Sample & Buy Product Folder Support & Community Tools & Software Technical Documents LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 LM3670 Miniature Step-Down DC-DC Converter for Ultralow Voltage Circuits 1 Features 3 Description * * * The LM3670 step-down DC-DC converter is optimized for powering ultralow voltage circuits from a single Li-Ion cell or three-cell NiMH/NiCd batteries. It provides up to 350-mA load current, over an input voltage range from 2.5 V to 5.5 V. There are several different fixed voltage output options available as well as an adjustable output voltage version. 1 * * * * * * * * * * * Input Voltage Range: 2.5 V to 5.5 V Adjustable Output Voltages (VOUT): 0.7 V to 2.5 V Fixed Output Voltages: 1.2 V, 1.5 V, 1.6 V, 1.8 V, 1.875 V, 3.3V 15-A Typical Quiescent Current 350-mA Maximum Load Capability 1-MHz PWM Fixed Switching Frequency (Typical) Automatic PFM and PWM Mode Switching Low Dropout Operation - 100% Duty Cycle Mode Internal Synchronous Rectification for High Efficiency Internal Soft Start 0.1-A Typical Shutdown Current Current Overload Protection Operates from a Single Li-Ion Cell or Three-Cell NiMH/NiCd Batteries Only Three Tiny Surface-Mount External Components Required (One Inductor, Two Ceramic Capacitors) 2 Applications * * * * * The device offers superior features and performance for mobile phones and similar portable applications with complex power management systems. Automatic intelligent switching between pulse width modulation (PWM) low-noise and pulse frequency modulation (PFM) low-current mode offers improved system control. During full-power operation, a fixed-frequency 1-MHz (typical) PWM mode drives loads from approximately 70 mA to 350 mA maximum, with up to 95% efficiency. Hysteretic PFM mode extends the battery life through reduction of the quiescent current to 15 A (typical) during light current loads and system standby. Internal synchronous rectification provides high efficiency (90% to 95% typical at loads between 1 mA and 100 mA). In shutdown mode (enable (EN) pin pulled low) the device turns off and reduces battery consumption to 0.1 A (typical). The LM3670 is available in a 5-pin SOT-23 package. A high switching frequency (1 MHz typical) allows use of tiny surface-mount components. Only three external surface-mount components, an inductor and two ceramic capacitors, are required. Mobile Phones and Handheld Devices PDAs Palm-Top PCs Portable Instruments Battery-Powered Devices Device Information(1) PART NUMBER PACKAGE LM3670 SOT-23 (5) BODY SIZE (NOM) 2.90 mm x 1.60 mm (1) For all available packages, see the orderable addendum at the end of the data sheet. space space Typical Application: Fixed Output VIN 2.5 V to 5.5 V CIN 4.7 F L1 10 F VIN 1 5 SW 2 EN 3 4 VOUT COUT 10 F LM3670 GND Typical Application: Adjustable Output Voltage FB VIN 2.5 V to 5.5 V CIN 4.7 F L1 4.7 or 10 H VIN 1 5 SW VOUT LM3670 GND EN 2 3 R1 4 COUT 10 F FB 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. LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com Table of Contents 1 2 3 4 5 6 7 Features .................................................................. Applications ........................................................... Description ............................................................. Revision History..................................................... Connection Diagram.............................................. Specifications......................................................... 1 1 1 2 3 4 6.1 6.2 6.3 6.4 6.5 6.6 4 4 4 4 5 7 Absolute Maximum Ratings ...................................... ESD Ratings.............................................................. Recommended Operating Conditions....................... Thermal Information .................................................. Electrical Characteristics........................................... Typical Characteristics .............................................. Detailed Description ............................................ 10 7.1 Overview ................................................................. 10 7.2 Functional Block Diagram ....................................... 10 7.3 Feature Description................................................. 11 7.4 Device Functional Modes........................................ 12 8 Application and Implementation ........................ 14 8.1 Application Information............................................ 14 8.2 Typical Application ................................................. 14 9 Power Supply Recommendations...................... 18 10 Layout................................................................... 19 10.1 Layout Guidelines ................................................. 19 10.2 Layout Example .................................................... 20 11 Device and Documentation Support ................. 21 11.1 11.2 11.3 11.4 11.5 Device Support .................................................... Community Resources.......................................... Trademarks ........................................................... Electrostatic Discharge Caution ............................ Glossary ................................................................ 21 21 21 21 21 12 Mechanical, Packaging, and Orderable Information ........................................................... 21 4 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision E (February 2013) to Revision F Page * Changed "(0.7V min) to "0.7 V to 2.5 V" ................................................................................................................................ 1 * Added Device Information and Pin Configuration and Functions sections, ESD Ratings and Thermal Information tables, Feature Description, Device Functional Modes, Application and Implementation, Power Supply Recommendations, Layout, Device and Documentation Support, and Mechanical, Packaging, and Orderable Information sections................................................................................................................................................................ 1 * Deleted phone and fax numbers of manufacturers from suggested inductors table ........................................................... 15 * Deleted phone and fax numbers of manufacturers from suggested capacitors table ......................................................... 16 * Deleted rest of text from paragraph beginning "For any output voltages...."........................................................................ 17 * Deleted row beginning with "1.24... "from Table 3 .............................................................................................................. 18 Changes from Revision D (February 2013) to Revision E * 2 Page Changed layout of National Data Sheet to TI format ........................................................................................................... 19 Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 5 Connection Diagram DBV Package 5-Pin SOT-23 Top View SW 5 VIN 1 FB 4 GND 2 EN 3 Pin Functions PIN NUMBE R NAME TYPE DESCRIPTION 1 VIN Power Power supply input. Connect to the input filter capacitor ( Typical Application: Fixed Output). 2 GND Ground Ground pin. 3 EN Digital Enable input. 4 FB Analog Feedback analog input. Connect to the output filter capacitor (Typical Application: Fixed Output). 5 SW Analog Switching node connection to the internal PFET switch and NFET synchronous rectifier. Connect to an inductor with a saturation current rating that exceeds the 750-mA maximum switch peak current limit specification. Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 3 LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com 6 Specifications 6.1 Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted) (1) (2) VIN pin: voltage to GND EN pin: voltage to GND FB, SW pins Junction temperature, TJ-MAX Maximum lead temperature (2) MAX UNIT 6 V V -0.2 6 (GND -0.2) VIN + 0.2 V -45 125 C 260 C 150 C (soldering, 10 seconds) Storage temperature, Tstg (1) MIN -0.2 -45 Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. If Military/Aerospace specified devices are required, contact the TI Sales Office/Distributors for availability and specifications. 6.2 ESD Ratings VALUE V(ESD) (1) (2) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1) 2000 Charged-device model (CDM), per JEDEC specification JESD22C101 (2) 200 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 Recommended Operating Conditions over operating free-air temperature range (unless otherwise noted) (1) MIN Input voltage NOM MAX UNIT 2.5 5.5 A 0 350 mA Junction temperature, TJ -40 125 C Ambient temperature, TA -40 85 C Recommended load current (1) All voltages are with respect to the potential at the GND pin. 6.4 Thermal Information LM3670 THERMAL METRIC (1) DBV (SOT-23) UNIT 5 PINS RJA Junction-to-ambient thermal resistance 163.3 C/W RJC(top) Junction-to-case (top) thermal resistance 114.3 C/W RJB Junction-to-board thermal resistance 26.8 C/W JT Junction-to-top characterization parameter 12.4 C/W JB Junction-to-board characterization parameter 26.3 C/W (1) 4 For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953. Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 6.5 Electrical Characteristics Unless otherwise specified, limits for typical values are TJ = 25C, and minimum and maximum limits apply over the full operating junction temperature range (-40C TJ +125C); VIN = 3.6 V, VOUT = 1.8 V, IOUT = 150 mA, EN = VIN. PARAMETER VIN TEST CONDITIONS See (1) Input voltage Fixed output voltage: 1.2 V Fixed output voltage: 1.5 V Fixed output voltage: 1.6 V, 1.875 V VOUT Fixed output voltage: 1.8 V Fixed output voltage: 3.3 V Adjustable output voltage (2) 2.5 V VIN 5.5 V IOUT = 10 mA MIN -4.5% 2.5 V VIN 5.5 V IOUT = 10 mA -2.5% -2.5% 2.5 V VIN 5.5V 0 mA IOUT 350 mA -5.5% 2.5 V VIN 5.5 V IOUT = 10 mA -1.5% 2.5 V VIN 5.5 V 0 mA IOUT 350 mA -4.5% 3.6 V VIN 5.5 V IOUT = 10 mA -2% 3.6V VIN 5.5V 0 mA IOUT 350 mA -6% 2.5 V VIN 5.5 V IOUT = 10 mA 2.5 V VIN 5.5 V 0 mA IOUT 150 mA UNIT V 4% 4% 4% 4% -5% 2.5 V VIN 5.5 V IOUT = 10 mA MAX 5.5 -2% 2.5 V VIN 5.5 V 0 mA IOUT 150 mA 2.5 V VIN 5.5 V 0 mA IOUT 350 mA TYP 2.5 4% 4% 3% 3% 4% 4% 4.5% -2.5% 4.5% -4% Line_reg Line regulation 2.5 V VIN 5.5 V IOUT = 10 mA Load_reg Load regulation 150 mA IOUT 350 mA VREF Internal reference voltage IQ_SHDN Shutdown supply current TA = 85C 0.1 1 A IQ DC bias current into VIN No load, device is not switching (VOUT forced higher than programmed output voltage) 15 30 A VUVLO Minimum VIN below which VOUT is disabled TA = -40C TJ 125C 2.4 RDSON (P) Pin-pin resistance for PFET VIN = VGS= 3.6V 360 690 m RDSON (N) Pin-pin resistance for NFET VIN = VGS= 3.6 V 250 660 m ILKG (P) P channel leakage current VDS = 5.5 V, TA = 25C 0.1 1 A ILKG (N) N channel leakage current VDS = 5.5 V, TA = 25C 0.1 1.5 A ILIM Switch peak current limit 620 750 mA (1) (2) 0.26 %/V 0.0014 %/mA 0.5 400 V V The input voltage range recommended for the specified output voltages are given below: VIN = 2.5 V to 5.5 V for 0. 7 V VOUT < 1.875 V, VIN = ( VOUT + VDROPOUT) to 5.5 for 1.875 VOUT 3.3 V, where VDROPOUT = ILOAD x (RDSON (P) + RINDUCTOR). Output voltage specification for the adjustable version includes tolerance of the external resistor divider. Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 5 LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com Electrical Characteristics (continued) Unless otherwise specified, limits for typical values are TJ = 25C, and minimum and maximum limits apply over the full operating junction temperature range (-40C TJ +125C); VIN = 3.6 V, VOUT = 1.8 V, IOUT = 150 mA, EN = VIN. PARAMETER Efficiency VIH Logic high input VIL Logic low input IEN Enable (EN) input current OSC Internal oscillator frequency 6 TEST CONDITIONS MIN TYP VIN = 3.6 V, VOUT = 1.8 V ILOAD = 1 mA 91% VIN = 3.6 V, VOUT = 1.8 V ILOAD = 10 mA 94% VIN = 3.6 V, VOUT = 1.8 V ILOAD = 100 mA 94% VIN = 3.6 V, VOUT = 1.8 V ILOAD = 200 mA 94% VIN = 3.6 V, VOUT = 1.8 V ILOAD = 300 mA 92% VIN = 3.6 V, VOUT = 1.8 V ILOAD = 350 mA 90% MAX 1.3 PWM mode Submit Documentation Feedback 550 UNIT V 0.4 V 0.01 1 A 1000 1300 kHz Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 6.6 Typical Characteristics Unless otherwise stated, VIN = 3.6 V and VOUT= 1.8 V. 0.1 TA = 85C ISHUTDOWN (PA) NO LOAD IQUIESCENT (PA) 20 TA = 25C 15 TA = -40C 10 2.5 3 3.5 4 4.5 5 0.05 0 -40 5.5 -20 1.83 1.86 VOUT (V) VOUT (V) IOUT = 150 mA PWM mode PFM Mode 1.82 PWM Mode 1.8 1.78 1.76 VIN = 5.5V VIN = 2.5V 1.74 VIN = 3.6V 1.72 1.7 -20 0 20 40 60 0 80 50 100 150 200 250 300 350 ILOAD (mA) TEMPERATURE (C) Figure 3. VOUT vs VIN Figure 4. VOUT vs IOUT 100 90 80 1.84 1.78 95 60 1.9 1.79 1.77 -40 40 1.88 VIN = 3.6V IOUT = 10 mA PFM mode 1.81 1.80 20 Figure 2. IQ vs Temperature Figure 1. IQ (Non-Switching) vs VIN 1.82 0 TEMPERATURE (C) VIN (V) 100 VIN = 2.7V ILOAD = 150 mA 95 EFFICIENCY (%) EFFICIENCY (%) 85 80 75 VIN = 5.0V 70 65 60 90 ILOAD = 1 mA 85 ILOAD = 300 mA 80 VIN = 3.7V 55 50 75 45 40 -2 10 10 -1 10 0 10 1 10 2 10 3 ILOAD (mA) 70 2.5 3 3.5 4 4.5 5 5.5 6 VIN (V) Figure 5. Efficiency vs IOUT Figure 6. Efficiency vs VIN Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 7 LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com Typical Characteristics (continued) 1010 1000 ILOAD = 150 mA 990 VIN = 3.6V 980 VIN = 5.5V 970 960 950 VIN = 2.5V 940 930 920 910 900 890 880 870 860 850 840 -40 -20 0 10 20 30 40 50 60 70 80 -30 -10 0.8 P FET N FET 0.7 RDSon - N, P CHANNEL (:) FREQUENCY (kHz) Unless otherwise stated, VIN = 3.6 V and VOUT= 1.8 V. TA = 85C TA = 25C TA = -40C 0.6 0.5 0.4 0.3 0.2 0.1 2.5 3 3.5 4 4.5 5 5.5 TEMPERATURE (C) VIN (V) Figure 7. Frequency vs Temperature Figure 8. RDSON vs. VIN P and N Channels IOUT = 100 mA VIN = 3.6V VIN = 4.6V VIN rise time = 10 ms VIN = 3.6V VOUT = 1.8V (20 mV/Div) LINE TRANSIENT LINE TRANSIENT VIN = 2.6V VOUT = 1.8V (20 mV/Div) TIME (200 ms/DIV) VIN = 2.6 V to 3.6 V ILOAD = 100 mA TIME (100 ms/DIV) VIN = 3.6 V to 4.6 V VOUT (50 mV/Div) ILOAD = 280 mA ILOAD = 3 mA Figure 10. Line Transient CURRENT LOAD STEP (0 mA - 70 mA) CURRENT LOAD STEP (3 mA - 280 mA) Figure 9. Line Transient Inductor Current = 200 mA/Div ILOAD = 70 mA ILOAD = 0 mA ILOAD = 0 mA to 70 mA Figure 11. Load Transient 8 VOUT (50 mV/Div) TIME (100 Ps/DIV) TIME (100 Ps/DIV) ILOAD = 3 mA to 280 mA ILOAD = 100 mA Figure 12. Load Transient Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 Typical Characteristics (continued) Unless otherwise stated, VIN = 3.6 V and VOUT= 1.8 V. ILOAD = 150 mA VOUT (20 mV/Div) PWM MODE PFM MODE VSWITCH (5V/Div) Inductor Current (100 mA/Div) VSWITCH (5V/Div) VOUT (20 mV/Div) Inductor Current (200 mA/Div) TIME (1 Ps/DIV) TIME (2 Ps/DIV) CURRENT LOAD STEP (3 mA - 280 mA) Figure 13. PFM Mode VSW, VOUT, IINDUCTOR vs Time Figure 14. PWM Mode VSW, VOUT, IINDUCTOR vs Time VIN (2V/Div) VOUT (1V/Div) Inductor Current (200 mA/ Div) TIME (100 Ps/DIV) ILOAD = 350 mA Figure 15. Soft Start VIN, VOUT, IINDUCTOR vs Time Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 9 LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com 7 Detailed Description 7.1 Overview The LM3670, a high-efficiency step-down DC-DC switching buck converter, delivers a constant voltage from either a single Li-Ion or three-cell NiMH/NiCd battery to portable devices such as cell phones and PDAs. Using a voltage mode architecture with synchronous rectification, the LM3670 can deliver up to 350 mA depending on the input voltage and output voltage (voltage head room), and the inductor chosen (maximum current capability). There are three modes of operation depending on the current required: pulse width modulation (PWM), pulse frequency modulation (PFM), and shutdown. PWM mode handles current loads of approximately 70 mA or higher. Lighter output current loads cause the device to automatically switch into PFM for reduced current consumption (IQ = 15 A typical) and a longer battery life. Shutdown mode turns off the device, offering the lowest current consumption (ISHUTDOWN = 0.1 A typical). The LM3670 can operate up to a 100% duty cycle (PMOS switch always on) for low dropout control of the output voltage. In this way the output voltage is controlled down to the lowest possible input voltage. Additional features include soft-start, undervoltage lockout, current overload protection, and thermal overload protection. As shown in Figure 17, only three external power components are required for implementation. 7.2 Functional Block Diagram VIN EN SW Current Limit Comparator Ramp Generator Soft Start + Undervoltage Lockout Ref1 PFM Current Comparator + Thermal Shutdown 1 MHz Oscillator Bandgap Ref2 PWM Comparator Error Amp + - Control Logic Driver pfm_low 0.5V + - pfm_hi Vcomp 1.0V + - + VREF Zero Crossing Comparator Frequency Compensation Adj Version Fixed Version GND FB 10 Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 7.3 Feature Description 7.3.1 Circuit Operation The LM3670 operates as follows. During the first portion of each switching cycle, the control block in the LM3670 turns on the internal PFET switch. This allows current to flow from the input through the inductor to the output filter capacitor and load. The inductor limits the current to a ramp with a slope of: VIN-VOUT L (1) by storing energy in a magnetic field. During the second portion of each cycle, the controller turns the PFET switch off, blocking current flow from the input, and then turns the NFET synchronous rectifier on. The inductor draws current from ground through the NFET to the output filter capacitor and load, which ramps the inductor current down with a slope of: -VOUT L (2) The output filter stores charge when the inductor current is high, and releases it when low, smoothing the voltage across the load. 7.3.2 Soft Start The LM3670 has a soft-start circuit that limits in-rush current during start-up. Typical start-up times with a 10-F output capacitor and 350-mA load is 400 s: Table 1. Typical Start-Up Times for Soft Start INRUSH CURRENT (mA) DURATION (s) 0 32 70 224 140 256 280 256 620 until soft start ends 7.3.3 LDO - Low Dropout Operation The LM3670 can operate at 100% duty cycle (no switching, PMOS switch is completely on) for low dropout support of the output voltage. In this way the output voltage is controlled down to the lowest possible input voltage. The minimum input voltage needed to support the output voltage is VIN_MIN = ILOAD x (RDSON,PFET + RINDUCTOR) + VOUT where * * * ILOAD = load current RDSON, PFET = the drain to source resistance of PFET switch in the triode region RINDUCTOR = the inductor resistance Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 (3) 11 LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com 7.4 Device Functional Modes 7.4.1 PWM Operation During PWM operation the converter operates as a voltage-mode controller with input voltage feed forward. This allows the converter to achieve excellent load and line regulation. The DC gain of the power stage is proportional to the input voltage. To eliminate this dependence, feed forward inversely proportional to the input voltage is introduced. 7.4.1.1 Internal Synchronous Rectification While in PWM mode, the LM3670 uses an internal NFET as a synchronous rectifier to reduce rectifier forward voltage drop and associated power loss. Synchronous rectification provides a significant improvement in efficiency whenever the output voltage is relatively low compared to the voltage drop across an ordinary rectifier diode. 7.4.1.2 Current Limiting A current limit feature allows the LM3670 to protect itself and external components during overload conditions PWM mode implements cycle-by-cycle current limiting using an internal comparator that trips at 620 mA (typical). 7.4.2 PFM Operation At very light load, the converter enters PFM mode and operates with reduced switching frequency and supply current to maintain high efficiency. The part automatically transition into PFM mode when either of two conditions occurs for a duration of 32 or more clock cycles: 1. The inductor current becomes discontinuous 2. The peak PMOS switch current drops below the IMODE level: VIN (typ) IMODE < 26 mA + 50: (4) During PFM operation, the converter positions the output voltage slightly higher than the nominal output voltage in PWM operation, allowing additional headroom for voltage drop during a load transient from light to heavy load. The PFM comparator senses the output voltage via the feedback pin and control the switching of the output FETs such that the output voltage ramps between 0.8% and 1.6% (typical) above the nominal PWM output voltage. If the output voltage is below the high PFM comparator threshold, the PMOS power switch is turned on. It remains on until the output voltage exceeds the `high' PFM threshold or the peak current exceeds the IPFM level set for PFM mode. The peak current in PFM mode is: VIN (typ) IPFM Peak = 117 mA + 64: (5) Once the PMOS power switch is turned off, the NMOS power switch is turned on until the inductor current ramps to zero. When the NMOS zero-current condition is detected, the NMOS power switch is turned off. If the output voltage is below the high PFM comparator threshold (see Figure 16), the PMOS switch is again turned on and the cycle is repeated until the output reaches the desired level. Once the output reaches the high PFM threshold, the NMOS switch is turned on briefly to ramp the inductor current to zero and then both output switches are turned off and the part enters an extremely low power mode. Quiescent supply current during this sleep mode is less than 30 A, which allows the part to achieve high efficiencies under extremely light load conditions. When the output drops below the low PFM threshold, the cycle repeats to restore the output voltage to approximately 1.6% above the nominal PWM output voltage. If the load current increases during PFM mode (see Figure 16) causing the output voltage to fall below the `low2' PFM threshold, the part automatically transitions into fixed-frequency PWM mode. 12 Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 Device Functional Modes (continued) High PFM Threshold ~1.016 x VOUT PFM Mode at Light Load Load current increases Low1 PFM Threshold ~1.008 x VOUT ZAx is Low PFM Threshold, turn on PFET Low2 PFM Threshold, switch back to PWM mode Current load increases, draws VOUT towards Low2 PFM Threshold Low2 PFM Threshold VOUT is High PFM Voltage Threshold reached, go into sleep mode x Z-A Pfet on until Ipfm limit reached Nfet on drains inductor current until I inductor = 0 PWM Mode at Moderateto-Heavy Loads Figure 16. Operation in PFM Mode and Transition to PWM Mode 7.4.3 Shutdown Setting the EN input pin low (< 0.4 V) places the LM3670 in shutdown mode. During shutdown the PFET switch, NFET switch, reference, control and bias circuitry of the LM3671 are turned off. Setting EN high (> 1.3 V) enables normal operation. It is recommended to set EN pin low to turn off the LM3671 during system power up and undervoltage conditions when the supply is less than 2.5 V. Do not leave the EN pin floating. Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 13 LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com 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 external control of this device is very easy. First make sure the correct voltage been applied at VIN pin, then simply apply the voltage at EN pin according to the Electrical Characteristics to enable or disable the output voltage. 8.2 Typical Application 8.2.1 Typical Application: Fixed Output L1 10 F VIN 2.5 V to 5.5 V VIN CIN 4.7 F 1 5 SW COUT 10 F LM3670 GND 2 EN 3 4 VOUT FB Figure 17. LM3670 Typical Application, Fixed Output 8.2.1.1 Design Requirements For typical CMOS voltage regulator applications, use the parameters listed in Table 2. Table 2. Design Parameters DESIGN PARAMETER EXAMPLE VALUE Minimum input voltage 2.5 V Minimum output voltage 1.2 V Maximum load current 350 mA 8.2.1.2 Detailed Design Procedure 8.2.1.2.1 Inductor Selection There are two main considerations when choosing an inductor: the inductor current must not saturate, and the inductor current ripple is small enough to achieve the desired output voltage ripple. There are two methods to choose the inductor current rating. 8.2.1.2.1.1 Method 1 The total current is the sum of the load and the inductor ripple current. This can be written as IMAX = ILOAD + IRIPPLE (6) 2 VOUT = ILOAD + ( VIN-VOUT 2 *L )( VOUT VIN )( 1 f ) where * * 14 ILOAD = load current VIN = input voltage Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 * * * L = inductor = switching frequency IRIPPLE = peak-to-peak current (7) 8.2.1.2.1.2 Method 2 A more conservative approach is to choose an inductor that can handle the current limit of 700 mA. Given a peak-to-peak current ripple (IPP) the inductor needs to be at least L >= ( VIN - VOUT I PP )*( VOUT VIN 1 )*( ) f (8) A 10-H inductor with a saturation current rating of at least 800 mA is recommended for most applications. Resistance of the inductor resistance must be less than around 0.3 for good efficiency. Table 3 lists suggested inductors and suppliers. For low-cost applications, an unshielded bobbin inductor is suggested. For noise critical applications, a toroidal or shielded-bobbin inductor must be used. A good practice is to lay out the board with overlapping footprints of both types for design flexibility. This allows substitution of a low-noise toroidal inductor, in the event that noise from low-cost bobbin models is unacceptable. 8.2.1.2.2 Input Capacitor Selection A ceramic input capacitor of 4.7 F is sufficient for most applications. A larger value may be used for improved input voltage filtering. The input filter capacitor supplies current to the PFET switch of the LM3670 in the first half of each cycle and reduces voltage ripple imposed on the input power source. The low equivalent series resistance (ESR) of a ceramic capacitor provides the best noise filtering of the input voltage spikes due to this rapidly changing current. Select an input filter capacitor with a surge current rating sufficient for the power-up surge from the input power source. The power-up surge current is approximately the value of the capacitor (F) times the voltage rise rate (V/s). The input current ripple can be calculated by : I RMS = I OUTMAX * VOUT VIN * (1 - The worst case IRMS is: IRMS IRMS = 2 VOUT VIN ) (duty cycle = 50%) (9) Table 3. Suggested Inductors and Their Suppliers MODEL VENDOR IDC2512NB100M Vishay DO1608C-103 Coilcraft ELL6RH100M Panasonic CDRH5D18-100 Sumida 8.2.1.2.3 Output Capacitor Selection The output filter capacitor smooths out current flow from the inductor to the load, maintaining a steady output voltage during transient load changes and reduces output voltage ripple. These capacitors must be selected with sufficient capacitance and sufficiently low ESR to perform these functions. The output ripple current can be calculated as: Voltage peak-to-peak ripple due to capacitance = VPP-C = IPP f*8*C Voltage peak-to-peak ripple due to ESR = VOUT = VPP-ESR = IPP * RESR Voltage peak-to-peak ripple, root mean squared = VPP-RMS = VPP-C2 + VPP-ESR2 Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 15 LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com Note that the output ripple is dependent on the current ripple and the equivalent series resistance of the output capacitor (RESR). Because these two components are out-of-phase the RMS value is used. The RESR is frequency dependent (as well as temperature dependent); make sure the frequency of the RESR given is the same order of magnitude as the switching frequency. Table 4. Suggested Capacitors And Their Suppliers MODEL TYPE VENDOR VJ1812V106MXJAT Ceramic Vishay LMK432BJ106MM Ceramic Taiyo-Yuden JMK325BJ106MM Ceramic Taiyo-Yuden VJ1812V475MXJAT Ceramic Vishay EMK325BJ475MN Ceramic Taiyo-Yuden C3216X5R0J475M Ceramic TDK 10 F for COUT 4.7 F for CIN VOUT (50 mV/Div) ILOAD = 280 mA ILOAD = 0 mA CURRENT LOAD STEP (0 mA - 350 mA) CURRENT LOAD STEP (0 mA - 280 mA) 8.2.1.3 Application Curves TIME (100 Ps/DIV) ILOAD = 0 mA to 280 mA ILOAD = 350 mA ILOAD = 0 mA TIME (100 Ps/DIV) ILOAD = 0 mA to 350 mA Figure 18. Load Transient 16 VOUT (50 mV/Div) Figure 19. Load Transient Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 8.2.2 Typical Application: Adjustable Output VIN 2.5 V to 5.5 V CIN 4.7 F L1 4.7 or 10 H VIN 1 5 SW VOUT LM3670 GND EN 2 3 R1 4 COUT 10 F FB R2 Figure 20. LM3670 Typical Application: Adjustable Output 8.2.2.1 Design Requirements For adjustable LM3670 option, use the design parameters in Table 5 Table 5. Design Parameters DESIGN PARAMETER EXAMPLE VALUE Input voltage range 2.5 V to 5.5 Input capacitor 4.7 F Output capacitor 10 F Inductor 4.7 H or 10 H ADJ programmable output voltage 0.7 V to 2.5 V 8.2.2.2 Detailed Design Procedure 8.2.2.2.1 Output Voltage Selection for Adjustable LM3670 The output voltage of the adjustable parts can be programmed through the resistor network connected from VOUT to VFB then to GND. VOUT is adjusted to make VFB equal to 0.5 V. The resistor from VFB to GND (R2) must be at least 100 K to keep the current sunk through this network well below the 15-A quiescent current level (PFM mode with no switching) but large enough that it is not susceptible to noise. If R2 is 200 K, and VFB is 0.5 V, then the current through the resistor feedback network is 2.5 A (IFB = 0.5 V / R2). The output voltage formula is: R1 VOUT = VFB * ( + 1) R2 where * * * * VOUT = output voltage (V) VFB = feedback voltage (0.5 V typical) R1 Resistor from VOUT to VFB () R2 Resistor from VOUT to GND () (10) For output voltage greater than or equal to 0.7 V a frequency zero must be added at 10 kHz for stability. 1 C1 = 2 *S * R1 *10 kHz (11) For any output voltages equal to 0.7 V or 2.5 V, a pole must also be placed at 10 kHz (see Table 6). Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 17 LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com Table 6. Adjustable LM3670 Configurations for Various VOUT (1) VOUT (V) R1 (K) R2 (K) C1 (pF) C2 (pF) L (H) CIN (F) COUT (F) 0.7 80.6 200 200 150 4.7 4.7 10 0.8 120 200 130 none 4.7 4.7 10 0.9 160 200 100 none 4.7 4.7 10 1.0 200 200 82 none 4.7 4.7 10 1.1 240 200 68 none 4.7 4.7 10 1.2 280 200 56 none 4.7 4.7 10 1.24 221 150 75 120 4.7 4.7 10 1.5 402 200 39 none 10 4.7 10 1.6 442 200 39 none 10 4.7 10 1.7 487 200 33 none 10 4.7 10 1.875 549 200 30 none 10 4.7 14.7 (1) 2.5 806 200 22 82 10 4.7 22 (10 || 4.7) CURRENT LOAD STEP (100 mA - 300 mA) CURRENT LOAD STEP (50 mA - 350 mA) 8.2.2.3 Application Curves VOUT (50 mV/Div) ILOAD = 350 mA ILOAD = 50 mA TIME (100 Ps/DIV) VOUT (50 mV/Div) Inductor Current = 200 mA/Div ILOAD = 300 mA ILOAD = 100 mA TIME (100 ms/DIV) ILOAD = 100 mA to 300 mA ILOAD = 50 mA to 350 mA Figure 22. Load Transient Figure 21. Load Transient 9 Power Supply Recommendations The LM3670 is designed to operate from a stable input supply range of 2.5 V to 5.5 V. 18 Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 10 Layout 10.1 Layout Guidelines PC board layout is an important part of DC-DC converter design. Poor board layout can disrupt the performance of a DC-DC converter and surrounding circuitry by contributing to EMI, ground bounce, and resistive voltage loss in the traces, which can send erroneous signals to the DC-DC converter device, resulting in poor regulation or instability. Good layout for the LM3670 can be implemented by following a few simple design rules, as shown in Figure 23. * Place the LM3670, inductor and filter capacitors close together and make the traces short. The traces between these components carry relatively high switching currents and act as antennas. Following this rule reduces radiated noise. Place the capacitors and inductor within 0.2 in. (5 mm) of the LM3670. * Arrange the components so that the switching current loops curl in the same direction. During the first half of each cycle, current flows from the input filter capacitor, through the LM3670 and inductor to the output filter capacitor and back through ground, forming a current loop. In the second half of each cycle, current is pulled up from ground, through the LM3670 by the inductor, to the output filter capacitor and then back through ground, forming a second current loop. Routing these loops so the current curls in the same direction prevents magnetic field reversal between the two half-cycles and reduces radiated noise. * Connect the ground pins of the LM3670, and filter capacitors together using generous component-side copper fill as a pseudo-ground plane. Then, connect this to the ground-plane (if one is used) with several vias. This reduces ground-plane noise by preventing the switching currents from circulating through the ground plane. It also reduces ground bounce at the LM3670 by giving it a low-impedance ground connection. * Use wide traces between the power components and for power connections to the DC-DC converter circuit. This reduces voltage errors caused by resistive losses across the traces. * Route noise sensitive traces, such as the voltage feedback path, away from noisy traces between the power components. The voltage feedback trace must remain close to the LM3670 circuit, and be direct but must be routed opposite to noisy components. This reduces EMI radiated onto the DC-DC converter's own voltage feedback trace. * Place noise sensitive circuitry, such as radio IF blocks, away from the DC-DC converter, CMOS digital blocks and other noisy circuitry. Interference with noise-sensitive circuitry in the system can be reduced through distance. In mobile phones, for example, a common practice is to place the DC-DC converter on one corner of the board, arrange the CMOS digital circuitry around it (because this also generates noise), and then place sensitive preamplifiers and IF stages on the diagonally opposing corner. Often, the sensitive circuitry is shielded with a metal pan and, by using low-dropout linear regulators, power to the circuit is post-regulated to reduce conducted noise. Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 19 LM3670 SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 www.ti.com 10.2 Layout Example The light shaded area is the top surface ground. COUT, CIN, Feedback R and C grounds all come to this area which is as far away from the SW pin as possible to avoid the noise created at the SW pin. Note that the top and bottom GND sides are kept away from the SW pin to EN,GND,VIN,FB,SW are EN POST PIN the pads for the SOT-23-5 package avoid picking up noise from the SW pin which swings from GND to VIN. EN post pin is connected to EN with a bottom side trace to maintain unbroken ground plane on top of board VIN GND CIN As many through holes as possible here to connect the top and bottom ground planes EN G ND The VIN, SW, VOUT traces, CIN, COUT traces & pads should be thick - they are high current paths Bottom surface - the darker shaded area is all GND EXCEPT for area around SW to avoid picking up switch noise. SW node is switching R2_fb C2_fb COUT S W FB R1_fb between VIN and GND at 1 MHz - VERY NOISY! keep all GNDs and GND planes away! C1_fb VOUT If possible put the feedback Rs and Cs on the back side so the COUT GND can move closer to the IC GND L1 Figure 23. LM3670 Layout 20 Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 LM3670 www.ti.com SNVS250F - NOVEMBER 2004 - REVISED FEBRUARY 2016 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. 11.2 Community Resources The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of Use. TI E2ETM Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help solve problems with fellow engineers. Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and contact information for technical support. 11.3 Trademarks E2E is a trademark of Texas Instruments. All other 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. 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. Submit Documentation Feedback Copyright (c) 2004-2016, Texas Instruments Incorporated Product Folder Links: LM3670 21 PACKAGE OPTION ADDENDUM www.ti.com 23-Aug-2017 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (C) Device Marking (4/5) LM3670MF-1.2/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 SCZB LM3670MF-1.5/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 S82B LM3670MF-1.6/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 SDBB LM3670MF-1.8/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 SDCB LM3670MF-1.875/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 SEFB LM3670MF-3.3 NRND SOT-23 DBV 5 TBD Call TI Call TI -40 to 85 SDEB LM3670MF-3.3/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 SDEB LM3670MF-ADJ/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 SDFB LM3670MFX-1.2/NOPB ACTIVE SOT-23 DBV 5 3000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 SCZB LM3670MFX-1.8/NOPB ACTIVE SOT-23 DBV 5 3000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 SDCB LM3670MFX-ADJ/NOPB ACTIVE SOT-23 DBV 5 3000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 SDFB (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 <=1000ppm threshold. Antimony trioxide based flame retardants must also meet the <=1000ppm threshold requirement. Addendum-Page 1 Samples PACKAGE OPTION ADDENDUM www.ti.com 23-Aug-2017 (3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Device Marking for that device. (6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. 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Addendum-Page 2 PACKAGE MATERIALS INFORMATION www.ti.com 24-Aug-2017 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) LM3670MF-1.2/NOPB SOT-23 DBV 5 1000 178.0 8.4 LM3670MF-1.5/NOPB SOT-23 DBV 5 1000 178.0 LM3670MF-1.6/NOPB SOT-23 DBV 5 1000 178.0 LM3670MF-1.8/NOPB SOT-23 DBV 5 1000 LM3670MF-1.875/NOPB SOT-23 DBV 5 W Pin1 (mm) Quadrant 3.2 3.2 1.4 4.0 8.0 Q3 8.4 3.2 3.2 1.4 4.0 8.0 Q3 8.4 3.2 3.2 1.4 4.0 8.0 Q3 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM3670MF-3.3/NOPB SOT-23 DBV 5 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM3670MF-ADJ/NOPB SOT-23 DBV 5 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM3670MFX-1.2/NOPB SOT-23 DBV 5 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM3670MFX-1.8/NOPB SOT-23 DBV 5 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM3670MFX-ADJ/NOPB SOT-23 DBV 5 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 Pack Materials-Page 1 PACKAGE MATERIALS INFORMATION www.ti.com 24-Aug-2017 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM3670MF-1.2/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0 LM3670MF-1.5/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0 LM3670MF-1.6/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0 LM3670MF-1.8/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0 LM3670MF-1.875/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0 LM3670MF-3.3/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0 LM3670MF-ADJ/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0 LM3670MFX-1.2/NOPB SOT-23 DBV 5 3000 210.0 185.0 35.0 LM3670MFX-1.8/NOPB SOT-23 DBV 5 3000 210.0 185.0 35.0 LM3670MFX-ADJ/NOPB SOT-23 DBV 5 3000 210.0 185.0 35.0 Pack Materials-Page 2 PACKAGE OUTLINE DBV0005A SOT-23 - 1.45 mm max height SCALE 4.000 SMALL OUTLINE TRANSISTOR C 3.0 2.6 1.75 1.45 PIN 1 INDEX AREA 1 0.1 C B A 5 2X 0.95 1.9 1.45 MAX 3.05 2.75 1.9 2 4 0.5 5X 0.3 0.2 3 (1.1) C A B 0.15 TYP 0.00 0.25 GAGE PLANE 8 TYP 0 0.22 TYP 0.08 0.6 TYP 0.3 SEATING PLANE 4214839/C 04/2017 NOTES: 1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing per ASME Y14.5M. 2. This drawing is subject to change without notice. 3. Refernce JEDEC MO-178. www.ti.com EXAMPLE BOARD LAYOUT DBV0005A SOT-23 - 1.45 mm max height SMALL OUTLINE TRANSISTOR PKG 5X (1.1) 1 5 5X (0.6) SYMM (1.9) 2 2X (0.95) 3 4 (R0.05) TYP (2.6) LAND PATTERN EXAMPLE EXPOSED METAL SHOWN SCALE:15X SOLDER MASK OPENING METAL SOLDER MASK OPENING METAL UNDER SOLDER MASK EXPOSED METAL EXPOSED METAL 0.07 MIN ARROUND 0.07 MAX ARROUND NON SOLDER MASK DEFINED (PREFERRED) SOLDER MASK DEFINED SOLDER MASK DETAILS 4214839/C 04/2017 NOTES: (continued) 4. Publication IPC-7351 may have alternate designs. 5. Solder mask tolerances between and around signal pads can vary based on board fabrication site. www.ti.com EXAMPLE STENCIL DESIGN DBV0005A SOT-23 - 1.45 mm max height SMALL OUTLINE TRANSISTOR PKG 5X (1.1) 1 5 5X (0.6) SYMM (1.9) 2 2X(0.95) 4 3 (R0.05) TYP (2.6) SOLDER PASTE EXAMPLE BASED ON 0.125 mm THICK STENCIL SCALE:15X 4214839/C 04/2017 NOTES: (continued) 6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate design recommendations. 7. Board assembly site may have different recommendations for stencil design. www.ti.com PACKAGE OUTLINE DBV0005A SOT-23 - 1.45 mm max height SCALE 4.000 SMALL OUTLINE TRANSISTOR C 3.0 2.6 1.75 1.45 PIN 1 INDEX AREA 1 0.1 C B A 5 2X 0.95 1.9 1.45 MAX 3.05 2.75 1.9 2 4 0.5 5X 0.3 0.2 3 (1.1) C A B 0.15 TYP 0.00 0.25 GAGE PLANE 8 TYP 0 0.22 TYP 0.08 0.6 TYP 0.3 SEATING PLANE 4214839/C 04/2017 NOTES: 1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing per ASME Y14.5M. 2. This drawing is subject to change without notice. 3. Refernce JEDEC MO-178. www.ti.com EXAMPLE BOARD LAYOUT DBV0005A SOT-23 - 1.45 mm max height SMALL OUTLINE TRANSISTOR PKG 5X (1.1) 1 5 5X (0.6) SYMM (1.9) 2 2X (0.95) 3 4 (R0.05) TYP (2.6) LAND PATTERN EXAMPLE EXPOSED METAL SHOWN SCALE:15X SOLDER MASK OPENING METAL SOLDER MASK OPENING METAL UNDER SOLDER MASK EXPOSED METAL EXPOSED METAL 0.07 MIN ARROUND 0.07 MAX ARROUND NON SOLDER MASK DEFINED (PREFERRED) SOLDER MASK DEFINED SOLDER MASK DETAILS 4214839/C 04/2017 NOTES: (continued) 4. Publication IPC-7351 may have alternate designs. 5. Solder mask tolerances between and around signal pads can vary based on board fabrication site. www.ti.com EXAMPLE STENCIL DESIGN DBV0005A SOT-23 - 1.45 mm max height SMALL OUTLINE TRANSISTOR PKG 5X (1.1) 1 5 5X (0.6) SYMM (1.9) 2 2X(0.95) 4 3 (R0.05) TYP (2.6) SOLDER PASTE EXAMPLE BASED ON 0.125 mm THICK STENCIL SCALE:15X 4214839/C 04/2017 NOTES: (continued) 6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate design recommendations. 7. Board assembly site may have different recommendations for stencil design. www.ti.com IMPORTANT NOTICE Texas Instruments Incorporated (TI) reserves the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. 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