SI9122 Vishay Siliconix, SI9122 Datasheet
SI9122
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SI9122 Summary of contents
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... D Voltage Feedforward Compensation D High Voltage Pre-Regulator Operates During Start-Up D Current Sensing On Low-Side Primary Device DESCRIPTION Si9122 is a dedicated half-bridge IC ideally suited to fixed telecom applications where efficiency is required at low output voltages (e.g. <3.3 V). Designed to operate within the fixed telecom voltage range of 33−72 V and withstand 100 V, ...
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... Si9122 provides intelligent gate drive signals to control the secondary MOSFETs. With independent gate drive signals from the controller, transformer design is no longer limited by the gate to a source rating of the MOSFETs. Si9122 provides constant V voltage, independent of line voltage to minimize the gate GS charge loss as well as conduction loss ...
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... OSC NOM OSC f = 500 kHz, V − 150 mV NOM CS2 CS1 100Hz V − GND, V − GND CS1 CS2 Si9122 Vishay Siliconix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65 to 150_C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 mA Limits −40 to 85_C Min Typ Max 3.2 3.3 3.4 −50 − ...
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... Si9122 Vishay Siliconix a SPECIFICATIONS Parameter Symbol Current Sense Amplifier Input amplifier Offset Voltage V OS CL_CONT Current CL_CONT Current I I CL_CONT CL_CONT Lower Current Limit Threshold V TLCL Upper Current Limit Threshold V THCL Hysteresis CL_CONT Clamp Level C L_CONT(min) PWM Operation D MAX e Duty Cycle ...
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... 0.3 nF SRH SRH SRL SRL Input to high-side switch off Input to low-side switch off Input to high-side switch off Input to low-side switch off Si9122 Vishay Siliconix Limits −40 to 85_C Min Typ Max Unit − 0 0.3 LX 1.3 1.9 2.7 −1.1 − ...
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... Si9122 Vishay Siliconix TIMING DIAGRAM FOR MOS DRIVERS V CC PWM GND GND GND V BST V MID D H GND V CC GND t BBM1 BBM1 www.vishay.com 6 PWM PWM BBM2 BBM3 BBM4 ...
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... PIN CONFIGURATION Si9122DQ (TSSOP-20 REG_COMP REF GND OSC INDET CS1 9 CS2 10 Top View Standard Part Number Si9122DQ-T1 PIN DESCRIPTION Pin Number Name 1 V Input supply voltage for the start-up circuit REG_COMP Control signal for an external pass transistor. ...
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... High Voltage Protection Interface OTP Synchronous V CC Synchronous Si9122 capacitor, bootstrap capacitor and the soft-start CC capacitor should therefore be CC can be supplied from the external circuit (e.g via CC is then maintained above V CC REG , an internal voltage clamp turns Document Number: 71815 S-41944— ...
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... To prevent oscillations, a longer soft-start time may be needed for high capacitive loads and high peak output current applications. Reference The reference voltage of Si9122 is set at 3.3 V. The reference voltage is de-coupled externally with 0.1-mF capacitor. The V voltage shutdown mode and has 50-mA source REF capability ...
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... CC H −0.3 V. Thus, the CC divider must be set to accommodate IN operating voltage to avoid this condition GND may INDET or V supplies INEXT R EXT V IN PNP Ext (Si9122) Auxillary HV DMOS REG_COMP C VCC C EXT 0 14.5 V GND High-Voltage Pre-Regulator Circuit OSC OFFSET ...
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... REF CC −50 − Temperature (_C) SRL, SRH Duty Cycle vs. V 100 90 3 INDET 0.0 0.5 1.0 1 vs. Temperature 8.20 8. +1.25 mV/C 8.10 V INDET 8.05 8.00 7.95 7.90 −50 − 100 Temperature (_C) Si9122 75 100 EP 2 REF 125 150 www.vishay.com 11 ...
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... Si9122 Vishay Siliconix TYPICAL CHARACTERISTICS I vs. Temperature REG2 −50 − Temperature (_C SOURCE 250 200 CC 150 100 200 400 V (mV) OH SRL, SRH I SOURCE 200 400 V (mV) OH www.vishay.com ...
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... BBM3 1. BBM4 BBM BBM4 t BBM4 BBM3 BBM3 BBM3 20 −50 − Temperature (_C) www.vishay.com Si9122 t BBM4 t BBM1 t BBM2 t BBM3 BBM1 BBM1 = 12 V 100 125 = 100 125 13 ...
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... Si9122 Vishay Siliconix TYPICAL CHARACTERISTICS t vs. V vs. V BBM1 BBM1 BBM2 BBM2 30 3.5 4.5 5.5 V (V) INDER t vs. V vs. V BBM3 BBM4 BBM4 BBM3 BBM3 30 3.5 4.5 5.5 V (V) ...
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... OUT V 2 V/div OUT DH 5 V/div SRL 5 V/div D 5 V/div L SRH 5 V/div For related documents such as package/tape drawings, part marking, and reliability data, see Si9122 Vishay Siliconix Normal Mode 0.1 W Figure ms/div 200 ms/div Figure 12. Drive Waveforms 500 ns/div www.vishay.com ...
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− R27 FZT953 GND FMMT493 470 kW PNP ...
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5 5 R14 R13 11, ...