TI LM34922 28v, 2a constant on-time switching regulator with adjustable current limit Datasheet

LM34922
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LM34922 28V, 2A Constant On-Time Switching Regulator with Adjustable Current Limit
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FEATURES
1
•
•
•
•
2
•
•
•
•
•
•
Input Operating Voltage Range: 6V to 28V
Absolute Maximum Input Rating: 30V
Integrated 2A N-Channel Buck Switch
Adjustable Current Limit Allows for Smaller
Inductor
Adjustable Output Voltage from 2.51V
Minimum Ripple Voltage at VOUT
Power Good Output
Switching Frequency Adjustable to 1MHz
COT Topology Features:
– Switching Frequency Remains Nearly
Constant with Load Current and Input
Voltage Variations
– Ultra-Fast Transient Response
– No Loop Compensation Required
– Stable Operation with Ceramic Output
Capacitors
– Allows for Smaller Output Capacitor and
Current Sense Resistor
Adjustable Soft-Start Timing
•
•
Thermal Shutdown
Precision 2% Feedback Reference
DESCRIPTION
The LM34922 Constant On-time Step-Down
Switching Regulator features all the functions needed
to implement a low cost, efficient, buck bias regulator
capable of supplying up to 2A of load current. This
voltage regulator contains an N-Channel Buck switch,
a startup regulator, current limit detection, and
internal ripple control. The constant on-time
regulation principle requires no loop compensation,
results in fast load transient response, and simplifies
circuit implementation. The operating frequency
remains constant with line and load. The adjustable
valley current limit detection results in a smooth
transition from constant voltage to constant current
mode when current limit is reached, without the use
of current limit foldback. The PGD output indicates
the output voltage has increased to within 5% of the
expected regulation value. Additional features
include: Low output ripple, VIN under-voltage lockout, adjustable soft-start timing, thermal shutdown,
gate drive pre-charge, gate drive under-voltage lockout, and maximum duty cycle limit.
Typical Application, Basic Step-Down Regulator
6V to 28V
Input
VIN
BST
CBST
LM34922
CIN
RT
SW
D1
RT
VOUT
CS
RPGD
VPGD
Power
Good
L1
RS
PGD
CSG
COUT
RFB2
SS
CSS
SGND
FB
RFB1
1
2
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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LM34922
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Connection Diagram
Exposed Pad on Bottom
Connect to Ground
VIN
1
10
BST
RT
2
9
SW
PGD
3
8
CS
SS
4
7
CSG
SGND
5
6
FB
Figure 1. Top View
10-Lead HVSSOP-PowerPAD
PIN DESCRIPTIONS
Pin No.
Name
Description
1
VIN
Input supply voltage
Application Information
2
RT
On-time Control
An external resistor from VIN to this pin sets the buck switch on-time, and the
switching frequency.
3
PGD
Power Good
Logic output indicates when the voltage at the FB pin has increased to above
95% of the internal reference voltage. Hysteresis is provided. An external
pull-up resistor to a voltage less than 7V is required.
4
SS
Soft-Start
5
SGND
Signal Ground
6
FB
Feedback
Internally connected to the regulation comparator. The regulation level is
2.51V.
7
CSG
Current Sense Ground
Ground connection for the current limit sensing circuit. Connect to ground
and to the current sense resistor.
8
CS
Current sense
Connect to the current sense resistor and the anode of the free-wheeling
diode.
9
SW
Switching Node
10
BST
Bootstrap capacitor connection of the
buck switch gate driver.
Operating input range is 6V to 28V. Transient capability is 30V. A low ESR
capacitor must be placed as close as possible to the VIN and SGND pins.
An internal current source charges an external capacitor to provide the softstart function.
Ground for all internal circuitry other than the current limit sense circuit.
Internally connected to the buck switch source. Connect to the external
inductor, cathode of the free-wheeling diode, and bootstrap capacitor.
Connect a 0.1µF capacitor from SW to this pin. The capacitor is charged
during the buck switch off-time via an internal diode.
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.
2
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Absolute Maximum Ratings
(1) (2) (3)
VIN to SGND (TJ = 25°C)
30V
BST to SGND
37V
SW to SGND (Steady State)
-1.5V to 30V
BST to SW
-0.3V to 7V
CS to CSG
-0.3V to 0.3V
CSG to SGND
-0.3V to 0.3V
PGD to SGND
-0.3V to 7V
SS to SGND
-0.3V to 3V
RT to SGND
-0.3V to 1V
FB to SGND
-0.3V to 7V
ESD Rating
(4)
Human Body Model
2kV
Storage Temperature Range
-65°C to +150°C
For soldering specs see: SNOA549C
Junction Temperature
(1)
(2)
(3)
(4)
150°C
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 specifications and test conditions, see the Electrical Characteristics.
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
Current flow out of a pin is indicated as a negative number.
The human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin.
Operating Ratings
(1)
VIN Voltage
6.0V to 28V
Junction Temperature
(1)
–40°C to +125°C
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 specifications and test conditions, see the Electrical Characteristics.
Electrical Charateristics
Specifications with standard type are for TJ = 25°C only; limits in boldface type apply over the full Operating Junction
Temperature (TJ) range. Minimum and Maximum limits are specified through test, design, or statistical correlation. Typical
values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless
otherwise stated the following conditions apply: VIN = 12V, RT = 50kΩ.
Symbol
Parameter
Conditions
Input operating current
Non-switching, FB = 3V
VIN under-voltage lock-out threshold
VIN Increasing
Min
Typ
Max
Units
1200
1600
µA
5.3
5.9
V
Input (VIN Pin)
IIN
UVLOVIN
4.6
VIN under-voltage lock-out threshold
hysteresis
200
mV
Switch Characteristics
RDS(ON)
Buck Switch RDS(ON)
ITEST = 200mA
UVLOGD
Gate Drive UVLO
BST-SW
2.4
UVLOGD Hysteresis
Pre-charge switch voltage
0.3
0.6
3.4
4.4
350
ITEST = 10mA into SW pin
Ω
V
mV
1.4
V
Pre-charge switch on-time
120
ns
VSS
Pull-up voltage
2.51
V
ISS
Internal current source
Soft-Start Pin
VSS-SH
Shutdown Threshold
70
10
µA
140
mV
Current Limit
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Electrical Charateristics (continued)
Specifications with standard type are for TJ = 25°C only; limits in boldface type apply over the full Operating Junction
Temperature (TJ) range. Minimum and Maximum limits are specified through test, design, or statistical correlation. Typical
values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless
otherwise stated the following conditions apply: VIN = 12V, RT = 50kΩ.
Symbol
VILIM
Parameter
Conditions
Threshold voltage at CS
Min
Typ
Max
Units
-146
-130
-115
mV
CS bias current
FB = 3V
-120
µA
CSG bias current
FB = 3V
-35
µA
tON - 1
On-time
VIN = 12V, RT = 50kΩ
tON - 2
On-time (current limit)
VIN = 12V, RT = 50kΩ
tON - 3
On-time
VIN = 12V, RT = 301kΩ
tON - 4
On-time
VIN = 9V, RT = 30.9kΩ
130
171
215
ns
tON - 5
On-time
VIN = 12V, RT = 30.9kΩ
105
137
170
ns
tON - 6
On-time
VIN = 16V, RT = 30.9kΩ
79
109
142
ns
90
150
208
ns
2.46
2.51
2.56
On Timer, RT Pin
150
200
250
100
ns
ns
1020
ns
Off Timer
tOFF
Minimum Off-time (LM34922)
Regulation Comparator (FB Pin)
VREF
FB regulation threshold
SS pin = steady state
FB bias current
FB = 3V
V
100
nA
95
%
Power Good (PGD pin)
Threshold at FB, with respect to VREF
FB increasing
91
Threshold hysteresis
3.3
%
PGDVOL
Low state voltage
IPGD = 1mA, FB = 0V
125
180
mV
PGDLKG
Off state leakage
VPGD = 7V, FB = 3V
0.1
µA
Thermal shutdown
Junction temperature increasing
155
°C
20
°C
48
°C/W
10
°C/W
Thermal Shutdown
TSD
Thermal shutdown hysteresis
Thermal Resistance
(1)
4
θJA
Junction to Ambient, 0 LFPM Air Flow
θJC
(1)
Junction to Case,
(1)
JEDEC test board description can be found in JESD 51-5 and JESD 51-7.
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Typical Performance Characteristics
Efficiency (Circuit of Figure 19)
On-Time
vs
VIN and RT
10000
RT = 500k
ON-TIME (ns)
300k
1000
50k
100
100k
200k
10
0
5
10
15
20
25
30
VIN (V)
Figure 2.
Figure 3.
Voltage at the RT Pin
Shutdown Current into VIN
Figure 4.
Figure 5.
Operating Current into VIN
PGD Low Voltage
vs.
Sink Current
Figure 6.
Figure 7.
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Typical Performance Characteristics (continued)
6
Reference Voltage
vs.
Temperature
Current Limit Threshold
vs.
Temperature
Figure 8.
Figure 9.
Operating Current
vs.
Temperature
VIN UVLO
vs.
Temperature
Figure 10.
Figure 11.
SS Pin ShutdownThreshold
vs.
Temperature
On-Time
vs.
Temperature
Figure 12.
Figure 13.
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Typical Performance Characteristics (continued)
Minimum Off-Time
vs.
Temperature (LM34922)
Figure 14.
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Block Diagram
6V to 28V
LM34922
VIN
5V REGULATOR
Input
CIN
CBYP
UVLO
CL
RT
THERMAL
SHUTDOWN
OFF TIMER
ON TIMER
RT
FINISH
START
START
FINISH
BST
2.5V
Gate Drive
10
PA
SD
UVLO
VIN
CBST
SS
LOGIC
CSS
LEVEL
SHIFT
L1
+
FB
CL
REGULATION
COMPARATOR
VOUT
SW
FCIC
CONTROL
CURRENT
LIMIT COMPARATOR
D1
+
COUT
Pre - Chg
-
RFB2
CS
RPGD
Power
Good
0.8V
PGD
CURRENT LIMIT
THRESHOLD
SGND
+
+
125 mV
RS
CSG
2.375V
RFB2
WHITE SPACE
UVLO
VIN
SW Pin
Inductor
Current
SS Pin
VOUT
PGD
t1
Figure 15. Startup Sequence
8
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FUNCTIONAL DESCRIPTION
The LM34922 Constant On-time Step-down Switching Regulator features all the functions needed to implement a
low cost, efficient buck bias power converter capable of supplying up to 2.0A to the load. This high voltage
regulator contains an N-Channel buck switch, is easy to implement, and is available in a 10-pin HVSSOPPowerPAD power enhanced package. The regulator’s operation is based on a constant on-time control principle
with the on-time inversely proportional to the input voltage. This feature results in the operating frequency
remaining relatively constant with load and input voltage variations. The constant on-time feedback control
principle requires no loop compensation resulting in very fast load transient response. The adjustable valley
current limit detection results in a smooth transition from constant voltage to constant current when current limit is
reached. To aid in controlling excessive switch current due to a possible saturating inductor the on-time is
reduced by ≊40% when current limit is detected. The Power Good output (PGD pin) indicates when the output
voltage is within 5% of the expected regulation voltage.
The LM34922 can be implemented to efficiently step-down higher voltages in non-isolated applications.
Additional features include: Low output ripple, VIN under-voltage lock-out, adjustable soft-start timing, thermal
shutdown, gate drive pre-charge, gate drive under-voltage lock-out, and maximum duty cycle limit.
Control Circuit Overview
The LM34922 buck regulator employs a control principle based on a comparator and a one-shot on-timer, with
the output voltage feedback (FB) compared to an internal reference (2.51V). If the FB voltage is below the
reference the internal buck switch is switched on for the one-shot timer period, which is a function of the input
voltage and the programming resistor (RT). Following the on-time the switch remains off until the FB voltage falls
below the reference, but never less than the minimum off-time forced by the off-time one-shot timer. When the
FB pin voltage falls below the reference and the off-time one-shot period expires, the buck switch is then turned
on for another on-time one-shot period.
When in regulation, the LM34922 operates in continuous conduction mode at heavy load currents and
discontinuous conduction mode at light load currents. In continuous conduction mode the inductor’s current is
always greater than zero, and the operating frequency remains relatively constant with load and line variations.
The minimum load current for continuous conduction mode is one-half the inductor’s ripple current amplitude.
The approximate operating frequency is calculated as follows:
VOUT
FS =
-11
(4.1 x 10 x (RT + 0.5k)) + (VIN x 15 ns)
(1)
The buck switch duty cycle is approximately equal to:
DC =
tON
VOUT
= tON x FS =
tON + tOFF
VIN
(2)
When the load current is less than one half the inductor’s ripple current amplitude the circuit operates in
discontinuous conduction mode. The off-time is longer than in continuous conduction mode while the inductor
current is zero, causing the switching frequency to reduce as the load current is reduced. Conversion efficiency is
maintained at light loads since the switching losses are reduced with the reduction in load and frequency. The
approximate discontinuous operating frequency can be calculated as follows:
FS =
VOUT2 x L1 x 1.19 x 1021
2
RL x R T
where
•
•
RL = the load resistance
L1 is the circuit’s inductor
(3)
The output voltage is set by the two feedback resistors (RFB1, RFB2 in the Block Diagram). The regulated output
voltage is calculated as follows:
VOUT = 2.51V x (RFB1 + RFB2) / RFB1
(4)
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Ripple voltage, which is required at the input of the regulation comparator for proper output regulation, is
generated internally in the LM34922. In the LM34922 the ERM (Emulated Ripple Mode) control circuit generates
the required internal ripple voltage from the ripple waveform at the CS pin.
On-Time Timer
The on-time for the LM34922 is determined by the RT resistor and the input voltage (VIN), calculated from:
tON =
4.1 x 10
-11
x (RT + 500:)
(VIN)
+ 15 ns
(5)
The inverse relationship with VIN results in a nearly constant frequency as VIN is varied. To set a specific
continuous conduction mode switching frequency (FS), the RT resistor is determined from the following:
VOUT - (VIN x FS x 15 ns)
- 500:
RT =
-11
FS x 4.1 x 10
(6)
The on-time must be chosen greater than 90ns for proper operation. Equation 1, Equation 5 and Equation 6 are
valid only during normal operation - i.e., the circuit is not in current limit. When the LM34922 operates in current
limit, the on-time is reduced by ≊40%. This feature reduces the peak inductor current which may be excessively
high if the load current and the input voltage are simultaneously high. This feature operates on a cycle-by-cycle
basis until the load current is reduced and the output voltage resumes its normal regulated value. The maximum
continuous current into the RT pin must be less than 2mA. For high frequency applications, the maximum
switching frequency is limited at the maximum input voltage by the minimum on-time one-shot period (90ns). At
minimum input voltage the maximum switching frequency is limited by the minimum off-time one-shot period,
which, if reached, prevents achievement of the proper duty cycle.
Current Limit
Current limit detection occurs during the off-time by monitoring the voltage across the external current sense
resistor RS. Referring to the Block Diagram, during the off-time the recirculating current flows through the
inductor, through the load, through the sense resistor, and through D1 to the inductor. If the voltage across the
sense resistor exceeds the threshold (VILIM) the current limit comparator output switches to delay the start of the
next on-time period. The next on-time starts when the recirculating current decreases such that the voltage
across RS reduces to the threshold and the voltage at FB is below 2.51V. The operating frequency is typically
lower due to longer-than-normal off-times. When current limit is detected, the on-time is reduced by ≊40% if the
voltage at the FB pin is below its threshold when the voltage across RS reduces to its threshold (VOUT is low due
to current limiting).
Figure 16 illustrates the inductor current waveform during normal operation and in current limit. During the first
“Normal Operation” the load current is I01, the average of the inductor current waveform. As the load resistance is
reduced, the inductor current increases until the lower peak of the inductor ripple current exceeds the threshold.
During the “Current Limited” portion of Figure 16, each on-time is reduced by ≊40%, resulting in lower ripple
amplitude for the inductor’s current. During this time the LM34922 is in a constant current mode with an average
load current equal to the current limit threshold plus half the ripple amplitude (IOCL), and the output voltage is
below the normal regulated value. Normal operation resumes when the load current is reduced (to IO2), allowing
VOUT and the on-time to return to their normal values. Note that in the second period of “Normal Operation”, even
though the inductor’s peak current exceeds the current limit threshold during part of each cycle, the circuit is not
in current limit since the inductor current falls below the current limit threshold during each off time. The peak
current allowed through the buck switch is 3.5A, and the maximum allowed average current is 2.0A.
10
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IPK
IOCL
Current
Limit Threshold
IO2
'I
Inductor
Current
IO1
0V
Voltage at the CS Pin
Voltage at the FB Pin
2.51V
Load
Current
Increases
Normal
Operation
Current
Limited
Load Current
Decreases
Normal
Operation
Figure 16. Normal and Current Limit Operation
Ripple Requirements
The LM34922 requires a minimum of 15mVp-p ripple voltage at the CS pin. That ripple voltage is generated by
the decreasing recirculating current (the inductor’s ripple current) through RS during the off-time. See Figure 17.
Inductor
Current
'I
0V
Voltage
at CS
VRIPPLE
tON
tOFF
(3a)
Figure 17. CS Pin Waveform
The ripple voltage is equal to:
VRIPPLE = ΔI x RS
where
•
•
ΔI is the inductor current ripple amplitude
RS is the current sense resistor at the CS pin
(7)
N-Channel Buck Switch and Driver
The LM34922 integrates an N-Channel buck switch and associated floating high voltage gate driver. The gate
driver circuit works in conjunction with an external bootstrap capacitor (CBST) and an internal high voltage diode.
A 0.1µF capacitor connected between BST and SW provides the supply voltage for the driver during the on-time.
During each off-time, the SW pin is at approximately -1V, and CBST is recharged from the internal 5V regulator for
the next on-time. The minimum off-time ensures a sufficient time each cycle to recharge the bootstrap capacitor.
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Soft-Start
The soft-start feature allows the converter to gradually reach a steady state operating point, thereby reducing
startup stresses and current surges. Upon turn-on, when VIN reaches its under-voltage lock-out threshold an
internal 10µA current source charges the external capacitor at the SS pin to 2.51V (t1 in Figure 15). The ramping
voltage at SS ramps the non-inverting input of the regulation comparator, and the output voltage, in a controlled
manner. For proper operation, the soft-start capacitor should be no smaller than 1000pF.
The LM34922 can be employed as a tracking regulator by applying the controlling voltage to the SS pin. The
regulator’s output voltage tracks the applied voltage, gained up by the ratio of the feedback resistors. The applied
voltage at the SS pin must be within the range of 0.5V to 2.6V. The absolute maximum rating for the SS pin is
3.0V. If the tracking function causes the voltage at the FB pin to go below the thresholds for the PGD pin, the
PGD pin will switch low (see the Power Good Output (PGD) section). An internal switch grounds the SS pin if the
input voltage at VIN is below its under-voltage lock-out threshold or if the Thermal Shutdown activates. If the
tracking function (described above) is used, the tracking voltage applied to the SS pin must be current limited to
a maximum of 1mA.
Shutdown Function
The SS pin can be used to shutdown the LM34922 by grounding the SS pin as shown in Figure 18. Releasing
the pin allows normal operation to resume.
SS
STOP
LM34922
CSS
RUN
Figure 18. Shutdown Implemetation
Power Good Output (PGD)
The Power Good output (PGD) indicates when the voltage at the FB pin is close to the internal 2.51V reference
voltage. The rising threshold at the FB pin for the PGD output to switch high is 95% of the internal reference. The
falling threshold for the PGD output to switch low is approximately 3.3% below the rising threshold.
The PGD pin is internally connected to the drain of an N-channel MOSFET switch. An external pull-up resistor
(RPGD), connected to an appropriate voltage not exceeding 7V, is required at PGD to indicate the LM34922’s
status to other circuitry. When PGD is low, the pin’s voltage is determined by the current into the pin. See the
graph “ PGD Low Voltage vs. Sink Current”.
Upon powering up the LM34922, the PGD pin is high until the voltage at VIN reaches 2V, at which time PGD
switches low. As VIN is increased PGD stays low until the output voltage takes the voltage at the FB pin above
95% of the internal reference voltage, at which time PGD switches high. As VIN is decreased (during shutdown)
PGD remains high until either the voltage at the FB pin falls below ≊92% of the internal reference, or when VIN
falls below its lower UVLO threshold, whichever occurs first. PGD then switches low, and remains low until VIN
falls below 2V, at which time PGD switches high. If the LM34922 is used as a tracking regulator (see the SoftStart section), the PGD output is high as long as the voltage at the FB pin is above the thresholds mentioned
above.
Thermal Shutdown
The LM34922 should be operated so the junction temperature does not exceed 125°C. If the junction
temperature increases above that, an internal Thermal Shutdown circuit activates (typically) at 155°C, taking the
controller to a low power reset state by disabling the buck switch and taking the SS pin to ground. This feature
helps prevent catastrophic failures from accidental device overheating. When the junction temperature reduces
below 135°C (typical hysteresis = 20°C) normal operation resumes.
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8V to 28V
Input
RT
118 k:
CIN
4.7 PF
CBYP
0.1 PF
BST
VIN
CBST 0.1 PF
L1 10 PH
LM34922
SW
RT
VOUT
D1
5V
VPGD
CS
RPGD
10 k:
Power
Good
COUT
10 PF
RS
80 m:
PGD
CSG
RFB2
4.99 k:
SS
CSS
0.022 PF
SGND
FB
RFB1
4.99 k:
Figure 19. Example Circuit
Figure 20. Efficiency (Circuit of Figure 19)
Figure 21. Frequency vs VIN (Circuit of Figure 19)
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REVISION HISTORY
Changes from Original (March 2013) to Revision A
•
14
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 13
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PACKAGE OPTION ADDENDUM
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21-Mar-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package Qty
Drawing
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
Top-Side Markings
(3)
(4)
LM34922MY/NOPB
ACTIVE
MSOPPowerPAD
DGQ
10
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-3-260C-168 HR
SA8B
LM34922MYX/NOPB
ACTIVE
MSOPPowerPAD
DGQ
10
3500
Green (RoHS
& no Sb/Br)
CU SN
Level-3-260C-168 HR
SA8B
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
Only one of markings shown within the brackets will appear on the physical device.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 1
Samples
PACKAGE MATERIALS INFORMATION
www.ti.com
26-Mar-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
LM34922MY/NOPB
MSOPPower
PAD
DGQ
10
1000
178.0
12.4
5.3
3.4
1.4
8.0
12.0
Q1
LM34922MYX/NOPB
MSOPPower
PAD
DGQ
10
3500
330.0
12.4
5.3
3.4
1.4
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
26-Mar-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LM34922MY/NOPB
MSOP-PowerPAD
DGQ
10
1000
213.0
191.0
55.0
LM34922MYX/NOPB
MSOP-PowerPAD
DGQ
10
3500
367.0
367.0
35.0
Pack Materials-Page 2
MECHANICAL DATA
DGQ0010A
MUC10A (Rev A)
BOTTOM VIEW
www.ti.com
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