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
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
ISHDN
(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
(1)
(2)
(3)
(4)
V
0.5
Rising Threshold
V
150
°C
20
°C
100%
50
SIL0008A Package Thermal
Resistance
θJA
mA
20mm x 20mm board
2 layers, 2 oz copper, 0.5W,
no airlow
77
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
ns
°C/W
Min and Max limits are 100% production tested at 25°C. Limits over the operating temperature range are specified 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
TEST CONDITIONS
MIN
TYP
ΔVOUT/VOU Output voltage regulation over line
voltage and load current
T
VOUT = 0.6 V
ΔVIN = 2.7 V to 4.2 V
ΔIOUT = 0A to 1A
±1.75%
ΔVOUT/VOU Output voltage regulation over line
voltage and load current
T
VOUT = 1.5 V
ΔVIN = 2.7 V to 5.5 V
ΔIOUT = 0A to 1A
±0.92%
ΔVOUT/VOU Output voltage regulation over line
voltage and load current
T
VOUT = 3.6 V
ΔVIN = 4.0 V to 5.5 V
ΔIOUT = 0A to 1A
±0.38%
VREF
TRISE
EN = Low to High, VIN = 4.2 V
VOUT = 2.7 V, IOUT = 1A
Rise time of reference voltage
MAX
UNIT
10
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5
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SNVS677G – MAY 2011 – REVISED JULY 2018
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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
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
VIN = 2.7 V to 5.5 V,
TR = TF= 10 µs,
VOUT = 1.8 V, IOUT = 1000 mA
30
mV pk-pk
Line transient response
mV pk-pk
Load transient response
VIN = 5.0 V
TR = TF = 40 µs,
VOUT = 1.8 V
IOUT = 100 mA to 1000 mA
30
Load
Transient
η
6
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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 V, VOUT = 1.8 V, IOUT
= 1-A Default Evaluation Board BOM
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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
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Figure 8. Startup
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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.
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Feature Description (continued)
7.3.2 Startup Behavior and Soft Start
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 Soft Start 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
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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 790-kΩ (typical) 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.
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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
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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 Custom Design With WEBENCH® Tools
Click here to create a custom design using the LMZ10501 device with the WEBENCH® Power Designer.
1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements.
2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial.
3. Compare the generated design with other possible solutions from Texas Instruments.
The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time
pricing and component availability.
In most cases, these actions are available:
• Run electrical simulations to see important waveforms and circuit performance
• Run thermal simulations to understand board thermal performance
• Export customized schematic and layout into popular CAD formats
• Print PDF reports for the design, and share the design with colleagues
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Typical Application (continued)
8.2.2.2 Setting The Output Voltage
The LMZ10501 provides a fixed 2.35-V 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.
8.2.2.2.1 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 × GAIN.
The VREF voltage is typically 2.35V. Since VCON is derived from VREF via RT and RB,
VCON = VREF × RB/ (RB + RT)
(2)
After substitution,
VOUT = VREF × GAIN × RB/ (RB + RT)
RT = (GAIN x VREF / VOUT – 1) × RB
(3)
(4)
The ideal product of GAIN × 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)) × 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.
8.2.2.2.2 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.
8.2.2.3 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.
8.2.2.4 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.
8.2.2.5 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.
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Typical Application (continued)
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.
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Typical Application (continued)
Table 1. Output Capacitance Range
OUTPUT VOLTAGE
MINIMUM
COUT
SUGGESTED
COUT
MAXIMUM
COUT
0.6 V
4.7 µF
10 µF
47 µF
1V
3.3 µF
10 µF
47 µF
1.2 V
3.3 µF
10 µF
47 µF
1.8 V
3.3 µF
10 µF
68 µF
2.5 V
3.3 µF
10 µF
100 µF
3.3 V
3.3 µF
10 µF
100 µF
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.
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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) 8 6.3V
10 PF 8 6.3V
470 pF 8 6.3V
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 = 10 F 10V 0805 X5R
VOUT RIPPLE
COUT = 10 F 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)
2.5
Figure 17. Line and Load Regulation VOUT = 1.2 V
3.0
3.5
4.0
4.5
5.0
INPUT VOLTAGE (V)
C002
5.5
C001
Figure 18. DC Current Limit VOUT = 1.2 V, TA=85°C
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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) 8 6.3V
10 PF 8 6.3V
470 pF 8 6.3V
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 = 10 F 10V 0805 X5R
VOUT RIPPLE
COUT = 10 F 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)
Figure 23. Line and Load Regulation VOUT = 1.8 V
18
2.5
3.0
3.5
4.0
4.5
INPUT VOLTAGE (V)
C001
5.0
5.5
C002
Figure 24. DC Current Limit VOUT = 1.8 V, TA= 85°C
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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) 8 6.3V
10 PF 8 6.3V
470 pF 8 6.3V
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 = 10 F 10V 0805 X5R
VOUT RIPPLE
COUT = 10 F 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)
2.5
Figure 29. Line and Load Regulation VOUT = 2.5 V
3.0
3.5
4.0
4.5
5.0
INPUT VOLTAGE (V)
C004
5.5
C003
Figure 30. DC Current Limit VOUT = 2.5 V, TA= 85°C
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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) 8 6.3V
10 PF 8 6.3V
470 pF 8 6.3V
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 = 10 F 10V 0805 X5R
VOUT RIPPLE
COUT = 10 F 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
1.6
1.5
1.4
1.3
1.2
1.1
1.0
1.0
LOAD CURRENT (A)
2.5
3.0
3.5
4.0
4.5
INPUT VOLTAGE (V)
C002
Figure 35. Line and Load Regulation VOUT = 3.3 V
20
500 µs/Div
5.0
5.5
C004
Figure 36. DC Current Limit VOUT = 3.3 V, TA= 85°C
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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 × IOUT-MAX), and the converter efficiency (η).
IIN = VOUT × IOUT-MAX / (VIN-MIN × 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 0.439 A.
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≥ 4 × CCERAMIC and ESRELECTROLYTIC≈ √ (LCABLE / CCERAMIC)
For example, two cables (one for VIN and one for GND), each 1 meter (~3 ft) long with ~1 mm diameter
(18AWG), placed 1cm (~0.4 in) 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 47-µF capacitor will be
sufficient. The recommended ESRELECTROLYTIC≈ 0.35Ω or larger, based on about 1.2 µH of inductance and 10 µF
of ceramic input capacitance.
See application note SNVA489 for more details on input filter design.
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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 heat sinking. 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
PGND
INPUT
CAPACITOR
VOUT
FEEDBACK
TRACE
SGND CONNECTION TO
QUIET PGND PLANE
OUTPUT
CAPACITOR
VCON
CAPACITOR
Figure 37. Example Top Layer Board Layout
22
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LMZ10501
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10.3 Package Considerations
Use the following recommendations when utilizing machine placement :
• Use 1.06 mm (42mil) or smaller nozzle size. The pick up area is the top of the inductor which is 1.6 mm × 2
mm.
• Soft tip pick and place nozzle is recommended.
• Add 0.05 mm to the component thickness so that the device will be released 0.05 mm (2 mil) 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.
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LMZ10501
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www.ti.com
11 Device and Documentation Support
11.1 Device Support
11.1.1 Custom Design With WEBENCH® Tools
Click here to create a custom design using the LMZ10501 device with the WEBENCH® Power Designer.
1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements.
2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial.
3. Compare the generated design with other possible solutions from Texas Instruments.
The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time
pricing and component availability.
In most cases, these actions are available:
• Run electrical simulations to see important waveforms and circuit performance
• Run thermal simulations to understand board thermal performance
• Export customized schematic and layout into popular CAD formats
• Print PDF reports for the design, and share the design with colleagues
Get more information about WEBENCH tools at www.ti.com/WEBENCH.
11.2 Documentation Support
11.2.1 Related Documentation
• AN-2162 Simple Success With Conducted EMI From DC- DC Converters
•
• LMZ10501SIL and LMZ10500SIL SIMPLE SWITCHER® Nano Module Evaluation Board
11.3 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.4 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.5 Trademarks
E2E is a trademark of Texas Instruments.
WEBENCH is a registered trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
11.6 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.
24
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LMZ10501
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SNVS677G – MAY 2011 – REVISED JULY 2018
11.7 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.
12.1 Tape and Reel Information
REEL DIMENSIONS
TAPE DIMENSIONS
K0
P1
B0 W
Reel
Diameter
Cavity
A0
B0
K0
W
P1
A0
Dimension designed to accommodate the component width
Dimension designed to accommodate the component length
Dimension designed to accommodate the component thickness
Overall width of the carrier tape
Pitch between successive cavity centers
Reel Width (W1)
QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE
Sprocket Holes
Q1
Q2
Q1
Q2
Q3
Q4
Q3
Q4
User Direction of Feed
Pocket Quadrants
Device
Package
Type
Package
Drawing
Pins
SPQ
Reel
Diameter
(mm)
Reel
Width W1
(mm)
A0
(mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
(mm)
Pin1
Quadrant
LMZ10501SILR
uSiP
SIL
8
3000
330.0
12.4
2.85
3.25
1.7
4.0
12.0
Q1
LMZ10501SILT
uSiP
SIL
8
250
178.0
13.2
2.85
3.25
1.7
4.0
12.0
Q1
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LMZ10501
SNVS677G – MAY 2011 – REVISED JULY 2018
www.ti.com
TAPE AND REEL BOX DIMENSIONS
Width (mm)
L
W
26
H
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LMZ10501SILR
uSiP
SIL
8
3000
383.0
353.0
58.0
LMZ10501SILT
uSiP
SIL
8
250
223.0
194.0
35.0
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PACKAGE OUTLINE
SIL0008G
uSiP - 1.5mm max height
SCALE 5. 000
MICRO SYSTEM IN PACKAGE
2.7
2.5
B
(2)
3.1
2.9
(1.6)
A
INDUCTOR
SUBSTRATE
1.5 MAX
C
0.08 C
0.45
0.37
8X
0.1
(0.7)
0.7
0.5
4X (0.15)
0.4
8X
0.2
C A B
8X (0.7)
8X (0.4)
5
4
(2.35)
2X
3X (0.65)
4X (0.15)
2.25
0.1
1.95
1
(45 X0.15)
PIN 1 ID
8
6X 0.65
(0.05)
ALL AROUND
0.6 0.1
4224244/A 04/2018
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. Pick and place nozzle 1.3 mm or smaller recommended.
www.ti.com
EXAMPLE BOARD LAYOUT
SIL0008G
uSiP - 1.5mm max height
MICRO SYSTEM IN PACKAGE
(1.9)
2X ( 0.2)
VIA
(0.6)
8
1
6X
(0.65)
SYMM
(1.95)
(2.25)
(0.41)
4
5
SYMM
8X (0.3)
SEE DETAILS
8X (0.6)
LAND PATTERN EXAMPLE
1:1 RATIO WITH PACKAGE SOLDER PADS
SCALE: 20X
0.07 MIN
ALL AROUND
0.07 MAX
ALL AROUND
SOLDERMASK
OPENING
METAL EDGE
EXPOSED
METAL
SOLDER MASK
OPENING
EXPOSED
METAL
NON SOLDER MASK
DEFINED
METAL
SOLDER MASK
DEFINED
SOLDER MASK DETAILS
NOT TO SCALE
4224244/A 04/2018
NOTES: (continued)
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature
number SLUA271 (www.ti.com/lit/slua271).
www.ti.com
EXAMPLE STENCIL DESIGN
SIL0008G
uSiP - 1.5mm max height
MICRO SYSTEM IN PACKAGE
(1.9)
(0.6)
3X
(0.62)
6X
(0.65)
8
1
(0.816)
SYMM
(1.95)
4
8X (0.3)
5
SYMM
2X METAL
8X (0.6)
SOLDER PASTE EXAMPLE
BASED ON 0.125 MM THICK STENCIL
82% PRINTED SOLDER COVERAGE BY AREA
SCALE: 20X
4224244/A 04/2018
NOTES: (continued)
5. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
www.ti.com
PACKAGE OPTION ADDENDUM
www.ti.com
20-Feb-2021
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
(3)
Device Marking
(4/5)
(6)
LMZ10501SILR
ACTIVE
uSiP
SIL
8
3000
RoHS & Green
NIAU
Level-3-260C-168 HR
-40 to 125
501
0501 9811 DG
LMZ10501SILT
ACTIVE
uSiP
SIL
8
250
RoHS & Green
NIAU
Level-3-260C-168 HR
-40 to 125
501
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)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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