LT4320/LT4320-1 - Ideal Diode Bridge Controller

1 LT4320/LT4320-114320fbFor more information Diode Bridge ControllerThe LT 4320/LT4320-1 are Ideal Diode Bridge controllers that drive four N-channel MOSFETs, supporting voltage rectification from DC to 600Hz typical. By maximizing available voltage and reducing power dissipation (see thermograph comparison below), the Ideal Diode Bridge simplifies power supply design and reduces power supply cost, especially in low voltage applications. An Ideal Diode Bridge also eliminates thermal design problems, costly heat sinks, and greatly reduces PC board area. The LT4320 s internal charge pump supports an all-NMOS design, which eliminates larger and more costly PMOS switches. If the power source fails or is shorted, a fast turn-off minimizes reverse current LT4320 is designed for DC to 60Hz typical voltage rectification, while the LT4320-1 is designed for DC to 600Hz typical voltage rectification.

2 Higher frequencies of operation are possible depending on MOSFET size and operating load Maximizes Power Efficiencyn Eliminates Thermal Design Problemsn DC to 600Hz n 9V to 72V Operating Voltage Rangen IQ = (Typical)n Maximizes Available Voltagen Available in 8-Lead (3mm 3mm) DFN, 12-Lead MSOP and 8-Lead PDIP Packages n Security Camerasn Terrestrial or Airborne Power Distribution Systemsn Power-over-Ethernet Powered Device with a Secondary Inputn Polarity-Agnostic Power Inputn Diode Bridge ReplacementL, LT, LT C, LT M, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Patent pending.+ ~~TG1IN1LT4320BG2IN2BG1TG2 OUTNOUTP4320 TA01aOUTPUT9V TO 72 VINPUTDC TO 600Hz (TYP)Thermograph of Passive Diode BridgeThermograph of LT4320 Driving Four MOSFETsSBM1040 ( 4)4320 TA01btypical application Temperature RiseCURRENT MOSFET Diode SBM C15 C32 C49 C8A11 C66 C10A16 C84 CDC Input, On Same PCBLT4320+ FET ( 4)CONDITIONS: 24V ACIN, DC LOAD ON SAME PCB4320 TA01cLT4320/LT4320-124320fbFor more information conFigurationabsolute MaxiMuM ratingsSupply Voltages IN1, IN2.

3 3V to 80V OUTP .. to 80 VOutput Voltages (Note 3) BG1, BG2, TG1, TG2 .. to 80V TG1-IN1, TG2-IN2 .. to 12V(Notes 1, 2)TOP VIEW9DD PACKAGE8-LEAD (3mm 3mm) PLASTIC DFN56784321IN2TG2BG2BG1IN1TG1 OUTPOUTN TJMAX = 150 C, JC = C/W EXPOSED PAD (PIN 9) MUST BE CONNECTED TO OUTN (PIN 5)123456IN2TG2 NCNCBG2BG1121110987IN1TG1 NCOUTPNCOUTNTOP VIEW13 MSE PACKAGE12-LEAD PLASTIC MSOP TJMAX = 150 C, JC = 10 C/W EXPOSED PAD (PIN 13) MUST BE CONNECTED TO OUTN (PIN 7)12348765 TOP VIEWIN2TG2BG2BG1IN1TG1 OUTPOUTNN8 PACKAGE8-LEAD PLASTIC DIP TJMAX = 150 C, JC = 45 C/WorDer inForMationLEAD FREE FINISHTAPE AND REELPART MARKING*PACKAGE DESCRIPTIONOPERATING JUNCTION TEMPERATURE RANGELT4320 IDD#PBFLT4320 IDD#TRPBFLGCV8-Lead (3mm 3mm) Plastic DFN 40 C to 85 CLT4320 HDD#PBFLT4320 HDD#TRPBFLGCV8-Lead (3mm 3mm) Plastic DFN 40 C to 125 CLT4320 IDD-1#PBFLT4320 IDD-1#TRPBFLGCW8-Lead (3mm 3mm) Plastic DFN 40 C to 85 CLT4320 HDD-1#PBFLT4320 HDD-1#TRPBFLGCW8-Lead (3mm 3mm)

4 Plastic DFN 40 C to 125 CLT4320 IMSE#PBFLT4320 IMSE#TRPBF432012-Lead Plastic MSOP 40 C to 85 CLT4320 HMSE#PBFLT4320 HMSE#TRPBF432012-Lead Plastic MSOP 40 C to 125 CLT4320 MPMSE#PBFLT4320 MPMSE#TRPBF432012-Lead Plastic MSOP 55 C to 125 CLT4320 IMSE-1#PBFLT4320 IMSE-1#TRPBF4320112-Lead Plastic MSOP 40 C to 85 CLT4320 HMSE-1#PBFLT4320 HMSE-1#TRPBF4320112-Lead Plastic MSOP 40 C to 125 CLT4320 MPMSE-1#PBFLT4320 MPMSE-1#TRPBF4320112-Lead Plastic MSOP 55 C to 125 CLT4320IN8#PBFNALT4320N88-Lead PDIP 40 C to 85 CLT4320HN8#PBFNALT4320N88-Lead PDIP 40 C to 125 CLT4320IN8-1#PBFNALT4320N8-18-Lead PDIP 40 C to 85 CLT4320HN8-1#PBFNALT4320N8-18-Lead PDIP 40 C to 125 CConsult LT C Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LT C Marketing for information on nonstandard lead based finish more information on lead free part marking, go to: For more information on tape and reel specifications, go to: Junction Temper atur e Range LT4320I.

5 40 C to 85 C LT4320H .. 40 C to 125 C LT4320MP .. 55 C to 125 CStorage Temper atur e Range .. 65 C to 150 CLead Temper atur e (Soldering, 10 sec) MSE, PDIP Packages ..300 CLT4320/LT4320-134320fbFor more information characteristics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C. (Note 2)SYMBOLPARAMETERCONDITIONSMINTYPMAXUNIT SOUTP Voltage Rangel972 VOUTP Undervoltage Lockout (UVLO) ThresholdINn = OUTP, Other IN = Turn-On/Off Threshold OUTP = 9V, Other IN = Pin Current INn = OUTP+ VSD(MAX) + 5mV, Other IN = 0Vl Pin Current at 9V at 72 VINn = OUTP+ VSD(MAX) + 5mV, Other IN = 0V l l 44 63 A mA VSDT opside Source-Drain Regulation Voltage (INn OUTP) LT4320 LT4320-1 l l 8 26 20 40 35 55 mV mV VTGATETop Gate Drive (TGn INn)INn = OUTP+ VSD(MAX) + 5mV, 10 A Out of TGn, Other IN = Gate Drive (BGn)

6 INn = OUTP, 10 A Out of BGn, Other IN = Gate Pull-Up CurrentTGn INn = 0V, INn = OUTP + TGn INn = 5V, INn = OUTP + Current Flows Out of TGn, Other IN = 0Vl l425 120 A AITGSnTop Gate Pull-Down Current to INn TGn INn = 5V, INn = OUTP Current Flows Into TGn, Other IN = Gate Pull-Down Current to OUTN INn = 0V, Other IN = OUTP = , TGn = 5V Current Flows Into TGn Gate Pull-Up CurrentBGn = 5V; INn = OUTP = , Other IN = 0V Current Flows Out of Gate Pull-Down Current BGn = 5V; INn = 0V, Other IN = OUTP = Current Flows Into 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Unless otherwise specified, exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and 2: All voltages are referenced to OUTN = 0V unless otherwise 3: Externally forced voltage absolute maximums.

7 The LT4320 may exceed these limits during normal operation. LT4320/LT4320-144320fbFor more information perForMance characteristicsVBGATE vs OUTPTGn Pull-Up StrengthTGn Pull-Down Strength to INnTGn Pull-Down Strength to OUTNBGn Pull-Up StrengthBGn Pull-Down StrengthIINn and IOUTP vs OUTPIOUTP vs OUTP VTGATE vs OUTPINn = OUTP (V)00 CURRENT ( A)20040060080010001200204060804320 G01 OUTPINnOTHER IN = 0 VOUTP (V)00 IOUTP ( A)20040060080010001200204060804320 G02IN1 AND IN2 FLOATINGOUTP (V)9 VTGATE (V)89254320 G03761317211110 VSD = 100mV VSD = 40mVOTHER IN = 0 VOUTP (V)96 VBGATE (V)789101112131721254320 G04 OTHER IN = 0V VTGATE (V)00 ITGn ( A)20040060024684320 G0510800100010030050070090012 OUTP = 9 VOUTP = 12 VOUTP = 72 VINn = OUTP + 100mVOTHER IN = 0V VTGATE (V)00 ITGSn (mA)1234524684320 G061012 OUTP = 9 VOUTP = 72 VINn = OUTP 250mVOTHER IN = 0 VTGn (V)00 ITGGn (mA)102030406024684320 G07101250 INn = 0 VOTHER IN = OUTPOUTP = 9 VOUTP = 12 VOUTP = 72 VVBGATE (V)00 IBGUn (mA)254810124320 G081432614 OTHER IN = 0 VVINn = 9 VVINn = 12 VVINn = 72 VVBGATE (V)0353025201510506104320 G0924812 IBGDn (mA)LT4320/LT4320-154320fbFor more information Functions(DFN, PDIP/MSOP)IN2 (Pin 1/Pin 1): Bridge Rectifier Input.

8 IN2 connects to the external NMOS transistors MTG2 source, MBG1 drain and the power input. TG2 (Pin 2/Pin 2): Topside Gate Driver Output. TG2 pin drives MTG2 (Pin 3/Pin 5): Bottom-Side Gate Driver Output. BG2 pin drives MBG2 (Pin 4/Pin 6): Bottom-Side Gate Driver Output. BG1 pin drives MBG1 (Pin 5/Pin 7): OUTN is the rectified negative output voltage, and connects to the sources of MBG1 and MBG2. OUTP (Pin 6/Pin 9): OUTP is the rectified positive output voltage that powers the LT4320 and connects to the drains of MTG1 and (Pin 7/Pin 11): Topside Gate Driver Output. TG1 pin drives MTG1 gate. IN1 (Pin 8/Pin 12): Bridge Rectifier Input. IN1 connects to the external NMOS transistors MTG1 source, MBG2 drain, and the power input. NC (Pins 3, 4, 8, 10, MSOP Only): No Connections. Not internally Pad (Pin 9/Pin 13): Exposed Pad, DFN and MSOP. Must be connected to BDMTG1 OUTNBG1IN1LT4320IN2 MBG1BG2 MTG2 MBG2TG1+ ~~TG2 CONTROL block DiagraMLT4320/LT4320-164320fbFor more information systems that receive power from an AC power source or a DC polarity-agnostic power source often em-ploy a 4- Diode rectifier.

9 The traditional Diode Bridge comes with an efficiency loss due to the voltage drop generated across two conducting diodes. The voltage drop reduces the available supply voltage and dissipates significant power especially in low voltage applications. By maximizing available voltage and reducing power dis-sipation, the Ideal Diode Bridge simplifies power supply design and reduces power supply cost. An Ideal Diode Bridge also eliminates thermal design problems, costly heat sinks, and greatly reduces PC board area. The LT4320 is designed for DC to 60Hz typical voltage rectification, while the LT4320-1 is designed for DC to 600Hz typical voltage rectification. Higher frequencies of operation are possible depending on MOSFET size and operating load 2 presents sample waveforms illustrating the gate pins in an AC voltage rectification design. TG2IN1 CLOADTO LOADINPUTLT4320IN2+ ~~OUTPOUTNBG2TG1 MTG1 MTG2 MBG2 MBG1BG14320 F0140V30V20V10V0V4320 F02 VTG1 VTG2 VBG1 VBG2 VIN1 VOUTPVIN2 Figure 1.

10 LT4320 with Four N-Channel MOSFETS, Illustrating Current Flow When IN1 Is PositiveFigure 2. 24V AC Sample WaveformLT4320/LT4320-174320fbFor more information inForMationMOSFET SelectionA good starting point is to reduce the voltage drop of the Ideal Bridge to 30mV per MOSFET with the LT4320 (50mV per MOSFET with the LT4320-1). Given the average output load current, IAVG, select RDS(ON) to be: RDS(ON)=30 mVIAVGfor a D C power i nputorRDS(ON)=30 mV3 IAVGfor a n AC power i nputIn the AC power input calculation, 3 IAVG assumes the duration of current conduction occupies 1/3 of the AC the maximum allowable drain-source voltage, VDSS, to be higher than the maximum input ExampleFor a 24W, 12V DC/24V AC application, IAVG = 2A for 12V DC. To cover the 12V DC case: RDS(ON)=30 mV2A=15 m For the 24V AC operation, IAVG = 1A. To cover the 24V AC case: RDS(ON)=30 mV3 1A=10 m This provides a starting range of RDS(ON) values to choose the MOSFET can handle a continuous current of 3 IAVG to cover the expected peak currents during AC rec-tification.