LT3751 - High Voltage Capacitor Charger Controller with ...

1 LT3751 . High Voltage Capacitor Charger Controller with Regulation FEATURES DESCRIPTION. nn Charges Any Size Capacitor The LT 3751 is a high input Voltage capable flyback con- nn Low Noise Output in Voltage Regulation Mode troller designed to rapidly charge a large Capacitor to a nn Stable Operation Under a No-Load Condition user-adjustable high target Voltage set by the transformer nn Integrated 2A MOSFET Gate Driver with Rail-to-Rail turns ratio and three external resistors. Optionally, a feed- Operation for VCC 8V back pin can be used to provide a low noise high Voltage nn Selectable or Internal Gate Drive regulated output. Voltage Clamp The LT3751 has an integrated rail-to-rail MOSFET gate nn User-Selectable Over/Undervoltage Detect driver that allows for efficient operation down to nn Easily Adjustable Output Voltage A low 106mV differential current sense threshold volt- nn Primary or Secondary Side Output Voltage Sense age accurately limits the peak switch current .

2 Added pro- nn Wide Input V. CC Voltage Range (5V to 24V) tection is provided via user-selectable overvoltage and nn Available in 20-Pin QFN 4mm 5mm and 20-Lead undervoltage lockouts for both VCC and VTRANS. A typical TSSOP Packages application can charge a 1000 F Capacitor to 500V in less than one second. APPLICATIONS The CHARGE pin is used to initiate a new charge cycle nn High Voltage Regulated Supply and provides ON/OFF control. The DONE pin indicates nn High Voltage Capacitor Charger when the Capacitor has reached its programmed value and nn Professional Photoflash Systems the part has stopped charging. The FAULT pin indicates nn Emergency Strobe when the LT3751 has shut down due to either VCC or nn Security/Inventory Control Systems VTRANS Voltage exceeding the user-programmed supply nn Detonators tolerances.

3 All registered trademarks and trademarks are the property of their respective owners. Protected by Patents including 6518733 and 6636021. TYPICAL APPLICATION. DANGER HIGH Voltage ! OPERATION BY HIGH Voltage TRAINED PERSONNEL ONLY. T1. Load Regulation and Efficiency D1. VTRANS 1:10 500V 500 90. 24V + 330 F 10 F. 0 TO 150mA. 2 2 +. 100 F. 498 84. RVTRANS F. OUTPUT Voltage (V). OFF ON CHARGE RDCM. CLAMP EFFICIENCY (%). RVOUT 496 78. VCC VCC LT3751 . 24V. 10 F HVGATE. TO DONE. MICRO FAULT LVGATE VCC. CSP 494 72. 374k UVLO1 6m . VTRANS 475k OVLO1 CSN 715k 374k 492 66. UVLO2. VCC 475k FB OUTPUT Voltage . OVLO2 EFFICIENCY. GND RBG 10nF 490 60. 0 50 100 150. 732 . LOAD current (mA). 3751 TA01b 3751 TA01a 3751fd For more information 1. LT3751 . ABSOLUTE MAXIMUM RATINGS (Note 1).

4 VCC, CHARGE, current into RVOUT 10mA. DONE, current into RDCM 10mA. LVGATE (Note 8)..24V current into UVLO1 1mA. VCC current into UVLO2 1mA. 9 current into OVLO1 1mA. RBG, CSP, current into OVLO2 1mA. FB ..5V Maximum Junction 125 C. current into DONE 1mA Operating Temperature Range (Note 2).. 40 C to 125 C. current into FAULT 1mA Storage Temperature 65 C to 150 C. current into RV TRANS 1mA. PIN CONFIGURATION. TOP VIEW. TOP VIEW. RVTRANS. UVLO1. RDCM. RVTRANS 1 20 RDCM. NC. UVLO1 2 19 NC 20 19 18 17. OVLO1 3 18 RVOUT OVLO1 1 16 RVOUT. UVLO2 4 17 NC UVLO2 2 15 NC. OVLO2 5 16 RBG OVLO2 3 14 RBG. 21 21. FAULT 6 15 HVGATE FAULT 4 13 HVGATE. DONE 7 14 LVGATE DONE 5 12 LVGATE. CHARGE 8 13 VCC CHARGE 6 11 VCC. CLAMP 9 12 CSP 7 8 9 10. FB 10 11 CSN. CLAMP. FB. CSN. CSP. FE PACKAGE.

5 20-LEAD PLASTIC TSSOP. UFD PACKAGE. TJMAX = 125 C, JA = 38 C/W 20-PIN (4mm 5mm) PLASTIC QFN. EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB TJMAX = 125 C, JA = 43 C/W. EXPOSED PAD (PIN 21) IS GND, MUST BE TIED TO PCB. ORDER INFORMATION #orderinfo LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE. LT3751 EFE#PBF LT3751 EFE#TRPBF LT3751FE 20-Lead Plastic TSSOP 40 C to 125 C. LT3751 IFE#PBF LT3751 IFE#TRPBF LT3751FE 20-Lead Plastic TSSOP 40 C to 125 C. LT3751 EUFD#PBF LT3751 EUFD#TRPBF 3751 20-Pin (4mm 5mm) Plastic QFN 40 C to 125 C. LT3751 IUFD#PBF LT3751 IUFD#TRPBF 3751 20-Pin (4mm 5mm) Plastic QFN 40 C to 125 C. LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE. LT3751 EFE LT3751 EFE#TR LT3751FE 20-Lead Plastic TSSOP 40 C to 125 C.

6 LT3751 IFE LT3751 IFE#TR LT3751FE 20-Lead Plastic TSSOP 40 C to 125 C. LT3751 EUFD LT3751 EUFD#TR 3751 20-Pin (4mm 5mm) Plastic QFN 40 C to 125 C. LT3751 IUFD LT3751 IUFD#TR 3751 20-Pin (4mm 5mm) Plastic QFN 40 C to 125 C. Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: For more information on tape and reel specifications, go to: Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix. 3751fd 2 For more information LT3751 . ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are TA = 25 C.

7 VCC = CHARGE = 5V, CLAMP = 0V, unless otherwise noted. Individual 25k resistors tied from 5V VTRANS supply to RVTRANS, RVOUT, RDCM, unless otherwise noted. (Note 2). PARAMETER CONDITIONS MIN TYP MAX UNITS. VCC Voltage l 24 V. RVTRANS Voltage (Note 3) l 65 V. VCC Quiescent current Not Switching, CHARGE = 5V 8 mA. Not Switching, CHARGE = 0 1 A. RVTRANS, RDCM Quiescent current (Note 4). Not Switching, CHARGE = 5V l 35 40 45 A. Not Switching, CHARGE = 0 1 A. RVOUT Quiescent current (Note 4). Not Switching, CHARGE = 5V l 42 47 52 A. Not Switching, CHARGE = 0 1 A. UVLO1, UVLO2, OVLO1, OVLO2 Clamp Voltage Measured at 1mA into Pin, CHARGE = 0V 55 V. RVTRANS, RVOUT, RDCM Clamp Voltage Measured at 1mA into Pin, CHARGE = 0V 60 V. CHARGE Pin current CHARGE = 24V 425 A. CHARGE = 5V 60 A.

8 CHARGE = 0V 1 A. CHARGE Minimum Enable Voltage l V. CHARGE Maximum Disable Voltage IVCC 1 A l V. Minimum CHARGE Pin Low Time 20 s One-Shot Clock Period l 32 38 44 s VOUT Comparator Trip Voltage Measured at RBG Pin l V. VOUT Comparator Overdrive 2 s Pulse Width, 20 40 mV. RVTRANS, RVOUT = 25k . RBG = . DCM Comparator Trip Voltage Measured as VDRAIN VTRANS, RDCM = 25k , VCC = 350 600 900 mV. (Note 5). current Limit Comparator Trip Voltage FB Pin = 0V l 100 106 112 mV. FB Pin = l 7 11 15 mV. FB Pin Bias current current Sourced from FB Pin, Measured at FB Pin Voltage 64 300 nA. FB Pin Voltage (Note 6) l V. FB Pin Charge Mode Threshold V. FB Pin Charge Mode Hysteresis (Note 7) 55 mV. FB Pin Overvoltage Mode Threshold V. FB Pin Overvoltage Hysteresis 60 mV. DONE Output Signal High 100k to 5V 5 V.

9 DONE Output Signal Low 100k to 5V 40 200 mV. DONE Leakage current DONE = 5V 5 200 nA. FAULT Output Signal High 100k to 5V 5 V. FAULT Output Signal Low 100k to 5V 40 200 mV. FAULT Leakage current FAULT = 5V 5 200 nA. UVLO1 Pin current UVLO1 Pin Voltage = l 50 A. UVLO2 Pin current UVLO2 Pin Voltage = l 50 A. OVLO1 Pin current OVLO1 Pin Voltage = l 50 A. OVLO2 Pin current OVLO2 Pin Voltage = l 50 A. 3751fd For more information 3. LT3751 . ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are TA = 25 C. VCC = CHARGE = 5V, CLAMP = 0V, unless otherwise noted. Individual 25k resistors tied from 5V VTRANS supply to RVTRANS, RVOUT, RDCM, unless otherwise noted. (Note 2). PARAMETER CONDITIONS MIN TYP MAX UNITS.

10 UVLO1 Threshold Measured from Pin to GND l V. UVLO2 Threshold Measured from Pin to GND l V. OVLO1 Threshold Measured from Pin to GND l V. OVLO2 Threshold Measured from Pin to GND l V. Gate Minimum High Time s Gate Peak Pull-Up current VCC = 5V, LVGATE Active A. VCC = 12V, LVGATE Inactive A. Gate Peak Pull-Down current VCC = 5V, LVGATE Active A. VCC = 12V, LVGATE Inactive A. Gate Rise Time 10% 90%, CGATE = (Note 8). VCC = 5V, LVGATE Active 40 ns VCC = 12V, LVGATE Inactive 55 ns Gate Fall Time 90% 10%, CGATE = (Note 8). VCC = 5V, LVGATE Active 30 ns VCC = 12V, LVGATE Inactive 30 ns Gate High Voltage (Note 8): VCC = 5V, LVGATE Active 5 V. VCC = 12V, LVGATE Inactive 10 V. VCC = 12V, LVGATE Inactive, CLAMP Pin = 5V 5 V. VCC = 24V, LVGATE Inactive 10 V. Gate Turn-Off Propagation Delay CGATE = 180 ns 25mV Overdrive Applied to CSP Pin Gate Voltage Overshoot 500 mV.