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LM2830, LM2830-Q1
SNVS454E – AUGUST 2006 – REVISED DECEMBER 2014
LM2830/-Q1 High-Frequency 1.0-A Load Step-Down DC-DC Regulator
1 Features
3 Description
•
The LM2830 regulator is a monolithic, highfrequency, PWM step-down DC-DC converter in a 5pin SOT-23 and a 6-Pin WSON package. The device
provides all the active functions to provide local DCDC conversion with fast transient response and
accurate regulation in the smallest possible PCB
area. With a minimum of external components, the
LM2830 regulator is easy to use. The ability to drive
1.0-A loads with an internal 130-mΩ PMOS switch
using state-of-the-art 0.5-µm BiCMOS technology
results in the best power density available. The worldclass control circuitry allows on-times as low as 30
ns, thus supporting exceptionally high frequency
conversion over the entire 3-V to 5.5-V input
operating range down to the minimum output voltage
of 0.6 V. Switching frequency is internally set to 1.6
MHz, or 3.0 MHz, allowing the use of extremely small
surface-mount inductors and chip capacitors. Even
though the operating frequency is high, efficiencies
up to 93% are easy to achieve. External shutdown is
included, featuring an ultra-low standby current of 30
nA. The LM2830 regulator uses current-mode control
and internal compensation to provide highperformance regulation over a wide range of
operating conditions. Additional features include
internal soft-start circuitry to reduce inrush current,
pulse-by-pulse current limit, thermal shutdown, and
output overvoltage protection.
1
•
•
•
•
•
•
•
•
•
•
•
LM2830Z-Q1 and LM2830X-Q1 in the SOT-23
Package are Automotive-Grade Products that are
AEC-Q100 Grade 1 Qualified (–40°C to +125°C
Operating Junction Temperature)
Space-Saving SOT-23 Package
Input Voltage Range of 3.0 V to 5.5 V
Output Voltage Range of 0.6 V to 4.5 V
1.0-A Output Current
High Switching Frequencies
– 1.6 MHz (LM2830X)
– 3.0 MHz (LM2830Z)
130-mΩ PMOS Switch
0.6-V, 2% Internal Voltage Reference
Internal Soft-Start
Current Mode, PWM Operation
Thermal Shutdown
Overvoltage Protection
2 Applications
•
•
•
•
•
•
Local 5-V to Vcore Step-Down Converters
Core Power in HDDs
Set-Top Boxes
USB Powered Devices
DSL Modems
Automotive
Device Information(1)
PART NUMBER
LM2830
LM2830-Q1
PACKAGE
BODY SIZE (NOM)
SOT (5)
2.90 mm × 1.60 mm
WSON (6)
3.00 mm × 3.00 mm
SOT (5)
2.90 mm × 1.60 mm
(1) For all available packages, see the orderable addendum at
the end of the datasheet.
Typical Application Circuit
FB
EN
LM2830
R3
VIN
Efficiency vs Load Current
GND
L1
SW
VO = 3.3V @ 1.0A
VIN = 5V
R1
C1
D1
C2
C3
R2
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.
LM2830, LM2830-Q1
SNVS454E – AUGUST 2006 – REVISED DECEMBER 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
4
5
6
Absolute Maximum Ratings ......................................
ESD Ratings: LM2830 ..............................................
ESD Ratings: LM2830-Q1 ........................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Typical Characteristics ..............................................
Detailed Description .............................................. 9
7.1 Overview ................................................................... 9
7.2 Functional Block Diagram ....................................... 10
7.3 Feature Description................................................. 10
7.4 Device Functional Modes........................................ 11
8
Application and Implementation ........................ 12
8.1 Application Information............................................ 12
8.2 Typical Applications ................................................ 12
9 Power Supply Recommendations...................... 24
10 Layout................................................................... 24
10.1
10.2
10.3
10.4
Layout Guidelines .................................................
Layout Example ....................................................
Thermal Considerations ........................................
WSON Package ....................................................
24
24
25
27
11 Device and Documentation Support ................. 28
11.1
11.2
11.3
11.4
11.5
Device Support......................................................
Related Links ........................................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
28
28
28
28
29
12 Mechanical, Packaging, and Orderable
Information ........................................................... 29
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision D (April 2013) to Revision E
•
Page
Added Pin Configuration and Functions section, ESD Ratings 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 C (April 2013) to Revision D
•
2
Page
Changed layout of National Data Sheet to TI format ........................................................................................................... 23
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SNVS454E – AUGUST 2006 – REVISED DECEMBER 2014
5 Pin Configuration and Functions
WSON Package
6-Pin
Top View
FB
1
GND
2
SW
3
6 EN
DAP
5 VINA
4 VIND
SOT Package
5-Pins
Top View
EN
4
3
FB
2 GND
VIN
5
1
SW
Pin Functions (5-Pin SOT)
PIN
NAME
NO.
I/O (1)
DESCRIPTION
SW
1
O
Output switch. Connect to the inductor and catch diode.
GND
2
G
Signal and power ground pin. Place the bottom resistor of the feedback network as close as
possible to this pin.
FB
3
I
Feedback pin. Connect to external resistor divider to set output voltage.
EN
4
I
Enable control input. Logic high enables operation. Do not allow this pin to float or be greater
than VIN + 0.3 V.
VIN
5
I/P
(1)
Input supply voltage.
I: Input Pin, O: Output Pin, P: Power Pin, G: Ground Pin
Pin Functions (6-Pin WSON)
PIN
NAME
NO.
I/O (1)
DESCRIPTION
FB
1
I
Feedback pin. Connect to external resistor divider to set output voltage.
GND
2
G
Signal and power ground pin. Place the bottom resistor of the feedback network as close as
possible to this pin.
SW
3
O
Output switch. Connect to the inductor and catch diode.
VIND
4
I/P
Power Input supply.
VINA
5
I/P
Control circuitry supply voltage. Connect VINA to VIND on PC board.
EN
6
I
Enable control input. Logic high enables operation. Do not allow this pin to float or be greater
than VINA + 0.3V.
Die Attach
Pad
–
–
Connect to system ground for low thermal impedance, but it cannot be used as a primary
GND connection.
(1)
I: Input Pin, O: Output Pin, P: Power Pin, G: Ground Pin
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SNVS454E – AUGUST 2006 – REVISED DECEMBER 2014
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6 Specifications
6.1 Absolute Maximum Ratings (1) (2)
MIN
MAX
UNIT
VIN
–0.5
7
V
FB Voltage
–0.5
3
V
EN Voltage
–0.5
7
V
SW Voltage
–0.5
Junction Temperature (3)
Tstg
(1)
(2)
(3)
Storage temperature
–65
7
V
150
°C
150
°C
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.
Thermal shutdown will occur if the junction temperature exceeds the maximum junction temperature of the device.
6.2 ESD Ratings: LM2830
VALUE
V(ESD)
(1)
(2)
Electrostatic discharge
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins (1)
±2000
Charged device model (CDM), per JEDEC specification JESD22-C101, all
pins (2)
±1000
UNIT
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 ESD Ratings: LM2830-Q1
VALUE
Human body model (HBM), per AEC Q100-002 (1)
V(ESD)
(1)
Electrostatic discharge
Charged device model (CDM), per
AEC Q100-011
UNIT
±2000
WSON corner pins (1, 3, 4, and 6)
±1000
SOT-23 corner pins (1, 3, 4, and 5)
±1000
Other pins
±1000
V
AEC Q100-002 indicates HBM stressing is done in accordance with the ANSI/ESDA/JEDEC JS-001 specification.
6.4 Recommended Operating Conditions
MIN
VIN
Junction Temperature
NOM
MAX UNIT
3
5.5
V
–40
125
°C
6.5 Thermal Information
THERMAL METRIC (1)
LM2830,
LM2830-Q1
LM2830
DBV
NGG
5 PINS
6 PINS
RθJA
Junction-to-ambient thermal resistance
165.2
53.9
RθJC(top)
Junction-to-case (top) thermal resistance
69.9
51.2
RθJB
Junction-to-board thermal resistance
27.3
28.2
ψJT
Junction-to-top characterization parameter
1.8
0.6
ψJB
Junction-to-board characterization parameter
26.8
28.3
RθJC(bot)
Junction-to-case (bottom) thermal resistance
N/A
8.1
(1)
4
UNIT
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
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6.6 Electrical Characteristics
VIN = 5 V unless otherwise indicated. Typical values correspond to TJ = 25°C. Minimum and maximum limits apply over
–40°C to 125°C junction temperature range unless otherwise stated.
PARAMETER
TEST CONDITIONS
VFB
Feedback Voltage
WSON and SOT-23 Package
ΔVFB/VIN
Feedback Voltage Line Regulation
VIN = 3 V to 5 V
IB
Feedback Input Bias Current
UVLO
MIN
TYP
MAX
UNIT
0.588
0.600
0.612
V
0.02
VIN Rising
Undervoltage Lockout
Switching Frequency
DMAX
Maximum Duty Cycle
DMIN
Switch On Resistance
ICL
Switch Current Limit
VEN_TH
V
1.85
LM2830-X
1.2
1.6
1.95
LM2830-Z
2.25
3.0
3.75
LM2830-X
86%
94%
LM2830-Z
82%
90%
LM2830-X
2.3
7%
WSON Package
150
SOT-23 Package
130
VIN = 3.3 V
IEN
Enable Pin Current
1.2
195
1.75
0.4
100
Quiescent Current (shutdown)
mΩ
A
1.8
Quiescent Current (switching)
MHz
5%
LM2830-Z
Enable Threshold Voltage
Switch Leakage
TSD
2.90
Shutdown Threshold Voltage
ISW
IQ
nA
2.73
0.43
Minimum Duty Cycle
RDS(ON)
100
VIN Falling
UVLO Hysteresis
FSW
%/V
0.1
V
nA
Sink/Source
100
LM2830X VFB = 0.55
3.3
5
mA
LM2830Z VFB = 0.55
4.3
6.5
mA
All Options VEN = 0 V
Thermal Shutdown Temperature
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nA
30
nA
165
°C
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6.7 Typical Characteristics
All curves taken at VIN = 5.0 V with configuration in typical application circuit shown in Application Information section of this
data sheet. TJ = 25°C, unless otherwise specified.
6
Figure 1. η vs Load "X" Vin = 5 V, Vo = 1.8 V and 3.3 V
Figure 2. η vs Load "Z" Vin = 5 V, Vo = 3.3 V and 1.8 V
Figure 3. η vs Load "X and Z" Vin = 3.3 V, Vo = 1.8 V
Figure 4. Load Regulation Vin = 3.3 V, Vo = 1.8 V (All
Options)
Figure 5. Load Regulation Vin = 5 V, Vo = 1.8 V (All Options)
Figure 6. Load Regulation Vin = 5 V, Vo = 3.3 V (All Options)
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Typical Characteristics (continued)
All curves taken at VIN = 5.0 V with configuration in typical application circuit shown in Application Information section of this
data sheet. TJ = 25°C, unless otherwise specified.
3.45
OSCILLATOR FREQUENCY (MHz)
OSCILLATOR FREQUENCY (MHz)
1.81
1.76
1.71
1.66
1.61
1.56
1.51
1.46
1.41
1.36
-45 -40
-10
20
50
3.35
3.25
3.15
3.05
2.95
2.85
2.75
2.65
2.55
-45 -40
80 110 125 130
-10
20
50
80 110 125 130
TEMPERATURE (ºC)
TEMPERATURE (ºC)
Figure 7. Oscillator Frequency vs Temperature - "X"
Figure 8. Oscillator Frequency vs Temperature - "Z"
2000
1950
CURRENT LIMIT (mA)
1900
1850
1800
1750
1700
1650
1600
1550
1500
-45 -40
-10
20
50
80 110 125 130
TEMPERATURE (oC)
Figure 9. Current Limit vs Temperature Vin = 3.3 V
Figure 10. RDSON vs Temperature (WSON Package)
3.6
3.5
IQ (mA)
3.4
3.3
3.2
3.1
3.0
-45
-40 -10
20
50
80
110 125 130
TEMPERATURE (ºC)
Figure 11. RDSON vs Temperature (SOT-23 Package)
Figure 12. LM2830X IQ (Quiescent Current)
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Typical Characteristics (continued)
All curves taken at VIN = 5.0 V with configuration in typical application circuit shown in Application Information section of this
data sheet. TJ = 25°C, unless otherwise specified.
4.6
4.5
IQ (mA)
4.4
4.3
4.2
4.1
4.0
-45
-40 -10
20
50
80
110 125 130
TEMPERATURE (ºC)
Figure 13. LM2830Z IQ (Quiescent Current)
Figure 14. Line Regulation Vo = 1.8 V, Io = 500 mA
FEEBACK VOLTAGE (V)
0.610
0.605
0.600
0.595
0.590
-45 -40 -10
20
50
80
110 125 130
TEMPERATURE (ºC)
Figure 15. VFB vs Temperature
Figure 16. Gain vs Frequency (Vin = 5 V, Vo = 1.2 V at 1 A)
Figure 17. Phase Plot vs Frequency (Vin = 5 V, Vo = 1.2 V at 1 A)
8
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7 Detailed Description
7.1 Overview
The LM2830 device is a constant frequency PWM buck regulator IC that delivers a 1.0-A load current. The
regulator has a preset switching frequency of 1.6 MHz or 3.0 MHz. This high frequency allows the LM2830
device to operate with small surface-mount capacitors and inductors, resulting in a DC-DC converter that
requires a minimum amount of board space. The LM2830 device is internally compensated, so it is simple to use
and requires few external components. The LM2830 device uses current-mode control to regulate the output
voltage.
The following operating description of the LM2830 device will refer to the Simplified Block Diagram (Functional
Block Diagram) and to the waveforms in Figure 18. The LM2830 device supplies a regulated output voltage by
switching the internal PMOS control switch at constant frequency and variable duty cycle. A switching cycle
begins at the falling edge of the reset pulse generated by the internal oscillator. When this pulse goes low, the
output control logic turns on the internal PMOS control switch. During this on-time, the SW pin voltage (VSW)
swings up to approximately VIN, and the inductor current (IL) increases with a linear slope. IL is measured by the
current sense amplifier, which generates an output proportional to the switch current. The sense signal is
summed with the regulator’s corrective ramp and compared to the error amplifier’s output, which is proportional
to the difference between the feedback voltage and VREF. When the PWM comparator output goes high, the
output switch turns off until the next switching cycle begins. During the switch off-time, inductor current
discharges through the Schottky catch diode, which forces the SW pin to swing below ground by the forward
voltage (VD) of the Schottky catch diode. The regulator loop adjusts the duty cycle (D) to maintain a constant
output voltage.
VSW
D = TON/TSW
VIN
SW
Voltage
TOFF
TON
0
VD
IL
t
TSW
IPK
Inductor
Current
0
t
Figure 18. Typical Waveforms
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7.2 Functional Block Diagram
EN
VIN
+
ENABLE and UVLO
ThermalSHDN
I SENSE
-
+
-
I LIMIT
-
1 .15 x VREF
+
OVPSHDN
Ramp Artificial
Control Logic
cv
FB
S
R
R
Q
1.6 MHz
+
I SENSE
PFET
-
+
DRIVER
Internal - Comp
SW
VREF = 0.6V
SOFT - START
Internal - LDO
GND
7.3 Feature Description
7.3.1 Soft-Start
This function forces VOUT to increase at a controlled rate during start up. During soft-start, the error reference
voltage of the amplifier ramps from 0 V to its nominal value of 0.6 V in approximately 600 µs. This forces the
regulator output to ramp up in a controlled fashion, which helps reduce inrush current.
7.3.2 Output Overvoltage Protection
The overvoltage comparator compares the FB pin voltage to a voltage that is 15% higher than the internal
reference VREF. Once the FB pin voltage goes 15% above the internal reference, the internal PMOS control
switch is turned off, which allows the output voltage to decrease toward regulation.
7.3.3 Undervoltage Lockout
Undervoltage lockout (UVLO) prevents the LM2830 device from operating until the input voltage exceeds 2.73 V
(typical). The UVLO threshold has approximately 430 mV of hysteresis, so the part will operate until VIN drops
below 2.3V (typical). Hysteresis prevents the part from turning off during power up if VIN is nonmonotonic.
10
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Feature Description (continued)
7.3.4 Current Limit
The LM2830 device uses cycle-by-cycle current limiting to protect the output switch. During each switching cycle,
a current limit comparator detects if the output switch current exceeds 1.75 A (typical), and turns off the switch
until the next switching cycle begins.
7.3.5 Thermal Shutdown
Thermal shutdown limits total power dissipation by turning off the output switch when the IC junction temperature
exceeds 165°C. After thermal shutdown occurs, the output switch does not turn on until the junction temperature
drops to approximately 150°C.
7.4 Device Functional Modes
In normal operational mode, the device will regulate output voltage to the value set with resistive divider.
In addition, this device has an enable (EN) pin that lets the user turn the device on and off by driving this pin high
and low. Default setup is that this pin is connected to VIN through pull up resistor (typically 100 kΩ). When enable
pin is low the device is in shutdown mode consuming typically only 30 nA, making it ideal for applications where
low power consumption is desirable.
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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
The device operates with input voltage in the range of 3.3 V to 5.5 V and provide regulated output voltage up to
1 A of continuous DC load. This device is optimized for high efficiency operation with minimum number of
external components. Also, high switching frequency allows use of small surface-mount components enabling
very small solution size. For component selection, see Detailed Design Procedure.
8.2 Typical Applications
8.2.1 LM2830X Design Vo = 1.2 V at 1.0A
FB
EN
LM2830
R3
GND
L1
VIN
VO = 1.2V @ 1.0A
SW
VIN = 5V
R1
C1
D1
C2
R2
Figure 19. LM2830X (1.6 MHz): Vin = 5 V, Vo = 1.2 V at 1.0-A Schematic
8.2.1.1 Design Requirements
This device must be able to operate at any voltage within input voltage range.
Load Current must be defined to properly size the inductor, input and output capacitors. Inductor should be able
to handle full expected load current as well as the peak current generated during load transients and start up.
Inrush current at startup will depend on the output capacitor selection. More details are provided in Detailed
Design Procedure.
Device has an enable (EN) pin that is used to enable and disable the device. This pin is active high and should
not be left floating in application.
8.2.1.2 Detailed Design Procedure
Table 1. Bill of Materials
12
PART ID
PART VALUE
MANUFACTURER
PART NUMBER
U1
1.0-A Buck Regulator
TI
LM2830X
C1, Input Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
C2, Output Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
D1, Catch Diode
0.3 Vf Schottky 1.5 A, 30 VR
TOSHIBA
CRS08
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Typical Applications (continued)
Table 1. Bill of Materials (continued)
PART ID
PART VALUE
MANUFACTURER
PART NUMBER
L1
3.3 µH, 1.3 A
Coilcraft
ME3220-332
R2
15.0 kΩ, 1%
Vishay
CRCW08051502F
R1
15.0 kΩ, 1%
Vishay
CRCW08051502F
R3
100 kΩ, 1%
Vishay
CRCW08051003F
8.2.1.2.1 Inductor Selection
The Duty Cycle (D) can be approximated quickly using the ratio of output voltage (VO) to input voltage (VIN):
D=
VOUT
VIN
(1)
The catch diode (D1) forward voltage drop and the voltage drop across the internal PMOS must be included to
calculate a more accurate duty cycle. Calculate D by using the following formula:
VOUT + VD
D=
VIN + VD - VSW
(2)
VSW can be approximated by:
VSW = IOUT × RDSON
(3)
The diode forward drop (VD) can range from 0.3 V to 0.7 V depending on the quality of the diode. The lower the
VD, the higher the operating efficiency of the converter. The inductor value determines the output ripple current.
Lower inductor values decrease the size of the inductor, but increase the output ripple current. An increase in the
inductor value will decrease the output ripple current.
One must ensure that the minimum current limit (1.2 A) is not exceeded, so the peak current in the inductor must
be calculated. The peak current (ILPK) in the inductor is calculated by:
ILPK = IOUT + ΔiL
(4)
'i L
I OUT
VIN - VOUT
VOUT
L
L
DTS
TS
t
Figure 20. Inductor Current
VIN - VOUT
L
=
2'iL
DTS
(5)
In general,
ΔiL = 0.1 × (IOUT) → 0.2 × (IOUT)
(6)
If ΔiL = 20% of 1 A, the peak current in the inductor will be 1.2 A. The minimum ensured current limit over all
operating conditions is 1.2 A. One can either reduce ΔiL, or make the engineering judgment that zero margin will
be safe enough. The typical current limit is 1.75 A.
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The LM2830 device operates at frequencies allowing the use of ceramic output capacitors without compromising
transient response. Ceramic capacitors allow higher inductor ripple without significantly increasing output ripple.
See the Output Capacitor for more details on calculating output voltage ripple. Now that the ripple current is
determined, the inductance is calculated by:
DTS
x (VIN - VOUT)
L=
2'iL
where
•
Ts = 1/fs
(7)
When selecting an inductor, make sure that it is capable of supporting the peak output current without saturating.
Inductor saturation will result in a sudden reduction in inductance and prevent the regulator from operating
correctly. Because of the speed of the internal current limit, it is necessary to specify the peak current of the
inductor only required maximum output current. For example, if the designed maximum output current is 1.0 A
and the peak current is 1.25 A, then the inductor should be specified with a saturation current limit of > 1.25 A.
There is no need to specify the saturation or peak current of the inductor at the 1.75-A typical switch current limit.
The difference in inductor size is a factor of 5. Because of the operating frequency of the LM2830 device, ferrite
based inductors are preferred to minimize core losses. This presents little restriction because the variety of
ferrite-based inductors is huge. Lastly, inductors with lower series resistance (RDCR) will provide better operating
efficiency.
8.2.1.2.2 Input Capacitor
An input capacitor is necessary to ensure that VIN does not drop excessively during switching transients. The
primary specifications of the input capacitor are capacitance, voltage, RMS current rating, and ESL (Equivalent
Series Inductance). The recommended input capacitance is 22 µF. The input voltage rating is specifically stated
by the capacitor manufacturer. Make sure to check any recommended deratings and also verify if there is any
significant change in capacitance at the operating input voltage and the operating temperature. The input
capacitor maximum RMS input current rating (IRMS-IN) must be greater than:
IRMS_IN D IOUT2 (1-D) +
'i2
3
(8)
Neglecting inductor ripple simplifies the above equation to:
IRMS_IN = IOUT x D(1 - D)
(9)
From Equation 9, it can be shown that maximum RMS capacitor current occurs when D = 0.5. Always calculate
the RMS at the point where the duty cycle D is closest to 0.5. The ESL of an input capacitor is usually
determined by the effective cross sectional area of the current path. A large leaded capacitor will have high ESL
and a 0805 ceramic chip capacitor will have very low ESL. At the operating frequencies of the LM2830 device,
leaded capacitors may have an ESL so large that the resulting impedance (2πfL) will be higher than that required
to provide stable operation. As a result, surface-mount capacitors are strongly recommended.
Sanyo POSCAP, Tantalum or Niobium, Panasonic SP, and multilayer ceramic capacitors (MLCC) are all good
choices for both input and output capacitors and have very low ESL. For MLCCs it is recommended to use X7R
or X5R type capacitors due to their tolerance and temperature characteristics. Consult the capacitor
manufacturer data sheets to see how rated capacitance varies over operating conditions.
8.2.1.2.3 Output Capacitor
The output capacitor is selected based upon the desired output ripple and transient response. The initial current
of a load transient is provided mainly by the output capacitor. The output ripple of the converter is:
1
'VOUT = 'IL RESR +
8 x FSW x COUT
(10)
When using MLCCs, the ESR is typically so low that the capacitive ripple may dominate. When this occurs, the
output ripple will be approximately sinusoidal and 90° phase shifted from the switching action. Given the
availability and quality of MLCCs and the expected output voltage of designs using the LM2830 device, there is
really no need to review any other capacitor technologies. Another benefit of ceramic capacitors is their ability to
bypass high frequency noise. A certain amount of switching edge noise will couple through parasitic
14
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capacitances in the inductor to the output. A ceramic capacitor will bypass this noise while a tantalum will not.
Because the output capacitor is one of the two external components that control the stability of the regulator
control loop, most applications will require a minimum of 22 µF of output capacitance. Capacitance often, but not
always, can be increased significantly with little detriment to the regulator stability. Like the input capacitor,
recommended multilayer ceramic capacitors are X7R or X5R types.
8.2.1.2.4 Catch Diode
The catch diode (D1) conducts during the switch off-time. A Schottky diode is recommended for its fast switching
times and low forward voltage drop. The catch diode should be chosen so that its current rating is greater than:
ID1 = IOUT × (1-D)
(11)
The reverse breakdown rating of the diode must be at least the maximum input voltage plus appropriate margin.
To improve efficiency, choose a Schottky diode with a low forward voltage drop.
8.2.1.2.5 Output Voltage
The output voltage is set using Equation 12, where R2 is connected between the FB pin and GND, and R1 is
connected between VO and the FB pin. A good value for R2 is 10 kΩ. When designing a unity gain converter (Vo
= 0.6 V), R1 should be between 0 Ω and 100 Ω, and R2 should be equal or greater than 10 kΩ.
VOUT
- 1 x R2
R1 =
VREF
(12)
VREF = 0.60 V
(13)
8.2.1.2.6 Calculating Efficiency, and Junction Temperature
The complete LM2830 DC-DC converter efficiency can be calculated in the following manner.
K=
POUT
PIN
(14)
Or
K=
POUT
POUT + PLOSS
(15)
Calculations for determining the most significant power losses are shown below. Other losses totaling less than
2% are not discussed.
Power loss (PLOSS) is the sum of two basic types of losses in the converter: switching and conduction.
Conduction losses usually dominate at higher output loads, whereas switching losses remain relatively fixed and
dominate at lower output loads. The first step in determining the losses is to calculate the duty cycle (D):
D=
VOUT + VD
VIN + VD - VSW
(16)
VSW is the voltage drop across the internal PFET when it is on, and is equal to:
VSW = IOUT × RDSON
(17)
VD is the forward voltage drop across the Schottky catch diode. It can be obtained from the diode manufacturer's
Electrical Characteristics section. If the voltage drop across the inductor (VDCR) is accounted for, the equation
becomes:
D=
VOUT + VD + VDCR
VIN + VD + VDCR - VSW
(18)
The conduction losses in the free-wheeling Schottky diode are calculated as follows:
PDIODE = VD × IOUT × (1-D)
(19)
Often this is the single most significant power loss in the circuit. Care should be taken to choose a Schottky
diode that has a low forward voltage drop.
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Another significant external power loss is the conduction loss in the output inductor. The equation can be
simplified to:
PIND = IOUT2 × RDCR
(20)
The conduction loss of the LC2830 device is mainly associated with the internal PFET:
PCOND= (IOUT2 x D) 1 +
'iL
1
x
3
IOUT
2
RDSON
(21)
If the inductor ripple current is fairly small, the conduction losses can be simplified to:
PCOND = IOUT2 × RDSON × D
(22)
Switching losses are also associated with the internal PFET. They occur during the switch on and off transition
periods, where voltages and currents overlap resulting in power loss. The simplest means to determine this loss
is to empirically measuring the rise and fall times (10% to 90%) of the switch at the switch node.
Switching Power Loss is calculated as follows:
PSWR = 1/2(VIN × IOUT × FSW × TRISE)
PSWF = 1/2(VIN × IOUT × FSW × TFALL)
PSW = PSWR + PSWF
(23)
(24)
(25)
Another loss is the power required for operation of the internal circuitry:
PQ = IQ × VIN
(26)
IQ is the quiescent operating current, and is typically around 3.3 mA for the 1.6-MHz frequency option.
Table 2 lists typical application power losses.
Table 2. Power Loss Tabulation
Design Parameter
Value
VIN
5.0 V
VOUT
3.3 V
IOUT
1.0A
Design Parameter
Value
POUT
3.3 W
PDIODE
150 mW
VD
0.45 V
FSW
1.6 MHz
IQ
3.3 mA
PQ
17 mW
TRISE
4 nS
PSWR
6 mW
TFALL
4 nS
PSWF
6 mW
RDS(ON)
150 mΩ
PCOND
100 mW
INDDCR
70 mΩ
PIND
70 mW
D
0.667
PLOSS
345 mW
η
88%
PINTERNAL
125 mW
ΣPCOND + PSW + PDIODE + PIND + PQ = PLOSS
ΣPCOND + PSWF + PSWR + PQ = PINTERNAL
PINTERNAL = 125mW
16
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(28)
(29)
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8.2.1.3 Application Curves
Figure 21 and Figure 22 show start-up waveforms.
Figure 21. VIN = 5.0 V, VOUT = 0.6 V, Iload = 250 mA at 25°C
Figure 22. VIN = 5.0 V, VOUT = 0.9 V, Iload = 1 A at –40°C
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8.2.2 LM2830X Design Vo = 0.6 V at 1.0-A
Figure 23 shows typical application circuit for step-down solution from VIN=5 to VOUT=0.6 V, 1.0-A load current.
FB
EN
GND
LM2830
R3
L1
VIN
VO = 0.6V @ 1.0A
SW
VIN = 5V
R1
C1
D1
C2
R2
Figure 23. LM2830X (1.6 MHz): Vin = 5 V, Vo = 0.6 V at 1.0-A Schematic
Table 3. Bill of Materials
18
PART ID
PART VALUE
MANUFACTURER
U1
1.0-A Buck Regulator
TI
PART NUMBER
LM2830X
C1, Input Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
C3216X5ROJ226M
C2, Output Cap
22 µF, 6.3 V, X5R
TDK
D1, Catch Diode
0.3 Vf Schottky 1.5 A, 30 VR
TOSHIBA
CRS08
L1
3.3 µH, 1.3 A
Coilcraft
ME3220-332
R2
10.0 kΩ, 1%
Vishay
CRCW08051000F
R1
0Ω
R3
100 kΩ, 1%
Vishay
CRCW08051003F
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8.2.3 LM2830X Design Vo = 3.3 V at 1.0-A
Figure 24 shows typical application circuit for step down solution from VIN=5 to VOUT=3.3 V, 1.0-A load current.
FB
EN
LM2830
R3
GND
L1
VIN
VO = 3.3V @ 1.0A
SW
VIN = 5V
R1
C1
D1
C2
R2
Figure 24. LM2830X (1.6 MHz): Vin = 5 V, Vo = 3.3 V at 1.0-A Schematic
Table 4. Bill of Materials
PART ID
PART VALUE
MANUFACTURER
U1
1.0-A Buck Regulator
TI
PART NUMBER
LM2830X
C1, Input Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
C3216X5ROJ226M
C2, Output Cap
22 µF, 6.3 V, X5R
TDK
D1, Catch Diode
0.3 Vf Schottky 1.5 A, 30 VR
TOSHIBA
CRS08
L1
2.2 µH, 1.8 A
Coilcraft
ME3220-222
R2
10.0 kΩ, 1%
Vishay
CRCW08051002F
R1
45.3 kΩ, 1%
Vishay
CRCW08054532F
R3
100 kΩ, 1%
Vishay
CRCW08051003F
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8.2.4 LM2830Z Design Vo = 3.3 V at 1.0-A
Figure 25 shows typical application circuit for step down solution from VIN=5 to VOUT=3.3 V, 1.0-A load current
when using device version with higher switching frequency.
FB
EN
LM2830
R3
GND
L1
VIN
VO = 3.3V @ 1.0A
SW
VIN = 5V
R1
C1
D1
C2
R2
Figure 25. LM2830Z (3 MHz): Vin = 5 V, Vo = 3.3 V at 1.0-A Schematic
Table 5. Bill of Materials
20
PART ID
PART VALUE
MANUFACTURER
U1
1.0-A Buck Regulator
TI
LM2830Z
C1, Input Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
C2, Output Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
D1, Catch Diode
0.3 Vf Schottky 1.5 A, 30VR
TOSHIBA
CRS08
L1
1.6 µH, 2.0 A
TDK
VLCF4018T-1R6N1R7-2
R2
10.0 kΩ, 1%
Vishay
CRCW08051002F
R1
45.3 kΩ, 1%
Vishay
CRCW08054532F
R3
100 kΩ, 1%
Vishay
CRCW08051003F
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PART NUMBER
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8.2.5 LM2830Z Design Vo = 1.2 V at 1.0-A
Figure 26 shows a typical application circuit for step down solution from VIN=5 to VOUT=1.2 V, 1.0-A load current
when using device version with higher switching frequency.
FB
EN
LM2830
R3
GND
L1
VIN
VO = 1.2V @ 1.0A
SW
VIN = 5V
R1
C1
D1
C2
R2
Figure 26. LM2830Z (3 MHz): Vin = 5 V, Vo = 1.2 V at 1.0-A Schematic
Table 6. Bill of Materials
PART ID
PART VALUE
MANUFACTURER
U1
1.0-A Buck Regulator
TI
LM2830Z
C1, Input Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
C2, Output Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
D1, Catch Diode
0.3Vf Schottky 1.5 A, 30VR
TOSHIBA
CRS08
L1
1.6 µH, 2.0 A
TDK
VLCF4018T-1R6N1R7-2
R2
10.0 kΩ, 1%
Vishay
CRCW08051002F
R1
10.0 kΩ, 1%
Vishay
CRCW08051002F
R3
100 kΩ, 1%
Vishay
CRCW08051003F
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PART NUMBER
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8.2.6 LM2830X Dual Converters With Delayed Enabled Design
Figure 27 shows proposed solution with two LM2830 devices. Output of device on top (3.3-V output) is used to
control the enable pin of the lower device, thus ensuring that the second device (1.2-V output) can not turn on
before the output of first device (3.3-V in this example) reaches steady state. Additionally, small POR supervisory
(LP3470) circuit is used to monitor enable voltage for lower device. The RESET pin on POR circuit is open drain
and requires typically 20-kΩ pullup resistor to the monitored voltage.
VIN
U1
C1
VIND
R3
VINA
L1 VO = 3.3V @ 1.0A
SW
R1
EN
LM2830
D1
C2
R2
GND
FB
U3
4
R6
3
LP3470M5X-3.08
LP3470
RESET
5
2
1
VIN
C7
U2
C3
VIND VINA
L2
VO = 1.2V @ 1.0A
SW
R4
LM2830
D2
C4
EN
R5
GND
FB
Figure 27. LM2830X (1.6 MHz): Vin = 5 V, Vo = 1.2 V at 1.0 A and 3.3 V at 1.0-A Schematic
Table 7. Bill of Materials
22
PART ID
PART VALUE
MANUFACTURER
PART NUMBER
U1, U2
1.0-A Buck Regulator
TI
LM2830X
U3
Power on Reset
TI
LP3470M5X-3.08
C1, C3 Input Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
C2, C4 Output Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
C7
Trr delay capacitor
TDK
D1, D2 Catch Diode
0.3 Vf Schottky 1.5 A, 30 VR
TOSHIBA
CRS08
L1, L2
3.3 µH, 1.3 A
Coilcraft
ME3220-332
R2, R4, R5
10.0 kΩ, 1%
Vishay
CRCW08051002F
R1, R6
45.3 kΩ, 1%
Vishay
CRCW08054532F
R3
100 kΩ, 1%
Vishay
CRCW08051003F
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8.2.7 LM2830X Buck Converter and Voltage Double Circuit With LDO Follower
Figure 28 shows an example where the LM2830 device is used to provide regulated output voltage (3.3 V) as
well as input voltage for an LDO, effectively providing solution with two output voltages.
VO = 5V @ 150mA
U2
L2
LDO
D2
C6
U1
C3
LM2830
VIN = 5V
VIND
SW
VINA
GND
C5
C4
L1
R1
C1
VO = 3.3V @ 1.0A
EN
FB
C2
D1
R2
Figure 28. LM2830X (1.6 MHz): Vin = 5 V, Vo = 3.3 V at 1.0 A and LP2986-5.0 at 150-mA Schematic
Table 8. Bill of Materials
PART ID
PART VALUE
MANUFACTURER
PART NUMBER
U1
1.0-A Buck Regulator
TI
LM2830X
U2
200-mA LDO
TI
LP2986-5.0
C1, Input Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
C2, Output Cap
22 µF, 6.3 V, X5R
TDK
C3216X5ROJ226M
C1608X5R0J225M
C3 – C6
2.2 µF, 6.3 V, X5R
TDK
D1, Catch Diode
0.3 Vf Schottky 1.5 A, 30 VR
TOSHIBA
CRS08
D2
0.4 Vf Schottky 20 VR, 500 mA
ON Semi
MBR0520
L2
10 µH, 800 mA
CoilCraft
ME3220-103
L1
3.3 µH, 2.2 A
TDK
VLCF5020T-3R3N2R0-1
R2
45.3 kΩ, 1%
Vishay
CRCW08054532F
R1
10.0 kΩ, 1%
Vishay
CRCW08051002F
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9 Power Supply Recommendations
The LM2830 is designed to operate from an input voltage supply range between 3.0 V and 5.5 V. This input
supply should be able to withstand the maximum input current and maintain a voltage above 3.0 V. If the input
supply is located farther away (more than a few inches) from the LM2830, additional bulk capacitance may be
required in addition to the ceramic bypass capacitors.
10 Layout
10.1 Layout Guidelines
When planning layout there are a few things to consider when trying to achieve a clean, regulated output. The
most important consideration is the close coupling of the GND connections of the input capacitor and the catch
diode D1. These ground ends should be close to one another and be connected to the GND plane with at least
two through-holes. Place these components as close to the IC as possible. Next in importance is the location of
the GND connection of the output capacitor, which should be near the GND connections of CIN and D1.
There should be a continuous ground plane on the bottom layer of a two-layer board except under the switching
node island.
The FB pin is a high-impedance node and care should be taken to make the FB trace short to avoid noise pickup
and inaccurate regulation. The feedback resistors should be placed as close as possible to the IC, with the GND
of R1 placed as close as possible to the GND of the IC. The VOUT trace to R2 should be routed away from the
inductor and any other traces that are switching.
High AC currents flow through the VIN, SW and VOUT traces, so they should be as short and wide as possible.
However, making the traces wide increases radiated noise, so the designer must make this trade-off. Radiated
noise can be decreased by choosing a shielded inductor.
The remaining components should also be placed as close as possible to the IC. See Application Note AN-1229
SNVA054 for further considerations and the LM2830 demo board as an example of a four-layer layout.
10.2 Layout Example
Figure 29. Example Schematic
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Layout Example (continued)
Figure 30. PCB Layout Example
10.3 Thermal Considerations
The PCB size, weight of copper used to route traces and ground plane, and number of layers within the PCB can
greatly effect RθJA. The type and number of thermal vias can also make a large difference in the thermal
impedance. Thermal vias are necessary in most applications. They conduct heat from the surface of the PCB to
the ground plane. Four to six thermal vias should be placed under the exposed pad to the ground plane if the
WSON package is used.
Thermal impedance also depends on the thermal properties of the application operating conditions (Vin, Vo, Io
etc), and the surrounding circuitry.
Silicon Junction Temperature Determination Method 1:
To accurately measure the silicon temperature for a given application, two methods can be used. The first
method requires the user to know the thermal impedance of the silicon junction to top case temperature.
Some clarification needs to be made before we go any further.
RθJC is the thermal impedance from all six sides of an IC package to silicon junction.
RΦJC is the thermal impedance from top case to the silicon junction.
In this data sheet we will use RΦJC so that it allows the user to measure top case temperature with a small
thermocouple attached to the top case.
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Thermal Considerations (continued)
RΦJC is approximately 30°C/Watt for the 6-pin WSON package with the exposed pad. Knowing the internal
dissipation from the efficiency calculation given previously, and the case temperature, which can be empirically
measured on the bench we have:
TJ - TC
R)JC=
Power
(30)
Therefore:
Tj = (RΦJC x PLOSS) + TC
(31)
From the previous example:
Tj = (RΦJC x PINTERNAL) + TC
Tj = 30°C/W x 0.189W + TC
(32)
(33)
The second method can give a very accurate silicon junction temperature.
The first step is to determine RθJA of the application. The LM2830 device has over-temperature protection
circuitry. When the silicon temperature reaches 165°C, the device stops switching. The protection circuitry has a
hysteresis of about 15°C. Once the silicon temperature has decreased to approximately 150°C, the device will
start to switch again. Knowing this, the RθJA for any application can be characterized during the early stages of
the design one may calculate the RθJA by placing the PCB circuit into a thermal chamber. Raise the ambient
temperature in the given working application until the circuit enters thermal shutdown. If the SW-pin is monitored,
it will be obvious when the internal PFET stops switching, indicating a junction temperature of 165°C. Knowing
the internal power dissipation from the above methods, the junction temperature, and the ambient temperature
RθJA can be determined.
RTJA=
165° - Ta
PINTERNAL
(34)
Once this is determined, the maximum ambient temperature allowed for a desired junction temperature can be
found.
An example of calculating RθJA for an application using the Texas Instruments LM2830 WSON demonstration
board is shown below.
The four layer PCB is constructed using FR4 with ½ oz copper traces. The copper ground plane is on the bottom
layer. The ground plane is accessed by two vias. The board measures 3-cm × 3-cm. It was placed in an oven
with no forced airflow. The ambient temperature was raised to 144°C, and at that temperature, the device went
into thermal shutdown.
From the previous example:
PINTERNAL = 189mW
o
RTJA=
(35)
o
165 C - 144 C
= 111o C/W
189 mW
(36)
If the junction temperature was to be kept below 125°C, then the ambient temperature could not go above 109°C
Tj - (RθJA x PLOSS) = TA
125°C - (111°C/W x 189mW) = 104°C
26
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(38)
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10.4 WSON Package
Figure 31. Internal WSON Connection
For certain high-power applications, the PCB land may be modified to a "dog bone" shape (see Figure 32). By
increasing the size of ground plane, and adding thermal vias, the RθJA for the application can be reduced.
FB
GND
6 EN
1
2
GND
PLANE
SW 3
5 VINA
4 VIND
Figure 32. 6-Lead WSON PCB "Dog Bone" Layout
Copyright © 2006–2014, Texas Instruments Incorporated
Product Folder Links: LM2830 LM2830-Q1
Submit Documentation Feedback
27
LM2830, LM2830-Q1
SNVS454E – AUGUST 2006 – REVISED DECEMBER 2014
www.ti.com
11 Device and Documentation Support
11.1 Device Support
11.1.1 Third-Party Products Disclaimer
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT
CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER
ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.
11.1.2 Thermal Definitions
TJ
Chip junction temperature
TA
Ambient temperature
RθJC
Thermal resistance from chip junction to device case
RθJA
Thermal resistance from chip junction to ambient air
Heat in the LM2830 device due to internal power dissipation is removed through conduction and/or convection.
Conduction: Heat transfer occurs through cross sectional areas of material. Depending on the material, the
transfer of heat can be considered to have poor to good thermal conductivity properties (insulator
vs. conductor).
Heat Transfer goes as:
Silicon → package → lead frame → PCB
Convection: Heat transfer is by means of airflow. This could be from a fan or natural convection. Natural
convection occurs when air currents rise from the hot device to cooler air.
Thermal impedance is defined as:
RT=
'T
Power
(39)
Thermal impedance from the silicon junction to the ambient air is defined as:
RTJA=
TJ - TA
Power
(40)
11.2 Related Links
The table below lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to sample or buy.
Table 9. Related Links
PARTS
PRODUCT FOLDER
SAMPLE & BUY
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
LM2830
Click here
Click here
Click here
Click here
Click here
LM2830-Q1
Click here
Click here
Click here
Click here
Click here
11.3 Trademarks
All trademarks are the property of their respective owners.
11.4 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.
28
Submit Documentation Feedback
Copyright © 2006–2014, Texas Instruments Incorporated
Product Folder Links: LM2830 LM2830-Q1
LM2830, LM2830-Q1
www.ti.com
SNVS454E – AUGUST 2006 – REVISED DECEMBER 2014
11.5 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.
Copyright © 2006–2014, Texas Instruments Incorporated
Product Folder Links: LM2830 LM2830-Q1
Submit Documentation Feedback
29
PACKAGE OPTION ADDENDUM
www.ti.com
30-Sep-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)
Device Marking
(3)
(4/5)
(6)
LM2830XMF
NRND
SOT-23
DBV
5
1000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
SKTB
LM2830XMF/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SKTB
LM2830XMFX/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SKTB
LM2830XQMF/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SUFB
LM2830XQMFE/NOPB
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SUFB
LM2830XQMFX/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SUFB
LM2830ZMF/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SKXB
LM2830ZQMF/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SURB
LM2830ZQMFE/NOPB
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SURB
LM2830ZQMFX/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SURB
LM2830ZSD/NOPB
ACTIVE
WSON
NGG
6
1000
RoHS & Green
SN
Level-3-260C-168 HR
-40 to 125
L192B
(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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