LMZ12010TZ

LMZ12010 10A, Simple Switcher® Power Module with 20V Maximum Input Voltage April 8, 2011 LMZ12010 10A SIMPLE SWITCHER® Power Module with 20V Maximum Input Voltage Easy to use 11 pin package Performance Benefits ■ High efficiency reduces system heat generation ■ Low radiated emissions (EMI) complies with EN55022 (Note 2) ■ Only 7 external components ■ Low output voltage ripple ■ No external heat sink required System Performance 30117901 TO-PMOD 11 Pin Package 15 x 17.79 x 5.9 mm (0.59 x 0.7 x 0.232 in) θJA = 9.9 °C/W, θJC = 1.0 °C/W (Note 1) RoHS Compliant Efficiency VIN = 12V, VOUT = 3.3V 100 90 EFFICIENCY (%) 80 70 60 50 40 0 1 2345678 OUTPUT CURRENT (A) 12Vin 9 10 Electrical Specifications ■ ■ ■ ■ ■ 50W maximum total output power Up to 10A output current Input voltage range 6V to 20V Output voltage range 0.8V to 6V Efficiency up to 92% 30117902 Key Features ■ ■ ■ ■ ■ ■ ■ ■ ■ Integrated shielded inductor Simple PCB layout Fixed switching frequency (350 kHz) Flexible startup sequencing using external soft-start, tracking and precision enable Protection against inrush currents and faults such as input UVLO and output short circuit – 40°C to 125°C junction temperature range Single exposed pad and standard pinout for easy mounting and manufacturing Fully enabled for Webench® Power Designer Pin compatible with LMZ22010/08/06, LMZ12008/06, LMZ23610/08/06, and LMZ13610/08/06 Thermal derating curve VIN = 12V, VOUT = 3.3V 12 10 8 6 4 2 0 θJA = 9.9 °C/W 20 30 40 50 60 70 80 90 100 110 120 AMBIENT TEMPERATURE (°C) OUTPUT CURRENT (A) 30117908 Radiated EMI (EN 55022) VIN = 12V, VOUT = 5V, IOUT = 10A 50 45 AMPLITUDE (dBμV/m) 40 35 30 25 20 15 10 5 0 Horizontal Peak Vertical Peak Class B Limit Class A Limit 0 100 200 300 400 500 600 700 800 9001000 FREQUENCY (MHz) Applications ■ ■ ■ ■ Point of load conversions from 12V input rail Time critical projects Space constrained / high thermal requirement applications Negative output voltage applications See AN-2027 30117914 Note 1: θJA measured on a 75mm x 90 mm four-layer PCB Note 2: EN 55022:2006, +A1:2007, FCC Part 15 Subpart B, tested on Evaluation Board with EMI configuration © 2011 National Semiconductor Corporation 301179 www.national.com LMZ12010 Simplified Application Schematic 30117920 Connection Diagram 30117932 Top View 11-Lead TO-PMOD Ordering Information Order Number LMZ12010TZ LMZ12010TZE Package Type TO-PMOD-11 TO-PMOD-11 NSC Package Drawing TZA11A TZA11A Supplied As 32 Units in a Rail 250 Units on Tape and Reel Pin Descriptions Pin 1, 2 Name Description VIN Input supply — Nominal operating range is 6V to 20V . A small amount of internal capacitance is contained within the package assembly. Additional external input capacitance is required between this pin and the exposed pad (PGND). Enable — Input to the precision enable comparator. Rising threshold is 1.274V typical. Once the module is enabled, a 13 uA source current is internally activated to facilitate programmable hysteresis. 3, 5, 6 4 AGND Analog Ground — Reference point for all stated voltages. Must be externally connected to PGND(EP). EN www.national.com 2 LMZ12010 Pin 7 Name Description FB Feedback — Internally connected to the regulation amplifier and over-voltage comparator. The regulation reference point is 0.795V at this input pin. Connect the feedback resistor divider between VOUT and AGND to set the output voltage. Soft-Start/Track Input — To extend the 1.6 mSec internal soft-start connect an external soft start capacitor. For tracking connect to an external resistive divider connected to a higher priority supply rail. See applications section. No Connect — This pin must remain floating, do not ground. 8 9 10, 11 EP SS NC VOUT Output Voltage — Output from the internal inductor. Connect the output capacitor between this pin and exposed pad (PGND). PGND Exposed Pad / Power Ground — Electrical path for the power circuits within the module. PGND is not internally connected to AGND (pin 5,6). Must be electrically connected to pins 5 and 6 external to the package. The exposed pad is also used to dissipate heat from the package during operation. Use one hundred 12 mil thermal vias from top to bottom copper for best thermal performance. 3 www.national.com LMZ12010 Absolute Maximum Ratings (Note 3) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN to PGND EN to AGND SS, FB to AGND AGND to PGND Junction Temperature Storage Temperature Range -0.3V to 24V -0.3V to 5.5V -0.3V to 2.5V -0.3V to 0.3V 150°C -65°C to 150°C ESD Susceptibility (Note 4) For soldering specifications: see product folder at www.national.com and www.national.com/ms/MS/MS-SOLDERING.pdf ± 2 kV Operating Ratings (Note 3) 6V to 20V 0V to 5.0V −40°C to 125°C VIN EN Operation Junction Temperature Electrical Characteristics Limits in standard type are for TJ = 25°C only; limits in boldface type apply over the junction temperature (TJ) range of -40°C to +125°C. Minimum and Maximum limits are guaranteed 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, VOUT = 3.3V Symbol Parameter Conditions Min (Note 5) Typ (Note 6) Max (Note 5) Units SYSTEM PARAMETERS Enable Control VEN IEN-HYS Soft-Start ISS tSS Current Limit ICL fosc Current limit threshold Free-running oscillator frequency In-regulation feedback voltage Feedback over-voltage protection threshold Feedback input bias current Non Switching Quiescent Current Shut Down Quiescent Current Maximum Duty Factor Thermal Shutdown Thermal shutdown hysteresis Junction to Ambient (Note 7) Rising Falling Natural Convection 225 LFPM 500 LFPM θJC Δ VO ΔVO/ΔVIN ΔVO/ΔIOUT η η www.national.com EN threshold EN hysteresis source current SS source current Internal soft-start interval VEN rising VEN > 1.274V VSS = 0V 1.096 1.274 13 1.452 V µA 40 50 1.6 60 µA msec A d.c. average 12.5 314 359 404 Internal Switching Oscillator kHz Regulation and Over-Voltage Comparator VFB VFB-OV IFB IQ ISD Dmax TSD TSD-HYST θJA VSS >+ 0.8V IO = 10A 0.775 0.795 0.86 5 3 VEN = 0V 32 85 165 15 9.9 6.8 5.2 1.0 BW@ 20 MHz VIN = 12V to 20V, IOUT= 10A VIN = 12V, IOUT= 0.001A to 10A VIN = 12V VOUT = 3.3V IOUT = 5A VIN = 12V VOUT = 3.3V IOUT = 10A 4 0.815 V V nA mA μA % °C °C °C/W Thermal Characteristics Junction to Case Output voltage ripple Line regulation Load regulation Peak efficiency Full load efficiency °C/W mV PP % mV/A % % PERFORMANCE PARAMETERS(Note 8) 24 ±0.2 1 89.5 87.5 LMZ12010 Note 3: 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 guaranteed specifications and test conditions, see the Electrical Characteristics. Note 4: The human body model is a 100pF capacitor discharged through a 1.5 kΩ resistor into each pin. Test method is per JESD-22-114. Note 5: Min and Max limits are 100% production tested at 25°C. Limits over the operating temperature range are guaranteed through correlation using Statistical Quality Control (SQC) methods. Limits are used to calculate National’s Average Outgoing Quality Level (AOQL). Note 6: Typical numbers are at 25°C and represent the most likely parametric norm. Note 7: Theta JA measured on a 3.0” x 3.5” four layer board, with two ounce copper on outer layers and one ounce copper on inner layers, two hundred and ten 12 mil thermal vias, and 2W power dissipation. Refer to evaluation board application note layout diagrams. Note 8: Refer to BOM in Typical Application Bill of Materials — Table 1. 5 www.national.com LMZ12010 Typical Performance Characteristics Unless otherwise specified, the following conditions apply: VIN = 12V; CIN = three x 10μF + 47nF X7R Ceramic; COUT = two x 330μF Specialty Polymer + 47 uF Ceramic + 47nF Ceramic; CFF = 4.7nF; Tambient = 25° C for waveforms. All indicated temperatures are ambient. Efficiency 5.0V output @ 25°C 100 90 80 70 60 50 40 0 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117934 Dissipation 5.0V output @ 25°C 8 7 DISSIPATION (W) 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117935 EFFICIENCY (%) 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Efficiency 3.3V output @ 25°C 100 90 80 70 60 50 40 0 6Vin 8Vin 10Vin 12Vin 16Vin 20Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117936 Dissipation 3.3V output @ 25°C 8 6Vin 8Vin 10Vin 12Vin 16Vin 20Vin DISSIPATION (W) EFFICIENCY (%) 6 4 2 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117937 www.national.com 6 LMZ12010 Efficiency 2.5V output @ 25°C 100 90 DISSIPATION (W) EFFICIENCY (%) 80 70 60 50 40 30 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117938 Dissipation 2.5V output @ 25°C 8 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117939 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Efficiency 1.8V output @ 25°C 90 80 DISSIPATION (W) EFFICIENCY (%) 70 60 50 40 30 20 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117940 Dissipation 1.8V output @ 25°C 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117941 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Efficiency 1.5V output @ 25°C 90 80 DISSIPATION (W) EFFICIENCY (%) 70 60 50 40 30 20 10 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117942 Dissipation 1.5V output @ 25°C 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117943 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 7 www.national.com LMZ12010 Efficiency 1.2V output @ 25°C 90 80 DISSIPATION (W) EFFICIENCY (%) 70 60 50 40 30 20 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117944 Dissipation 1.2V output @ 25°C 8 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117945 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Efficiency 1.0V output @ 25°C 90 80 DISSIPATION (W) EFFICIENCY (%) 70 60 50 40 30 20 10 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117946 Dissipation 1.0V output @ 25°C 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117947 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Efficiency 5.0V output @ 85°C 100 90 DISSIPATION (W) EFFICIENCY (%) 80 70 60 50 40 30 0 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117948 Dissipation 5.0V output @ 85°C 9 8 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117949 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin www.national.com 8 LMZ12010 Efficiency 3.3V output @ 85°C 100 90 DISSIPATION (W) EFFICIENCY (%) 80 70 60 50 40 30 20 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117950 Dissipation 3.3V output @ 85°C 8 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117951 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Efficiency 2.5V output @ 85°C 100 90 DISSIPATION (W) EFFICIECNY (%) 80 70 60 50 40 30 20 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117952 Dissipation 2.5V output @ 85°C 8 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117953 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Efficiency 1.8V output @ 85°C 90 80 DISSPATION (W) EFFICIENCY (%) 70 60 50 40 30 20 10 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117954 Dissipation 1.8V output @ 85°C 8 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117955 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 9 www.national.com LMZ12010 Efficiency 1.5V output @ 85°C 90 80 DISSPATION (W) EFFICIENCY (%) 70 60 50 40 30 20 10 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117956 Dissipation 1.5V output @ 85°C 8 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117957 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Efficiency 1.2V output @ 85°C 90 80 DISSIPATION (W) EFFICIENCY (%) 70 60 50 40 30 20 10 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117958 Dissipation 1.2V output @ 85°C 8 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117959 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Efficiency 1.0V output @ 85°C 90 80 DISSPATION (W) EFFICIENCY (%) 70 60 50 40 30 20 10 0 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin 2 4 6 8 OUTPUT CURRENT (A) 10 30117960 Dissipation 1.0V output @ 85°C 8 7 6 5 4 3 2 1 0 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117961 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin www.national.com 10 LMZ12010 Normalized line and load regulation VOUT = 3.3V 1.002 NORMALIZED VOUT (V/V) 6 Vin 8 Vin 10 Vin 12 Vin 16 Vin 20 Vin Thermal derating VIN = 12V, VOUT = 5.0V 12 MAXIMUM OUTPUT CURRENT (A) 10 8 6 4 2 0 20 θJA = 9.9 °C/W θJA = 6.8 °C/W θJA = 5.2 °C/W 40 60 80 100 TEMPERATURE (C) 120 30117963 1.001 1.000 0.999 0.998 0 2 4 6 8 OUTPUT CURRENT (A) 10 30117962 Thermal derating VIN = 12V, VOUT = 3.3V 12 MAXIMUM OUTPUT CURRENT (A) 10 8 6 4 2 0 20 θJA = 9.9 °C/W θJA = 6.8 °C/W θJA = 5.2 °C/W 40 60 80 100 TEMPERATURE (C) 120 30117964 θJA vs copper heat sinking area 30 27 24 THETA JA (°C/W) 21 18 15 12 9 6 3 0 2 4 6 8 COPPER AREA (in2) 10 12 30117965 2 Layer 0 LFPM 2 Layer 225 LFPM 4 Layer 0 LFPM 4 Layer 225 LFPM Output ripple 12VIN, 5.0VOUT @ Full Load, BW = 20 MHz Output ripple 12VIN, 5.0VOUT@ Full Load, BW = 250 MHz 30117966 30117969 11 www.national.com LMZ12010 Output ripple 12VIN, 3.3VOUT @ Full Load, BW = 20 MHz Output ripple 12VIN, 3.3VOUT@ Full Load, BW = 250 MHz 30117967 30117970 Output ripple 12VIN, 1.2VOUT @ Full Load, BW = 20 MHz Output ripple 12VIN, 1.2VOUT@ Full Load, BW = 250 MHz 30117968 30117971 Transient response 12VIN, 5.0VOUT 1 to 10A Step Transient response 12VIN, 3.3VOUT 1 to 10A Step 30117972 30117973 www.national.com 12 LMZ12010 Transient response 12VIN, 1.2VOUT 1 to 10A Step Short circuit current vs input voltage 16 14 12 CURRENT (A) 10 8 6 4 2 0 Output Current Input Current 30117974 5 10 15 INPUT VOLTAGE (V) 20 30117975 3.3VOUT Soft Start, no CSS 3.3VOUT Soft Start, CSS = 0.47uF 30117976 301179a4 Block Diagram 30117978 13 www.national.com LMZ12010 General Description The LMZ12010 SIMPLE SWITCHER© power module is an easy-to-use step-down DC-DC solution capable of driving up to 10A load. The LMZ12010 is available in an innovative package that enhances thermal performance and allows for hand or machine soldering. The LMZ12010 can accept an input voltage rail between 6V and 20V and deliver an adjustable and highly accurate output voltage as low as 0.8V. The LMZ12010 only requires two external resistors and external capacitors to complete the power solution. The LMZ12010 is a reliable and robust design with the following protection features: thermal shutdown, programmable input under-voltage lockout, output over-voltage protection, short-circuit protection, output current limit, and allows startup into a pre-biased output. Design Steps for the LMZ12010 Application The LMZ12010 is fully supported by Webench® which offers: component selection, electrical and thermal simulations. Additionally, there are both evaluation and demonstration boards that may be used as a starting point for design. The following list of steps can be used to manually design the LMZ12010 application. All references to values refer to the typical applications schematic Figure 4 . • Select minimum operating VIN with enable divider resistors • Program VOUT with FB resistor divider selection • Select COUT • Select CIN • Determine module power dissipation • Layout PCB for required thermal performance ENABLE DIVIDER, RENT, RENB AND RENHSELECTION Internal to the module is a 2 mega ohm pull-up resistor connected from VIN to Enable. For applications not requiring precision under voltage lock out (UVLO), the Enable input may be left open circuit and the internal resistor will always enable the module. In such case, the internal UVLO occurs typically at 4.3V (VIN rising). In applications with separate supervisory circuits Enable can be directly interfaced to a logic source. In the case of sequencing supplies, the divider is connected to a rail that becomes active earlier in the power-up cycle than the LMZ12010 output rail. Enable provides a precise 1.274V threshold to allow direct logic drive or connection to a voltage divider from a higher enable voltage such as VIN. Additionally there is 13 μA (typ) of switched offset current allowing programmable hysteresis. See Figure 1. The function of the enable divider is to allow the designer to choose an input voltage below which the circuit will be disabled. This implements the feature of a programmable UVLO. The two resistors should be chosen based on the following ratio: RENT / RENB = (VIN UVLO / 1.274V) – 1 (1) The LMZ12010 typical application shows 12.7kΩ for RENB and 42.2kΩ for RENT resulting in a rising UVLO of 5.51V. Note that this divider presents 4.62V to the EN input when VIN is raised to 20V. This upper voltage should always be checked, making sure that it never exceeds the Abs Max 5.5V limit for Enable. A 5.1V Zener clamp can be applied in cases where the upper voltage would exceed the EN input's range of operation. The zener clamp is not required if the target application prohibits the maximum Enable input voltage from being exceeded. Additional enable voltage hysteresis can be added with the inclusion of RENH. It is possible to select values for RENT and RENB such that RENH is a value of zero allowing it to be omitted from the design. Rising threshold can be calculated as follows: VEN(rising) = 1.274 ( 1 + (RENT|| 2 meg)/ RENB) VEN(falling) = VEN(rising) – 13 µA ( RENT|| 2 meg || RENTB + RENH ) (2) Whereas the falling threshold level can be calculated using: (3) 30117979 FIGURE 1. Enable Input Detail www.national.com 14 LMZ12010 OUTPUT VOLTAGE SELECTION Output voltage is determined by a divider of two resistors connected between VOUT and AGND. The midpoint of the divider is connected to the FB input. The regulated output voltage determined by the external divider resistors RFBT and RFBB is: VOUT = 0.795V * (1 + RFBT / RFBB) (4) Rearranging terms; the ratio of the feedback resistors for a desired output voltage is: RFBT / RFBB = (VOUT / 0.795V) - 1 (5) These resistors should generally be chosen from values in the range of 1.0 kΩ to 10.0 kΩ. For VOUT = 0.8V the FB pin can be connected to the output directly and RFBB can be set to 8.06kΩ to provide minimum output load. A table of values for RFBT , and RFBB, is included in the simplified applications schematic on page 2. SOFT-START CAPACITOR SELECTION Programmable soft-start permits the regulator to slowly ramp to its steady state operating point after being enabled, thereby reducing current inrush from the input supply and slowing the output voltage rise-time. Upon turn-on, after all UVLO conditions have been passed, an internal 1.6msec circuit slowly ramps the SS input to implement internal soft start. If 1.6 msec is an adequate turn–on time then the Css capacitor can be left unpopulated. Longer soft-start periods are achieved by adding an external capacitor to this input. Soft start duration is given by the formula: tSS = VREF * CSS / Iss = 0.795V * CSS / 50uA This equation can be rearranged as follows: CSS = tSS * 50μA / 0.795V (7) Using a 0.22μF capacitor results in 3.5 msec typical soft-start duration; and 0.47μF results in 7.5 msec typical. 0.47 μF is a recommended initial value. As the soft-start input exceeds 0.795V the output of the power stage will be in regulation and the 50 μA current is deactivated. Note that the following conditions will reset the soft-start capacitor by discharging the SS input to ground with an internal current sink. • The Enable input being pulled low • A thermal shutdown condition • VIN falling below 4.3V (TYP) and triggering the VCC UVLO TRACKING SUPPLY DIVIDER OPTION The tracking function allows the module to be connected as a slave supply to a primary voltage rail (often the 3.3V system rail) where the slave module output voltage is lower than that of the master. Proper configuration allows the slave rail to power up coincident with the master rail such that the voltage difference between the rails during ramp-up is small (i.e.