LT3751EUFD#PBF Linear Technology, LT3751EUFD#PBF Datasheet
LT3751EUFD#PBF
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LT3751EUFD#PBF Summary of contents
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... LT3751 has shut down due to either V exceeding the user-programmed supply tolerances. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6518733 and 6636021. ...
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... T = 38°C/W JMAX JA EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT3751EFE#PBF LT3751EFE#TRPBF LT3751IFE#PBF LT3751IFE#TRPBF LT3751EUFD#PBF LT3751EUFD#TRPBF LT3751IUFD#PBF LT3751IUFD#TRPBF LEAD BASED FINISH TAPE AND REEL LT3751EFE LT3751EFE#TR LT3751IFE LT3751IFE#TR LT3751EUFD LT3751EUFD#TR LT3751IUFD LT3751IUFD#TR Consult LTC Marketing for parts specifi ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are T resistors tied from 5V V supply to RV TRANS PARAMETER V Voltage CC RV Voltage TRANS V Quiescent Current Quiescent Current TRANS DCM RV Quiescent Current OUT ...
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LT3751 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are T resistors tied from 5V V supply to RV TRANS PARAMETER UVLO1 Threshold UVLO2 Threshold OVLO1 Threshold OVLO2 Threshold Gate Minimum High Time Gate Peak Pull-Up Current Gate Peak Pull-Down Current ...
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TYPICAL PERFORMANCE CHARACTERISTICS V Pin Current –40°C 1 25°C 125° PIN VOLTAGE (V) 3751 G01 CHARGE Pin Minimum Enable Voltage 1.3 1.2 1.1 1.0 0.9 0.8 ...
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LT3751 TYPICAL PERFORMANCE CHARACTERISTICS Current Comparator Trip Voltage (Charge Mode) 109 – CSP CSN 108.5 108.0 107 12V 24V CC 107.0 –40 – ...
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TYPICAL PERFORMANCE CHARACTERISTICS HVGATE Pin Clamp Voltage 11 24V CC CLAMP = 0V 10.9 10.8 10.7 10.6 10.5 10.4 –40 – 100 120 TEMPERATURE (°C) 3751 G19 PIN FUNCTIONS (TSSOP/QFN) RV (Pin 1/Pin ...
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LT3751 PIN FUNCTIONS DONE (Pin 7/ Pin 5): Open Collector Indication Pin. When the target output voltage (charge mode) is reached or the FAULT pin goes low, a transistor turns on. This pin needs a proper pull-up resistor or current ...
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BLOCK DIAGRAM CHARGE OFF ON OTLO MASTER CC 12V LATCH 100k DONE 10μ 100k FAULT FAULT LATCH + 3.8V – UVLO1 UVLO1 191k – V TRANS ...
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... When the NMOS switch latch is set, and depending on the use of LVGATE, the gate driver rapidly charges the gate pin to V – high voltage applications or directly low voltage applications (refer to the Application CC Burst Mode is a registered trademark of Linear Technology Corporation LPRI V – V TRANS DS(ON) ...
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OPERATION Information section for proper use of LVGATE). With the gate driver output high, the external NMOS turns on, forcing V – V across the primary winding. TRANS DS(ON) Consequently, current in the primary coil rises linearly at a rate ...
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LT3751 OPERATION At very low output voltages, the boundary-mode switching cycle period increases signifi cantly such that the energy stored in the transformer core is not depleted before the next clock cycle. In this situation, the clock may initiate another ...
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OPERATION CHARGE MODE 26kHz ONE-SHOT CLK SWITCH MAXIMUM NO BLANKING ENABLE PEAK CURRENT I PRI HEAVY LOAD OPERATION 26kHz ONE-SHOT CLK SWITCH PEAK CURRENT ENABLE CONTROL FORCED BLANKING I PRI t ≈ 38μs PER DUTY CYCLE ( ...
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LT3751 OPERATION Periodic Refresh When the LT3751 enters regulation, the internal circuitry deactivates switching when the internal one-shot clock is high. The clock operates at a 1/20th duty cycle with a minimum blank time of 1.5μs. This reset pulse is ...
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APPLICATIONS INFORMATION The LT3751 charger controller can be optimized for either capacitor charging only or low noise regulation applica- tions. Several equations are provided to aid in the design process. Safety Warning Large capacitors charged to high voltage can deliver ...
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LT3751 APPLICATIONS INFORMATION The total propagation delay the second most dominant d factor that affects effi ciency and is the summation of gate driver on-off propagation delays and the discharge time associated with the secondary winding capacitance. ...
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APPLICATIONS INFORMATION Table 1. Recommended Transformers MANUFACTURER PART NUMBER Coilcraft DA2033-AL www.coilcraft.com DA2034-AL GA3459-BL GA3460-BL HA4060-AL HA3994-AL Würth Elektronik/Midcom 750032051 www.we-online.com 750032052 750310349 750310355 Sumida C8117 www.sumida.com C8119 PS07-299 PS07-300 TDK DCT15EFD-U44S003 www.tdk.com DCT20EFD-U32S003 DCT25EFD-U27S005 *Transformer has three secondaries where ...
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LT3751 APPLICATIONS INFORMATION with V between 100V and 400V (refer to Typical TRANS Applications section). Consult applications engineering for applications with V operating above 400V. TRANS RV is required for capacitor charger applications but OUT may be removed for regulator ...
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APPLICATIONS INFORMATION Table 4. Recommended Output Diodes MANUFACTURER PART NUMBER Central Semiconductor CMR1U-10M www.centralsemi.com CMSH2-60M CMSH5-40 Fairchild Semiconductor ES3J www.fairchildsemi.com ES1G ES1J On Semiconductor MURS360 www.onsemi.com MURA260 MURA160 Vishay USB260 www.vishay.com US1G US1M GURB5H60 Gate Driver Operation The LT3751 gate ...
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LT3751 APPLICATIONS INFORMATION detected to when the gate transitions to the low state. This delay increases the peak current limit by (V )(180ns)/L . TRANS PRI Sense resistor inductance (L RSENSE current limit error. L creates an input offset voltage ...
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APPLICATIONS INFORMATION Two problems can arise from large V magnitude of the spike may require an NMOS with an unnecessarily high V which equates to a larger (BR)DSS R . Secondly, the V node will ring—possibly DS(ON) DRAIN below ground—causing ...
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LT3751 APPLICATIONS INFORMATION Large Signal Stability Large signal stability can be an issue when audible noise is a concern. Figure 12 shows that the problem originates from the one-shot clock and the output voltage ripple. The load must be constrained ...
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APPLICATIONS INFORMATION SECONDARY PRIMARY LT3751 3751fb 23 ...
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LT3751 APPLICATIONS INFORMATION 24 SECONDARY PRIMARY 3751fb ...
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TYPICAL APPLICATIONS DANGER HIGH VOLTAGE! OPERATION BY HIGH VOLTAGE TRAINED PERSONNEL ONLY V TRANS + 12V TO 24V C3 1000μF RV TRANS CHARGE OFF ON CLAMP LT3751 CC 12V TO 24V C1 R10, 100k 10μF DONE R11, ...
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LT3751 TYPICAL APPLICATIONS DANGER HIGH VOLTAGE! OPERATION BY HIGH VOLTAGE TRAINED PERSONNEL ONLY V TRANS + 5V TO 24V C3 R6 680μF 40.2k RV TRANS OFF ON CHARGE RDCM CLAMP LT3751 24V C1 ...
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TYPICAL APPLICATIONS DANGER HIGH VOLTAGE! OPERATION BY HIGH VOLTAGE TRAINED PERSONNEL ONLY V F1, 1A TRANS 100V TO + 400VDC R6 C3 625k 47μF R7, 96.2k RV TRANS OFF ON CHARGE RDCM CLAMP LT3751 10V TO ...
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LT3751 TYPICAL APPLICATIONS DANGER HIGH VOLTAGE! OPERATION BY HIGH VOLTAGE TRAINED PERSONNEL ONLY V F1, 1A TRANS 100V TO + 400VDC C3 R6, 625k 47μF R7, 97.6k RV TRANS OFF ON CHARGE RDCM CLAMP V LT3751 10V ...
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... R7 THRU R12, R15 THRU R20: 0805 RESISTORS, 1% D1: 12V ZENER D2: VISHAY MURS140 D3: VISHAY P6KE200A D4: VISHAY MURS160 D5: STMICROELECTRONICS STTH112A D6: VISHAY BAT54 T1: TDK SRW24LQ D7: NXP SEMICONDUCTORS BAS516 (Np:Ns:Npb:Nsb = 1:2:0.08:0.08) M1: VISHAY IRF830 U1: NEC PS2801-1 M2: STMICROELECTRONICS STB11NM60FD U2: LINEAR TECHNOLOGY LT4430 Load Regulation 0.50 0.25 0 –0.25 –0. 100 150 200 I ...
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LT3751 TYPICAL APPLICATIONS Wide Input Voltage Range, 15 Watt, Triple Output Voltage Regulator 24V C1, C3: 25V X5R OR X7R CERAMIC C2: 25V SANYO 25ME1000AX C4, C5: 35V SANYO 35ME470AX C6: 10V KEMET T520D107M010ASE055 C7, C8: ...
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PACKAGE DESCRIPTION 6.60 ±0.10 4.50 ±0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 0.50 – 0.75 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE IN ...
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LT3751 PACKAGE DESCRIPTION 2.65 ± 0.05 4.50 ± 0.05 1.50 REF 3.10 ± 0.05 0.25 ±0.05 0.50 BSC RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 5.00 ...
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... Revised Applications Information section Revised Typical Applications illustration 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LT3751 ...
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... Photofl ash LT3585-2/LT3585-3 Capacitor Charger with Adjustable Input Current and IGBT Drivers LT3750 Capacitor Charger Controller ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 34 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...