View LTM8020_4318377.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

LTM8020 200mA, 36V DC/DC Module FEATURES
n n n n n n n n
DESCRIPTION
The LTM(R)8020 is a complete 200mA, DC/DC step down power supply. Included in the package are the switching controller, power switches, inductor, and all support components. Operating over an input voltage range of 4V to 36V, the LTM8020 supports an output voltage range of 1.25V to 5V, set by a single resistor. Only bulk capacitors are needed to finish the design. The low profile (2.32mm) tiny package enables utilization of unused space on the bottom of PC boards for high density point of load regulation. The LTM8020 is packaged in a thermally enhanced, compact (6.25mm x 6.25mm) and low profile (2.32mm) over-molded Land Grid Array (LGA) package suitable for automated assembly by standard surface mount equipment. The LTM8020 is Pb-free and RoHS compliant.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.
Complete Step-Down Switch Mode Power Supply Wide Input Voltage Range: 4V to 36V 1.25V to 5V Output Voltage 200mA Output Current Current Mode Control -55C to 125C Operating Temperature (LTM8020MPV) Pb-Free (e4) RoHS Compliant Package with Gold Pad Finish Tiny, Low Profile (6.25mm x 6.25mm x 2.32mm) Surface Mount LGA Package
APPLICATIONS
n n n n n
Automotive Battery Regulation Power for Portable Products Distributed Supply Regulation Industrial Supplies Wall Transformer Regulation
TYPICAL APPLICATION
6.5VIN to 36VIN, 5V at 200mA DC/DC Module Regulator
VIN* 6.5V TO 36V 2.2F VIN SHDN GND VOUT LTM8020 BIAS EFFICIENCY (%) ADJ 165k 1% 10F VOUT 5V 200mA
Efficiency and Power Loss vs Load Current
90 80 70 60 50 40 30 20 10 0.1 0.1 1 10 LOAD CURRENT (mA) 100
3470 TA01b
1000
100 POWER LOSS (mW)
10
8020 TA01
1
*RUNNING VOLTAGE RANGE. PLEASE REFER TO APPLICATIONS INFORMATION FOR START-UP DETAILS
8020fb
1
LTM8020 ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
TOP VIEW 5 VOUT 4 GND 3 2 VIN 1 A SHDN B C D E ADJ BIAS
VIN, SHDN Voltage ....................................................40V ADJ Voltage ................................................................5V BIAS Voltage .............................................................25V VIN + BIAS Voltage ....................................................47V VOUT Voltage .............................................................10V Internal Operating Temperature Range... -40C to 125C Storage Temperature Range................... -55C to 125C Maximum Solder Temperature .............................. 260C
LGA PACKAGE 21-LEAD (6.25mm 6.25mm 2.32mm) TJMAX = 125C, JA = 23.1C/W JA DERIVED FROM 5cm x 5cm PCB WITH 4 LAYERS WEIGHT = 0.25g
ORDER INFORMATION
LEAD FREE FINISH LTM8020EV#PBF LTM8020IV#PBF LTM8020MPV#PBF PART MARKING* LTM8020V LTM8020V LTM8020MPV PACKAGE DESCRIPTION 21-Lead (6.25mm x 6.25mm) 21-Lead (6.25mm x 6.25mm) 21-Lead (6.25mm x 6.25mm) TEMPERATURE RANGE (Note 2) -40C to 85C -40C to 85C -55C to 125C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ This product is only offered in trays. For more information go to: http://www.linear.com/packaging/
The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25C. VIN = 10V, VSHDN = 10V, VBIAS = 3V, External CIN = 2.2F COUT = 4.7F , . (Note 2)
SYMBOL VIN VOUT RADJ(MIN) ILK IOUT IQVIN PARAMETER Input DC Voltage Output DC Voltage Minimum Allowable RADJ Leakage from IN to OUT Continuous Output DC Current Quiescent Current into IN 0 < IOUT 200mA; 167k < RADJ < (Note 3) VSHDN = 0V, BIAS = 0V 5.5V VIN 36V, RADJ = 301k, VO = 3.3V SHDN = 0.2V, BIAS OPEN BIAS = 3V, Not Switching BIAS = 0V, Not Switching SHDN = 0.2V, BIAS = 0V BIAS = 3V, Not Switching BIAS = 0V, Not Switching 5V VIN 36V, IOUT = 200mA, RADJ Open VIN = 24V, 0 IOUT 200mA, VOUT = 3.3V
l
ELECTRICAL CHARACTERISTICS
CONDITIONS
l
MIN 4 1.2 163
TYP
MAX 36 5
UNITS V V k A mA A A A A A A % %
1.2 0 10 35 25 1 2
6 200 1 18 50 0.5 60 1.5
IQBIAS
Quiescent Current into BIAS
l
VOUT/VOUT VOUT/VOUT
Line Regulation Load Regulation
8020fb
2
LTM8020 ELECTRICAL CHARACTERISTICS
SYMBOL VOUT(AC_RMS) fSW ISC VADJ VBIAS(MIN) IADJ ISHDN VIH(SHDN) VIL(SHDN) PARAMETER Output Ripple (RMS) Switching Frequency Output Short Circuit Current Voltage at ADJ Pin Minimum BIAS Voltage for Proper Operation Current Out of ADJ Pin SHDN Pin Current SHDN Input High Voltage SHDN Input Low Voltage ADJ = 0V, VOUT = 5V, VSHDN = 0V VSHDN = 2.5V 2.5 0.2
The l denotes the specifications which apply over the full operating , . temperature range, otherwise specifications are at TA = 25C. VIN = 10V, VSHDN = 10V, VBIAS = 3V, External CIN = 2.2F COUT = 4.7F (Note 2)
CONDITIONS IOUT = 100mA, VOUT = 3.3V, VIN = 24V IOUT = 200mA VIN = 36V, VOUT = 0V
l l l
MIN
TYP 7.5 450 350
MAX
UNITS mV kHz mA
1.228 3 9.65 1
1.265
V V
10.35 5
A A V V
Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTM8020E is guaranteed to meet performance specifications from 0C to 85C ambient. Specifications over the full -40C to 85C ambient operating temperature range are assured by design, characterization and correlation with statistical process controls. The
LTM8020I is guaranteed to meet specifications over the full -40C to 85C ambient operating temperature range. The LTM8020MP is guaranteed to meet specifications over the full -55C to 125C internal operating temperature range. Note that the maximum internal temperature is determined by specific operating conditions in conjunction with board layout, the rated package thermal resistance and other environmental factors. Note 3: Guaranteed by design.
TYPICAL PERFORMANCE CHARACTERISTICS
3.3VOUT Efficiency
90 80 70 EFFICIENCY (%) 60 50 40 30 20 10 0 0.1 1 10 ILOAD (mA) 100 5VIN 12VIN 24VIN 36VIN 1000
8020 G01
TA = 25C unless otherwise noted.
3.3VOUT Power Loss
1000 90 80 100 POWER LOSS (mW) EFFICIENCY (%) 5VIN 12VIN 24VIN 36VIN 1 10 IOUT (mA) 100 1000
8020 G02
5VOUT Efficiency
70 60 50 40 30 20 10 0 0.1 1 10 ILOAD (mA) 100 12VIN 24VIN 36VIN 1000
8020 G03
10
1
0.1 0.1
8020fb
3
LTM8020 TYPICAL PERFORMANCE CHARACTERISTICS
5VOUT Power Loss
1000 0.18 0.16 100 POWER LOSS (mW) 0.14 INPUT CURRENT (A) 0.12 0.10 0.08 0.06 0.04 12VIN 24VIN 36VIN 1 10 IOUT (mA) 100 1000
8020 G04
TA = 25C unless otherwise noted. Input Current vs Output Current (12VIN)
0.120 0.100 INPUT CURRENT (A) 0.080 0.060 0.040 0.020 1.8VOUT 2.5VOUT 3.3VOUT 5VOUT
Input Current vs Output Current (5VIN)
1.8VOUT 2.5VOUT 3.3VOUT
10
1
0.02 0 0 0.05 0.10 0.15 OUTPUT CURRENT (A) 0.20
4356 G05
0.1 0.1
0 0 0.05 0.10 0.15 OUTPUT CURRENT (A) 0.20
4356 G06
Input Current vs Output Current (24VIN)
0.060 0.050 INPUT CURRENT (A) 0.040 0.030 0.020 0.010 0.005 0 0 0.05 0.10 0.15 OUTPUT CURRENT (A) 0.20
4356 G07
Input Current vs Output Current (36VIN)
0.045 0.040 0.035 INPUT CURRENT (A) 0.030 0.025 0.020 0.015 0.010 1.8VOUT 2.5VOUT 3.3VOUT 5VOUT 5
Input Quiescent Current vs Input Voltage
QUIESCENT CURRENT (A)
1.8VOUT 2.5VOUT 3.3VOUT 5VOUT
4
3
2
1
0 0 0.05 0.10 0.15 OUTPUT CURRENT (A) 0.20
4356 G08
0 0 10 20 30 INPUT VOLTAGE (V) 40
4356 G09
Input Current vs Input Voltage (Output Short)
100 6.0 5.5 INPUT VOLTAGE (V) 5.0 4.5 4.0 3.5 3.0 0 10 20 30 INPUT VOLTAGE (V) 40
4356 G10
Minimum Required Input Voltage vs Load (VOUT = 3.3V)
TO START 8 7 SHDN CONTROL INPUT VOLTAGE (V) 6 5 4 3 2 0 50 100 150 LOAD CURRENT (mA) 200
4356 G11
Minimum Required Input Voltage vs Output Voltage
IOUT = 200mA TO START
80 INPUT CURRENT (mA)
60
TO RUN
40
TO RUN
20
0
1
2
3 4 OUTPUT VOLTAGE (V)
5
4356 G12
8020fb
4
LTM8020 TYPICAL PERFORMANCE CHARACTERISTICS
Temperature Rise vs Input Voltage (Full Load, TA = 25C)
25 INPUT CURRENT 100mA/DIV VOUT 2V/DIV SHDN 5V/DIV 50s/DIV
8020 G14
TA = 25C unless otherwise noted. Turn-On Behavior (6VIN, 3.3VOUT, No Load)
TEMPERATURE RISE (C)
20
5VOUT
15 3.3VOUT 10
5
0 0 10 20 30 INPUT VOLTAGE (V) 40 50
8020 G13
PIN FUNCTIONS
VIN (Pins A1, A2): The VIN pins supply current to the LTM8020's internal regulator and to the internal power switch. These pins must be locally bypassed with an external, low ESR capacitor of at least 1F . VOUT (Pins A4, A5, B4, B5, C4, C5): Power Output Pins. An external capacitor is connected from VOUT to GND in most applications. Apply output load between these pins and GND. BIAS (Pin C3): The BIAS pin connects to the internal boost Schottky diode and to the internal regulator. Tie to VOUT when VOUT > 3V or to another DC voltage greater than 3V otherwise. When BIAS > 3V the internal circuitry will be powered from this pin to improve efficiency. Main regulator power will still come from VIN. SHDN (Pin C1): The SHDN pin is used to put the LTM8020 in shutdown mode. Tie to ground to shut down the LTM8020. Apply 2V or more for normal operation. If the shutdown feature is not used, tie this pin to VIN. GND (Pins C2, D1, D2, D3, D4, D5, E2, E3, E4, E5): The GND connections serve as the main signal return and the primary heatsink for the LTM8020. Tie the GND pins to a local ground plane below the LTM8020 and the circuit components. Return the feedback divider to this signal. ADJ (Pin E1): The LTM8020 regulates its ADJ pin to 1.25V. Connect the adjust resistor from this pin to GND. The value of this adjust resistor is determined by the equation RADJ = 623.75/(VOUT - 1.25), where RADJ is in k. Note that the ADJ pin is open circuit if VOUT = 1.25V.
8020fb
5
LTM8020 BLOCK DIAGRAM
VIN 0.1F 22H 15pF 499k VOUT 10F
BIAS
SHDN
CURRENT MODE CONTROLLER
GND
ADJ
80220 BD
8020fb
6
LTM8020 OPERATION
The LTM8020 is a stand alone non-isolated step down switching DC/DC power supply. It can deliver up to 200mA of DC output current with only bulk external input and output capacitors. This module provides a precisely regulated output voltage programmable via one external resistor from 1.25VDC to 5VDC. The input voltage range is 4V to 36V. Given that the LTM8020 is a step down converter, make sure that the input voltage is high enough to support the desired output voltage and load current. See Block Diagram. The LTM8020 contains a current mode controller, power switching element, power inductor, power Schottky diode and a modest amount of input and output capacitance. For some applications, as shown in Table 1, no output capacitor is necessary. With its high performance current mode controller and internal feedback loop compensation, the LTM8020 module has sufficient stability margin and good transient performance under a wide range of operating conditions with a wide range of output capacitors, even all ceramic ones (X5R or X7R). Current mode control provides cycle-by-cycle fast
200mA LOAD VOUT 20mV/DIV IL 100mA/DIV IL 100mA/DIV 1s/DIV 150mA LOAD VOUT 20mV/DIV VOUT 20mV/DIV 10mA LOAD 1ms/DIV VOUT 20mV/DIV
current limit, and automatic current limiting protects the module in the event of a short circuit or overload fault. The LTM8020 is built upon a variable frequency controller. The on time, off time and switching frequency are dependent upon the input voltage, output voltage and load current. The drive circuit for the internal power switching element is powered through the BIAS pin. Power this pin with at least 3V. The LTM8020 is equipped with two operating modes, dependant upon the load current. When the load current is sufficiently high, the LTM8020 will switch continuously (see Figure 1a). If the load is very light, or if the input voltage is high relative to the output voltage, the part will operate in Burst Mode(R) operation, alternating between its micropower and switching states to keep the output in regulation and hold the power dissipation to a minimum (See Figure 1b). If the SHDN pin is grounded, all internal circuits are turned off and VIN current reduces to the device leakage current, typically a few nano-amps.
NO LOAD
IL 100mA/DIV 1s/DIV
8020 F1a
IL 100mA/DIV 5s/DIV
8020 F01b
(1a) Continuous Operation
(1b) Burst Mode Operation
Figure 1. Output Voltage and Internal Inductor Current
8020fb
7
LTM8020 APPLICATIONS INFORMATION
For most applications, the design process is straight forward, summarized as follows: 1. Look at Table 1 and find the row that has the desired input range and output voltage. 2. Apply the CIN, COUT, RADJ and BIAS connection indicated on that row. While these component combinations have been tested for proper operation, it is incumbent upon the user to verify proper operation over the intended system's line, load and environmental conditions. If an output voltage other than those listed in Table 1 is desired, use the equation RADJ = 623.75/(VOUT - 1.25), where RADJ is in k. As a starting point, use values for CIN and COUT that correspond to the input voltage and output voltage that most closely matches the intended application, and verify proper operation over the system's line, load and environmental conditions. Capacitor Selection Considerations The CIN and COUT capacitor values in Table 1 are the minimum recommended values for the associated operating conditions. Applying capacitor values below those indicated in Table 1 is not recommended, and may result in undesirable operation. An input system bulk capacitor is assumed. Using larger values is generally acceptable, and can yield improved dynamic response, if it is necessary. Again, it is incumbent upon the user to verify proper operation over the intended system's line, load and environmental conditions. Ceramic capacitors are small, robust and have very low ESR. However, not all ceramic capacitors are suitable. X5R and X7R types are stable over temperature and applied voltage and give dependable service. Other types, including Y5V and Z5U have very large temperature and voltage coefficients of capacitance. In an application circuit they may have only a small fraction of their nominal capacitance resulting in much higher output voltage ripple than expected. Ceramic capacitors are also piezoelectric. The LTM8020's switching frequency depends on the load current, and at light loads it can excite a ceramic capacitor at audio frequencies, generating audible noise. Since the LTM8020 operates at a lower current limit during Burst Mode operation, the noise is typically very quiet to a casual ear. If this audible noise is unacceptable, use a high performance electrolytic capacitor at the output. The input capacitor can be a parallel combination of a 2.2F ceramic capacitor and a low cost electrolytic capacitor. A final precaution regarding ceramic capacitors concerns the maximum input voltage rating of the LTM8020. A ceramic input capacitor combined with trace or cable inductance forms a high Q (under damped) tank circuit. If the LTM8020 circuit is plugged into a live supply, the input voltage can ring to twice its nominal value, possibly exceeding the device's rating. This situation is easily avoided; see the Hot-Plugging Safely section. Shorted Input Protection Care needs to be taken in systems where the output will be held high when the input to the LTM8020 is absent. This may occur in battery charging applications or in battery backup systems where a battery or some other supply is diode OR'ed with the LTM8020's output. If the VIN pin is allowed to float and the SHDN pin is held high (either by a logic signal or because it is tied to VIN), then the LTM8020's internal circuitry will pull its quiescent current through its SW pin. This is fine if your system can tolerate a few milli-amps in this state. If you ground the SHDN pin, the SW pin current will drop to essentially zero. However, if the VIN pin is grounded while the output is held high, then parasitic diodes inside the LTM8020 can pull large currents from the output through the SW pin and the VIN pin. Figure 2 shows a circuit that will run only when the input voltage is present and that protects against a shorted or reversed input.
D1 VIN 100k VIN LTM8020 SHDN GND
8020 F02
1M
Figure 2. Diode D1 Prevents a Shorted Input from Discharging a Backup Battery Tied to the Output, as Well as Protecting the LTM8020 from a Reversed Input
8020fb
8
LTM8020 APPLICATIONS INFORMATION
PCB Layout Most of the headaches associated with PCB layout have been alleviated or even eliminated by the high level of integration of the LTM8020. The LTM8020 is never-theless a switching power supply, and care must be taken to minimize EMI and ensure proper operation. Even with the high level of integration, you may fail to achieve specified operation with a haphazard or poor layout. See Figure 3 for a suggested layout. Ensure that the grounding and heatsinking are acceptable. A few rules to keep in mind are: 1. Place the CIN capacitor as close as possible to the VIN and GND connection of the LTM8020. 2. Place the COUT capacitor as close as possible to the VOUT and GND connection of the LTM8020. 3. Place the CIN and COUT capacitors such that their ground current flows directly adjacent or underneath the LTM8020. 4. Connect all of the GND connections to as large a copper pour or plane area as possible on the top layer. Avoid breaking the ground connection between the external components and the LTM8020. 5. The copper pours also serve as the heatsink for the LTM8020. Place several vias in the GND plane to act as heat pipes to other layers of the printed circuit board.
VIN SHDN VOUT
Positive to Negative Voltage Regulation The LTM8020 can generate a negative output by tying the VOUT pads to system ground and connecting GND as shown in the Typical Applications section. In this configuration, SHDN must be level shifted or referenced to GND, and the available output current may be reduced. Hot-Plugging Safely The small size, robustness and low impedance of ceramic capacitors make them an attractive option for the input bypass capacitor of LTM8020. However, these capacitors can cause problems if the LTM8020 is plugged into a live supply (see Linear Technology Application Note 88 for a complete discussion). The low loss ceramic capacitor combined with stray inductance in series with the power source forms an under damped tank circuit, and the voltage at the VIN pin of the LTM8020 can ring to twice the nominal input voltage, possibly exceeding the LTM8020's rating and damaging the part. If the input supply is poorly controlled or the user will be plugging the LTM8020 into an energized supply, the input network should be designed to prevent this overshoot. Figure 4 shows the waveforms that result when an LTM8020 circuit is connected to a 24V supply through six feet of 24-gauge twisted pair. The first plot is the response with a 2.2F ceramic capacitor at the input. The input voltage rings as high as 35V and the input current peaks at 20A. One method of damping the tank circuit is to add another capacitor with a series resistor to the circuit. In Figure 4b an aluminum electrolytic capacitor has been added. This capacitor's high equivalent series resistance damps the circuit and eliminates the voltage overshoot. The extra capacitor improves low frequency ripple filtering and can slightly improve the efficiency of the circuit, though it is likely to be the largest component in the circuit. An alternative solution is shown in Figure 4c. A 1 resistor is added in series with the input to eliminate the voltage overshoot (it also reduces the peak input current). A 0.1F capacitor improves high frequency filtering. This solution is smaller and less expensive than the electrolytic capacitor. For high input voltages its impact on efficiency is minor, reducing efficiency less than one half percent for a 5V output at full load operating from 24V.
CIN
BIAS
COUT
ADJ COPPER RADJ GND VIAs TO GND PLANE
8020 F03
Figure 3. Layout showing suggested external components, GND plane and thermal vias
8020fb
9
LTM8020 APPLICATIONS INFORMATION
High Temperature Considerations The die temperature of the LTM8020 must be lower than the maximum rating of 125C, so care should be taken in the layout of the circuit to ensure good heat sinking of the LTM8020. To estimate the junction temperature, approximate the power dissipation within the LTM8020 by applying the typical efficiency stated in this datasheet to the desired output power, or, if you have an actual module, by taking a power measurement. Then calculate the internal temperature rise of the LTM8020 above the surface of the printed circuit board by multiplying the module's power dissipation by the thermal resistance. The actual thermal resistance of the LTM8020 to the printed circuit board depends upon the layout of the circuit board, but the thermal resistance given on page 2, which is based upon a 25cm2 4-layer FR4 PC board, and the Typical Performance Characteristics can be used a guide.
CLOSING SWITCH SIMULATES HOT PLUG IIN VIN LTM8020
Finally, be aware that at high ambient temperatures the internal Schottky diode will have significant leakage current increasing the quiescent current of the LTM8020. BIAS Pin Considerations The BIAS pin is used to provide drive power for the internal power switching stage and operate internal circuitry. For proper operation, it must be powered by at least 3V. If the output voltage is programmed to be 3V or higher, simply tie BIAS to VOUT. If VOUT is less than 3V, BIAS can be tied to VIN or some other voltage source. In all cases, ensure that the maximum voltage at the BIAS pin is both less than 25V and the sum of VIN and BIAS is less than 47V. If BIAS power is applied from a remote or noisy voltage source, it may be necessary to apply a decoupling capacitor locally to the LTM8020.
+
2.2F
VIN 10V/DIV
LOW IMPEDANCE ENERGIZED 24V SUPPLY
STRAY INDUCTANCE DUE TO 6 FEET (2 METERS) OF TWISTED PAIR
IIN 10A/DIV 10s/DIV
(4a)
LTM8020
10F 35V AI.EI.
+
2.2F
VIN 10V/DIV
IIN 10A/DIV
(4b)
10s/DIV
1 LTM8020 0.1F 2.2F IIN 10A/DIV VIN 10V/DIV
(4c)
10s/DIV
8020 F04
Figure 4. A Well Chosen Input Network Prevents Input Voltage Overshoot and Ensures Reliable Operation When the LTM8020 is Connected to a Live Supply
8020fb
10
LTM8020 APPLICATIONS INFORMATION
Minimum Input Voltage The LTM8020 is a step-down converter, so a minimum amount of headroom is required to keep the output in regulation. For most applications at full load, the input needs to be at least 1.5V above the desired output. In addition, the input voltage required to turn on depends upon how the SHDN pin is tied. It takes more input voltage
VIN Range 4.5V - 36V 4.5V - 36V 4.5V - 36V 4.5V - 36V 4.5V - 36V 6.5V - 36V 4.5V - 15V 4.5V - 15V 4.5V - 15V 4.5V - 15V 4.5V - 15V 6.5V - 15V 9V - 24V 9V - 24V 9V - 24V 9V - 24V 9V - 24V 9V - 24V 18V - 36V 18V - 36V 18V - 36V 18V - 36V 18V - 36V 18V - 36V 3.3V - 30V 5V - 30V VOUT 1.25V 1.5V 1.8V 2.5V 3.3V 5V 1.25V 1.5V 1.8V 2.5V 3.3V 5V 1.25V 1.5V 1.8V 2.5V 3.3V 5V 1.25V 1.5V 1.8V 2.5V 3.3V 5V -3.3V -5V CIN 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 16V 0805 X7R 2.2F 16V 0805 X7R 2.2F 16V 0805 X7R 2.2F 16V 0805 X7R 2.2F 16V 0805 X7R 2.2F 16V 0805 X7R 1F 25V 0805 X7R 1F 25V 0805 X7R 1F 25V 0805 X7R 1F 25V 0805 X7R 1F 25V 0805 X7R 4.7F 25V 0805 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R 2.2F 50V 1206 X7R
to turn on if SHDN is tied to VIN than if the turn-on is controlled by raising SHDN when VIN is in the required operating range. A graph of the input voltage required to turn the LTM8020 on when SHDN is tied to VIN or when SHDN is switched is given in the Typical Performance Characteristics section.
Table 1. Recommended External Component Values and Configuration
COUT 47F 6.3V 1206 X5R 47F 6.3V 1206 X5R 47F 6.3V 1206 X5R 22F 6.3V 1206 X7R 10F 6.3V 1206 X7R 10F 6.3V 1206 X7R 22F 6.3V 1206 X7R 10F 6.3V 0805 X7R 10F 6.3V 0805 X7R 10F 6.3V 0805 X7R 10F 6.3V 0805 X7R None 47F 6.3V 0805 X5R 47F 6.3V 0805 X7R 10F 6.3V 0805 X7R 10F 6.3V 0805 X7R 10F 6.3V 0805 X7R 10F 6.3V 0805 X5R 47F 6.3V 1206 X5R 47F 6.3V 1206 X5R 22F 6.3V 1206 X7R 10F 6.3V 0805 X7R 10F 6.3V 0805 X7R 10F 6.3V 0805 X7R 22F 6.3V 0805 X7R 10F 6.3V 0805 X7R RADJ Open 2.43M 1.1M 499k 301k 165k Open 2.43M 1.1M 499k 301k 165k Open 2.43M 1.1M 499k 301k 165k Open 2.43M 1.1M 499k 301k 165k 301k 165k BIAS Connection >2V, < 25V >2V, < 25V >2V, < 25V VOUT VOUT VOUT VIN VIN VIN VIN VOUT VOUT VIN VIN VIN VIN VOUT VOUT >2V, <25V >2V, <25V >2V, <25V VOUT VOUT VOUT VOUT VOUT
8020fb
11
LTM8020 TYPICAL APPLICATIONS
1.25V Step-Down Converter
VIN* 4.5V TO 24V 1F VIN SHDN BIAS GND VOUT LTM8020 VOUT 1.25V 200mA
ADJ
47F X5R
8020 TA02
3.3V Step-Down Converter
VIN* 4.5V TO 36V 1F VIN SHDN GND VOUT LTM8020 BIAS ADJ 301k 1% 10F X5R VOUT 3.3V 200mA
8020 TA04
1.8V Step-Down Converter
VIN* 4.5V TO 15V 2.2F VIN SHDN BIAS GND VOUT LTM8020 VOUT 1.8V 200mA
ADJ 1.1M 1%
22F X7R
8020 TA03
*RUNNING VOLTAGE RANGE. PLEASE REFER TO APPLICATIONS INFORMATION FOR START-UP DETAILS
8020fb
12
LTM8020 TYPICAL APPLICATIONS
5V Step-Down Converter (No Output Capacitor Required)
VIN * 6.5V TO 15V 2.2F VIN SHDN GND VOUT LTM8020 BIAS ADJ 165k 1% VOUT 5V 200mA
8020 TA05
-5V Positive to Negative Converter
VIN 5V TO 30V
*
VIN SHDN
VOUT LTM8020 BIAS GND -5V 85mA 10F X5R OPTICAL SCHOTTKY CLAMP
8020 TA06
2.2F ADJ -5V 165k 1%
-5V Positive to Negative Converter Output vs Input Voltage
250
200
ILOAD (mA)
150
100
50
0 0 5 10 15 VIN (V) 20 25 30
8020 TA08
*RUNNING VOLTAGE RANGE. PLEASE REFER TO APPLICATIONS INFORMATION FOR START-UP DETAILS
8020fb
13
LGA Package 21-Lead (6.25mm x 6.25mm x 2.32mm)
(Reference LTC DWG # 05-08-1803 Rev A)
LTM8020
Z
bbb Z
2.5400
1.2700
0.0000
1.2700
2.5400
SUGGESTED PCB LAYOUT TOP VIEW
0.3175 0.0000 0.3175
14
X Y
aaa Z
6.250 BSC 2.22 - 2.42 0.605 - 0.665 5
5.080
0.605 - 0.665
4
PACKAGE DESCRIPTION
3
6.250 BSC MOLD CAP SUBSTRATE 0.27 - 0.37 1.95 - 2.05 1.27O BSC 5.080 BSC
2 C(0.30) PAD 1 1 PADS SEE NOTES E
3
PAD 1 CORNER
aaa Z
DETAIL A
4
PACKAGE TOP VIEW
DETAIL A PACKAGE SIDE VIEW
D
C BOTTOM VIEW
B
A
2.5400
NOTES: 1. DIMENSIONING AND TOLERANCING PER ASME Y14.5M-1994 2. ALL DIMENSIONS ARE IN MILLIMETERS 3 4 DETAILS OF PAD #1 IDENTIFIER ARE OPTIONAL, BUT MUST BE LOCATED WITHIN THE ZONE INDICATED. THE PAD #1 IDENTIFIER MAY BE EITHER A MOLD OR A MARKED FEATURE LAND DESIGNATION PER JESD MO-222, SPP-010 AND SPP-020
1.5875 1.2700 0.9525
0.0000
5. PRIMARY DATUM -Z- IS SEATING PLANE 6. THE TOTAL NUMBER OF PADS: 21 SYMBOL TOLERANCE 0.15 aaa 0.10 bbb
COMPONENT PIN "A1"
LTMXXXXXX mModule
1.2700
2.5400
TRAY PIN 1 BEVEL PACKAGE IN TRAY LOADING ORIENTATION
LGA 21 0407 REV A
8020fb
LTM8020 PACKAGE DESCRIPTION
LTM8020 Pinout (Sorted by Pin Number)
PIN A1 A2 A4 A5 B4 B5 C1 C2 C3 C4 C5 D1 D2 D3 D4 D5 E1 E2 E3 E4 E5 SIGNAL DESCRIPTION VIN VIN VOUT VOUT VOUT VOUT SHDN GND BIAS VOUT VOUT GND GND GND GND GND ADJ GND GND GND GND
8020fb
Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
15
LTM8020 TYPICAL APPLICATION
3.3V Step-Down Converter
VIN* 5V TO 36V 1F VIN SHDN GND VOUT LTM8020 BIAS ADJ 301k 1% 10F X5R VOUT 3.3V 200mA
8020 TA07
*RUNNING VOLTAGE RANGE. PLEASE REFER TO APPLICATIONS INFORMATION FOR START-UP DETAILS
RELATED PARTS
PART NUMBER LTM4600 LTM4600HVMPV LTM4601/ LTM4601A LTM4602 LTM4603 LTM4604 LTM4608 LTM8022 LTM8023 DESCRIPTION 10A DC/DC Module Military Plastic 10A DC/DC Module 12A DC/DC Module with PLL, Output Tracking/Margining and Remote Sensing 6A DC/DC Module 6A DC/DC Module with PLL and Output Tracking/ Margining and Remote Sensing 4A Low VIN DC/DC Module 8A Low VIN DC/DC Module 1A, 36V DC/DC Module 2A, 36V DC/DC Module COMMENTS Basic 10A DC/DC Module, 15mm x 15mm x 2.8mm LGA -55C to 125C Operation, 15mm x 15mm x 2.8mm LGA Synchronizable, PolyPhase Operation, LTM4601-1 Version has no Remote Sensing Pin Compatible with the LTM4600 Synchronizable, PolyPhase Operation, LTM4603-1 Version has no Remote Sensing, Pin Compatible with the LTM4601 2.375V VIN 5V, 0.8V VOUT 5V, 9mm x 15mm x 2.3mm LGA 2.375V VIN 5V, 0.8V VOUT 5V, 9mm x 15mm x 2.8mm LGA Adjustable Frequency, 0.8V VOUT 5V, 11.25mm x 9mm x 2.82mm, Pin Compatible to the LTM8023 Adjustable Frequency, 0.8V VOUT 5V, 11.25mm x 9mm x 2.82mm, Pin Compatible to the LTM8022
8020fb
16 Linear Technology Corporation
(408) 432-1900 FAX: (408) 434-0507
LT 1008 REV B * PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
www.linear.com
(c) LINEAR TECHNOLOGY CORPORATION 2007

▲Up To Search▲

Price & Availability of LTM8020

	To Download LTM8020 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .