LTC3459 10V Micropower Synchronous Boost Converter in ThinSOT U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO The LTC®3459 is a low current, high efficiency synchronous boost converter intended for low power, size constrained portable applications. The LTC3459 can be powered from a single lithium ion battery, a 2- to 3-cell stack of Alkaline or Nickel batteries, or any low impedance voltage source between 1.5V and 5.5V. The output is programmable via an external divider between 2.5V and 10V. Although the part is primarily intended for boost applications, VOUT will maintain regulation below VIN (at reduced efficiency). Small Solution Size >85% Efficiency over Wide Load Range Internal Synchronous Rectifier VIN Range: 1.5V to 5.5V 5V at 30mA from 3.3V Input 3.3V at 20mA from 2 AA Cell Input Programmable Output Voltages Up to 10V Burst Mode® Operation Inrush Current Limiting Output Disconnect in Shutdown Ultralow Quiescent (10µA) and Shutdown (< 1µA) Currents Low Profile (1mm) SOT-23 Package The LTC3459 offers Burst Mode operation with a fixed peak current, providing high conversion efficiency over a wide range of load currents. During start-up, inductor current is controlled preventing the inrush surge current found in many boost converters. In shutdown the output is disconnected from the input and quiescent current is reduced to <1µA. U APPLICATIO S ■ ■ ■ ■ ■ General Purpose Micropower Boost Digital Cameras PDAs LCD Bias Small OLED Displays Supercap Charging The LTC3459 is offered in a low profile (1mm) 6-pin SOT-23 (ThinSOTTM) package allowing a tiny footprint for the total solution. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. ThinSOT is trademark of Linear Technology Corporation. U ■ TYPICAL APPLICATIO Efficiency 5V to 8V Converter 100 22µH VIN = 5V VOUT = 8V 5V VIN VOUT 2M LTC3459 1µF OFF ON VOUT 8V 30mA SHDN GND FB 47pF 4.7µF 365k 3459 TA01a EFFICIENCY (%) 90 SW 80 70 60 50 0.01 0.1 1 ILOAD (mA) 10 100 3459 TA01b 3459f 1 LTC3459 W W W AXI U U ABSOLUTE RATI GS U U W PACKAGE/ORDER I FOR ATIO Referred to GND (Note 1) VIN, FB Voltage ........................................... – 0.3V to 7V VOUT, SHDN Voltage ................................. – 0.3V to 10V SW Voltage ............................................... – 0.3V to 12V Operating Temperature Range (Notes 2, 3) ........................................ – 40°C to 85°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C ORDER PART NUMBER TOP VIEW SW 1 GND 2 FB 3 6 VIN LTC3459ES6 5 VOUT 4 SHDN S6 PACKAGE 6-LEAD PLASTIC TSOT-23 S6 PART MARKING TJMAX = 125°C, θJA = 165°C/W, θJC = 102°C/W LTAHA Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 3.3V, VOUT = 5V, unless otherwise noted. PARAMETER VIN Input Voltage Range VIN Quiescent Current VIN Shutdown Current VOUT Programmable Voltage Range VOUT Quiescent Supply Current VOUT Shutdown Current Reference Feedback Voltage FB Input Leakage Current Converter Performance Peak Switch Current (VIN = 3.3V) tOFF Timer (VIN = 3.3V, VOUT = 5V) Zero Current Comparator Threshold Main NMOS Switch On Resistance Leakage Current Main PMOS Switch On Resistance Leakage Current Logic Inputs SHDN Threshold (Rising Edge) SHDN Hysteresis SHDN Input Leakage Current CONDITIONS MIN ● MAX UNITS 10 0.1 5.5 20 1 V µA µA 2 0.1 10 4 1 V µA µA 1.5 SHDN = VCC SHDN = GND ● TYP 2.5 SHDN = VCC SHDN = GND VIN = 3.3V, VOUT = 7.5V Measured on FB ● 1.19 1.22 10 1.25 50 V nA L = 22µH Varies by 1/(VOUT – VIN) L = 22µH ● 60 225 75 400 0 90 550 mA ns mA VOUT = 5V VSWITCH = 10V, VOUT = 10V 2.8 0.01 VOUT = 5V VIN = 5V, VSWITCH = 5V, VOUT = 0V 4.2 0.02 Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The LTC3459E is guaranteed to meet performance specifications from 0°C to 70°C. Specifications over the – 40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. 0.3 1 Ω µA 2 Ω µA 1 80 0 50 V mV nA Note 3: This IC includes overtemperature protection that is intended to protect the device during momentary overload conditions. Junction temperature will exceed 125°C when overtemperature protection is active. Continuous operation above the specified maximum operating junction temperature may impair device reliability. 3459f 2 LTC3459 U W TYPICAL PERFOR A CE CHARACTERISTICS Minimum ROUT vs VIN 3000 2000 1500 16 VOUT = 10V VOUT = 7.5V VOUT = 5V VOUT = 3.3V L = 22µH 350 300 POUT (mW) 2500 ROUT (Ω) 400 VOUT = 10V VOUT = 7.5V VOUT = 5V VOUT = 3.3V L = 22µH 3500 VIN and VOUT Quiescent Current vs Temperature Minimum POUT vs VIN VIN = 3.3V 14 VOUT = 5V 12 CURRENT (µA) 4000 (TA = 25°C unless otherwise noted.) 250 200 150 IIN 10 8 6 1000 100 4 500 50 2 0 1.5 2 2.5 3.5 3 4 4.5 5 0 1.5 5.5 2 3 2.5 VIN (V) 3.5 4 4.5 1.5 2.0 1.5 1.0 0.5 80 N-Channel and P-Channel MOSFET RDS(ON) vs Temperature 6 4.7µF 10µF 22µF 47µF VOUT = 5V L = 22µH VOUT = 5V 5 PCH 4 RDS(ON) (Ω) 2.0 VOUT = 10V VOUT = 7.5V VOUT = 5V VOUT = 3.3V L = 22µH 60 0 40 20 TEMPERATURE (°C) 3459 G03 VOUT Regulation vs VIN and COUT % CHANGE IN VOUT FREQUENCY (MHz) – 20 3459 G02 Switching Frequency vs VIN at Various VOUTS 2.5 0 –40 5.5 VIN (V) 3459 G01 3.0 5 IOUT 0 –0.5 NCH 3 2 –1.0 1.0 1 –1.5 0.5 1.5 2 2.5 3 3.5 4 4.5 5.5 5 –2.0 1.5 2 2.5 3 3.5 4 4.5 5 5.5 0 –40 –20 VIN (V) VIN (V) 40 20 60 0 TEMPERATURE (°C) 3459 G05 3459 G04 Shutdown Threshold Voltage vs Temperature 80 3459 G06 Burst Cycle Switch Pin Waveform SHUTDOWN THRESHOLD VOLTAGE (V) 1.2 SW CURRENT 50mA/DIV 1.0 SHDN RISING 0.8 SW CURRENT 50mA/DIV SHDN FALLING 0.6 0.4 0.2 0 –40 INDUCTOR CURRENT 50mA/DIV INDUCTOR CURRENT 50mA/DIV VIN = 3.3V VOUT = 5V L = 22µH –20 40 20 60 0 TEMPERATURE (°C) 1µs/DIV 3459 G08 VIN = 3.3V VOUT = 5V L = 22µH 100ns/DIV 3459 G09 80 3459 G07 3459f 3 LTC3459 U W TYPICAL PERFOR A CE CHARACTERISTICS VOUT AC Ripple Burst Cycle VOUT 50mV/DIV INDUCTOR CURRENT 50mA/DIV VIN = 3.3V VOUT = 5V L = 22µH COUT = 4.7µF CFF = 47pF (TA = 25°C unless otherwise noted.) 5µs/DIV Burst Cycle SW CURRENT 50mA/DIV SW CURRENT 50mA/DIV INDUCTOR CURRENT 50mA/DIV INDUCTOR CURRENT 50mA/DIV VIN = 5V VOUT = 10V L = 22µH 3459 G10 VOUT Regulated Below VIN Burst Cycle 1µs/DIV Shorted Output SW CURRENT 50mA/DIV 1µs/DIV 3459 G13 3459 G12 VOUT VOLTAGE 50mA/DIV INDUCTOR CURRENT 50mA/DIV VIN = 5V VOUT = 3.5V L = 22µH 1µs/DIV Start-Up SW CURRENT 50mA/DIV INDUCTOR CURRENT 50mA/DIV VIN = 2V VOUT = 10V L = 22µH 3459 G11 INPUT CURRENT 50mA/DIV VIN = 5V VOUT = 0V L = 22µH 500ns/DIV 3459 G14 Load Steps 250µs/DIV VIN = 3.6V VOUT = 0V TO 8V L = 22µH CIN = 2.2µF 3459 G15 Load Steps VOUT AC RIPPLE 50mV/DIV WITH 50kΩ (TRACE 2 GROUNDED) TO 500Ω (TRACE 2 = 5V) VOUT AC RIPPLE 50mV/DIV WITH 5kΩ (TRACE 2 GROUNDED) TO 500Ω (TRACE 2 = 5V) VIN = 3.6V VOUT = 8V L = 22µH COUT = 4.7µF CFF = 47pF 100µs/DIV 3459 G16 VIN = 3.6V VOUT = 8V L = 22µH COUT = 4.7µF CFF = 47pF 100µs/DIV 3459 G17 3459f 4 LTC3459 U U U PI FU CTIO S SW (Pin 1): Switch Pin. Connect a 15µH to 33µH inductor between SW and VIN. Keep PCB trace lengths as short and wide as possible to reduce EMI and voltage overshoot. If the inductor current falls to zero, the internal P-channel MOSFET synchronous rectifier is turned off to prevent reverse charging of the inductor. GND (Pin 2): Signal and Power Ground. Provide a short, direct PCB path between GND and the (–) side of the filter capacitors on VIN and VOUT. FB (Pin 3): Input to the Burst Mode Comparator. An external resistor divider connected between VOUT, GND and this pin sets the output voltage to: SHDN (Pin 4): Master Shutdown Input. Driving SHDN low disables all IC functions and reduces quiescent current from the battery to less than 2µA. This pin must be pulled above 1V to enable the IC. VOUT (Pin 5): Regulated Output Voltage of the Boost Regulator. Bypass VOUT with a low ESR, ESL ceramic capacitor between 2.2µF and 10µF. VOUT ripple increases with smaller capacitors. VIN (Pin 6): Input Supply Pin. Bypass VIN with a low ESR, ESL ceramic capacitor of at least 1µF. VOUT = 1.22(1 + R1/R2) 3459f 5 LTC3459 W BLOCK DIAGRA 1 SW Q SD IPEAK IZO QB R Q P/~N IZERO DETECT VBEST SW1 S VOUT QB RD VSELECT IZO S 6 + VOUT VSELECT tOFF tOFF TIMER VIN – VCC THERMAL SD 5 SLEEP DELAY P-DRIVE Q R1 RD QB VBEST FB – IPEAK DETECT 3 R2 HYSTCOMP + VCC VCC N-DRIVE N-DRIVE SDB REFOK P-DRIVE SD REFERENCE SD SDB GND SHDN 2 4 3459 BD OFF ON 3459f 6 LTC3459 U OPERATIO Operation boost converter disconnects VOUT from VIN during shutdown to avoid loading the input power source. The LTC3459 synchronous boost converter utilizes a Burst Mode control technique to achieve high efficiency over a wide dynamic range. A 2.5% accurate comparator is used to monitor the output voltage (VOUT), if VOUT is above the comparator threshold no switching occurs and only quiescent current (10µA) is drawn from the power source. When VOUT drops below the comparator threshold, switching commences and the output capacitor is charged. During the on time of the switching period, inductor current is ramped through an internal N-channel MOSFET to GND until a peak current (75mA) is detected. A P-channel MOSFET connects the inductor to VOUT during the off time delivering energy to the load. The off time is controlled by an internal timer which is proportional to 1/(VOUT – VIN). Anticross conduction circuitry ensures the N- and P-channel switches are never on simultaneously. Peak Current Overshoot The LTC3459’s peak current comparator has a delay of approximately 100ns from the time inductor current reaches current limit until the internal N-channel MOSFET turns off. This delay causes the peak current to overshoot based on the inductor value and VIN as follows (Figure 2 is based on a 65mA initial ILIMIT). IPEAK = ILIMIT + (100ns) VIN L tOFF Timer The LTC3459’s tOFF timer is designed to keep the inductor current continuous during a Burst Mode switching packet, thereby increasing current capability at the output. A larger inductor value will have lower peak to peak current ripple, increasing the available current to the load. This improvement is offset somewhat by the reduced IPEAK Only three power components and two feedback resistors are required to complete the design of the boost converter, an external Schottky diode is not required. The high operating frequency allows the use of low value, low profile inductors and tiny external ceramic capacitors. The ~50mVP-P VOUT AC RIPPLE IPEAK tOFF N P tOFF N P BURST ON ~100mA tOFF N P N P N IZERO WAIT SLEEP tOFF P N BURST ON 3459 F01 Figure 1. Inductor Current and VOUT Ripple Waveforms 110 0.8 0.7 100 0.6 15µH 0.5 22µH tOFF (µs) IPEAK (mA) 90 80 33µH 0.4 0.3 70 0.2 60 50 1.5 0.1 2 2.5 3 4 3.5 VIN (V) 4.5 5 5.5 3459 F02 Figure 2. Typical IPEAK Values 0 0.5 1.5 2.5 3.5 4.5 5.5 VOUT – VIN (V) 6.5 7.5 8.5 3459 F03 Figure 3. tOFF Times 3459f 7 LTC3459 U OPERATIO overshoot. The tOFF timer is designed to maintain a relatively constant peak-to-peak current in the inductor despite VIN changes. This is accomplished by varying the tOFF period by approximately 1/(VOUT – VIN). Due to propagation delays and a 0.6µA bias current in the timer, the tOFF time can be more accurately predicted as follows: tOFF ≈ 100ns + 0.8 pF • 1.25V V –V 0.6µA + OUT IN 500k If VOUT is less than VIN, the tOFF delay is fixed at approximately 750ns. U W U U APPLICATIO S I FOR ATIO Inductor Selection An inductor with a minimum value of 15µH is recommended for use with the LTC3459. Values larger than 15µH will result in lower ripple current and switching frequency. High frequency Ferrite core materials are strongly recommended. Some inductors meeting these requirements are listed in Table 2. Table 2. Example Inductors VENDOR/PART Chip Inductors Murata LQH31C LQH32C-Low Profile Taiyo Yuden LB2016 Toko LLB2520 Coilcraft DO3314 DO1606T Sumida CMD4D06 CDRJ2D18LD L DCR (Ω)/ DIMENSIONS (mm) (µH) IMAX (mA) capacitor should also be an X5R type between 2.2µF and 10µF. A larger capacitor should be used if lower peak-topeak output ripple and better line regulation is desired. Table 2. Capacitor Vendor Information SUPPLIER AVX Murata Taiyo Yuden TDK PHONE (803) 448-9411 (714) 852-2001 (408) 573-4150 (847) 803-6100 WEBSITE www.avxcorp.com www.murata.com www.t-yuden.com www.component.tdk.com CONTACT INFORMATION PCB Layout Guidlines www.murata.com 22 22 3/160 0.7/250 3.2 × 1.6 × 1.8 3.2 × 2.5 × 1.6 15 22 33 0.7/130 1/105 1.7/85 2.0 × 1.6 × 1.6 www.t-yuden.com (408) 573-4150 15 22 33 1.7/180 2.5/160 3.8/130 2.5 × 2.0 × 1.6 www.tokoam.com (847) 297-0070 15 0.86/650 3.3 × 3.3 × 1.4 22 1.2/500 15 0.4/700 6.5 × 5.3 × 2.0 22 0.5/500 33 0.74/450 15 0.5/400 6.6 × 5.8 × 0.8 22 0.8/300 33 1.3/240 15 0.175/350 3.2 × 3.2 × 2.0 22 0.255/300 33 0.37/240 The high speed operation of the LTC3459 demands careful attention to board layout. You will not get advertised performance with careless layout. Figure 4 shows the recommended component placement. A large ground pin copper area will help to lower the chip temperature. www.coilcraft.com (847) 639-6400 VIN www.sumida.com (847) 956-0666 Capacitor Selection The boost converter requires two capacitors. The input capacitor should be an X5R type of at least 1.0µF. The VOUT 1 SW VIN 6 2 GND VOUT 5 3 FB SHDN 4 SHDN VOUT 3459 F04 RECOMMENDED COMPONENT PLACEMENT. TRACES CARRYING CURRENT ARE DIRECT. TRACE AREA AT FB PIN IS SMALL. LEAD LENGTH TO BATTERY IS SHORT Figure 4. Recommended Component Placement for Single Layer Board 3459f 8 LTC3459 U TYPICAL APPLICATIO S Very low operating quiescent current and synchronous operation allow for greater than 85% conversion efficiency in many applications. Lower output voltages will result in lower efficiencies since the N- and P-channel RDS(ON)’s will increase. The switching frequency and output power capability of the LTC3459 are also dependant on input and output voltages. 5V from Li-Ion Input 100 VOUT = 5V 15µH* VIN = 4.2V SW VIN 2.5V TO 4.2V Li-Ion BATTERY + 1M LTC3459 1µF SHDN OFF ON VOUT 5V VOUT VIN 47pF 4.7µF FB GND EFFICIENCY (%) 90 VIN = 2.5V 80 70 332k 60 3459 TA04a *COILCRAFT DO3314 50 0.01 0.1 1 ILOAD (mA) 10 100 3459 TA04b 10V from 3.3V or 5V Input 100 VOUT = 10V 33µH* VIN 3.3V TO 5V VIN VOUT 2M LTC3459 1µF OFF ON VOUT 10V SHDN GND 47pF 4.7µF FB EFFICIENCY (%) 90 SW VIN = 5V 80 VIN = 3.3V 70 280k 60 3459 TA05a *COILCRAFT DO3314 50 0.01 0.1 1 ILOAD (mA) 10 100 3459 TA05b 3459f 9 LTC3459 U TYPICAL APPLICATIO S Charging a SuperCap® When VOUT is less than ~3.5V, the body of the internal synchronous P-channel MOSFET rectifier is connected to VIN and the SW pin rises a diode above VIN when current is delivered to the load. While efficiency is compromised in this mode of operation, current to the SuperCap is controlled, preventing any damaging effects of inrush current. Proper heat sinking of the SOT package is required in this application as the die may dissipate 100mW to 200mW during initial charging. When VOUT is greater than ~3.5V normal boost mode operation and efficiency begin, with the P-channel MOSFET acting as a synchronous switch. Average input current is a constant 50mA during charging, where the current delivered to the SuperCap varies somewhat with duty cycle. Once the supercap is charged to 5V, the LTC3459 begins to regulate and the input current is reduced to the amount required to support the load and/or self discharge of the SuperCap. SuperCaps have become a popular alternative to NiCd batteries as backup power sources in portable equipment. Capacitance values of one Farad and higher are achievable in small package sizes with leakage currents in the low microamps. SuperCaps are typically charged at low currents for several minutes until they reach the required back-up voltage. The LTC3459 is designed to control peak inductor current when VIN is greater than or less than VOUT. This allows current to be controlled during start-up in a boost application, for example, or VOUT to be regulated below VIN when powered from a fresh battery. Peak current control makes the LTC3459 an ideal candidate for charging a back-up source such as a SuperCap. Figure 5 shows an application where the LTC3459 is used to charge a two Farad, 5V supercap from a 3.3V input. A NiCd battery could be charged by the LTC3459 as well, but that application may require additional circuitry for proper charge termination. SuperCap is a registered trademark of Baknor Industries. L1 SW VIN 1µF 3.3V + OFF ON VOUT 5V VOUT 1M LTC3459 SHDN GND 1µF COUT 2F FB 332k 3459 F05 COUT: MAXWELL TECHNOLOGIES ULTRACAP PC5-5, 2F, 5V L1: 33µH, 1.7Ω TAIYO YUDEN LB2016 Figure 5. Charging a SuperCap from a 3.3V Source 3459f 10 LTC3459 U PACKAGE DESCRIPTIO S6 Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1636) 0.62 MAX 2.90 BSC (NOTE 4) 0.95 REF 1.22 REF 3.85 MAX 2.62 REF 1.4 MIN 2.80 BSC 1.50 – 1.75 (NOTE 4) PIN ONE ID RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 0.30 – 0.45 6 PLCS (NOTE 3) 0.95 BSC 0.80 – 0.90 0.20 BSC 0.01 – 0.10 1.00 MAX DATUM ‘A’ 0.30 – 0.50 REF 0.09 – 0.20 (NOTE 3) 1.90 BSC S6 TSOT-23 0302 NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING 4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 5. MOLD FLASH SHALL NOT EXCEED 0.254mm 6. JEDEC PACKAGE REFERENCE IS MO-193 3459f 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. 11 LTC3459 U TYPICAL APPLICATIO 3.3V from 2 AA Alkaline Input 100 L1 15µH + C1 2.2µF + OFF ON VIN VOUT LTC3459 FB SHDN GND R1 604k C2 47pF VOUT 3.3V C3 4.7µF R2 365k 3459 TA06a C1: TDK C1608X5R1A225MT C2: TDK C0603COG1E470J C3: TDK C2012X5ROJ475K L1: COILCRAFT DO3314-153MXB R1: PANASONIC ERJ3EKF6043V R2: PANASONIC ERJ3EKF3653V VIN = 3V EFFICIENCY (%) 2 AA CELLS 90 SW VIN 1.8V TO 3V VOUT = 3.3V 80 VIN = 1.8V 70 60 50 0.01 0.1 1 ILOAD (mA) 10 100 3459 TA06b RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1310 1.5A ISW, 4.5MHz, High Efficiency Step-Up DC/DC Converter VIN: 2.75V to 18V, VOUT(MAX) = 35V, IQ = 12mA, ISD < 1µA, MS10E LT1613 550mA ISW, 1.4MHz, High Efficiency Step-Up DC/DC Converter VIN: 0.9V to 10V, VOUT(MAX) = 34V, IQ = 3mA, ISD < 1µA, ThinSOT LT1615/LT1615-1 300mA/80mA ISW, Constant Off-Time, High Efficiency Step-Up DC/DC Converter VIN: 1.2V to 15V, VOUT(MAX) = 34V, IQ = 20µA, ISD < 1µA, ThinSOT LT1618 1.5A ISW, 1.4MHz, High Efficiency Step-Up DC/DC Converter VIN: 1.6V to 18V, VOUT(MAX) = 35V, IQ = 1.8mA, ISD < 1µA, MS10 LT1944 (Dual) Dual Output 350mA ISW, Constant Off-Time, High Efficiency Step-Up DC/DC Converter VIN: 1.2V to 15V, VOUT(MAX) = 34V, IQ = 20µA, ISD < 1µA, MS10 LT1945 (Dual) Dual Output Pos/Neg 350mA ISW, Constant Off-Time, High Efficiency Step-Up DC/DC Converter VIN: 1.2V to 15V, VOUT(MAX) = ±34V, IQ = 20µA, ISD < 1µA, MS10 LT1946/LT1946A 1.5A ISW, 1.2MHz/2.7MHZ, High Efficiency Step-Up DC/DC Converter VIN: 2.45V to 16V, VOUT(MAX) = 34V, IQ = 3.2mA, ISD < 1µA, MS8 LT1949/LT1949-1 550mA ISW, 600kHz/1.1MHz, High Efficiency Step-Up DC/DC Converter VIN: 1.5V to 12V, VOUT(MAX) = 28V, IQ = 4.5mA, ISD < 25µA, SO-8, MS8 LT1961 1.5A ISW, 1.25MHz, High Efficiency Step-Up DC/DC Converter VIN: 3V to 25V, VOUT(MAX) = 35V, IQ = 0.9mA, ISD < 6µA, MS8E LTC3400/LTC3400B 600mA ISW, 1.2MHz, Synchronous Step-Up DC/DC Converter VIN: 0.5V to 5V, VOUT(MAX) = 5V, IQ = 19µA/300µA ISD < 1µA, ThinSOT LTC3401 1A ISW, 3MHz, Synchronous Step-Up DC/DC Converter VIN: 0.5V to 5V, VOUT(MAX) = 6V, IQ = 38µA ISD < 1µA, MS10 LTC3402 2A ISW, 3MHz, Synchronous Step-Up DC/DC Converter VIN: 0.5V to 5V, VOUT(MAX) = 6V, IQ = 38µA ISD < 1µA, MS10 LTC3425 5A ISW, 8MHz, 4-Phase Synchronous Step-Up DC/DC Converter QFN32 VIN: 0.5V to 4.5V, VOUT(MAX) = 5.25V, IQ = 12µA, ISD < 1µA, LTC3429 600mA, 500kHz, Synchronous Step-Up DC/DC Converter with Output Disconnect and Soft-Start VIN: 0.5V to 5V, VOUT(MAX) = 5V, IQ = 20µA/300µA ISD < 1µA, ThinSOT LT3460 320mA ISW, 1.3MHz, High Efficiency Step-Up DC/DC Converter VIN: 2.5V to 16V, VOUT(MAX) = 36V, IQ = 2mA, ISD < 1µA, SC70, ThinSOT LT3464 85mA ISW, Constant Off-Time, High Efficiency Step-Up DC/DC Converter with Integrated Schottky/Output Disconnect VIN: 2.3V to 10V, VOUT(MAX) = 34V, IQ = 25µA, ISD < 1µA, ThinSOT 3459f 12 Linear Technology Corporation LT/TP 0304 1K • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2004