SI3400-D-GM Silicon Laboratories Inc, SI3400-D-GM Datasheet
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SI3400-D-GM
Specifications of SI3400-D-GM
Related parts for SI3400-D-GM
SI3400-D-GM Summary of contents
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... The Si3400 and Si3401 are available in low-profile, 20-pin QFN packages. While the Si3400 is designed for applications the Si3401 is optimized for higher power applications (up to approximately 15 W). See also “AN313: Using the Si3400/01 in High Power Applications” for more information ...
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... Si3400/Si3401 Functional Block Diagram VPOSF VPOSS CT1 CT2 SP1 SP2 VNEG 2 RDET RCL SSFT VDD Detection & Classification Hotswap Control & Common Hotswap Bias Switch & Current limit HSO PLOSS VSSA Rev. 0.9 ISOSSFT Switcher EROUT Control FB Switching SWO FET VSS1 ...
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... Section 1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 2. Typical Application Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 3. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.2. PD Hotswap Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.3. Switching Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4. Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5. Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 6. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 Si3400/Si3401 Rev. 0.9 Page 3 ...
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... Si3400/Si3401 1. Electrical Specifications Table 1. Absolute Maximum Ratings (DC) Type Voltage CT1 to CT2 SP1 to SP2 2 VPOS HSO VSS1 or VSS2 SWO PLOSS to VPOS RDET RCL SSFT to VPOS EROUT to VSS1, VSS2, or VSSA FB to VPOS RIMAX to VSS1, VSS2, or VSSA VSS1 to VSS2 or VSSA VDD to VSS1, VSS2, or VSSA ...
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... Note: Unless otherwise noted, all voltages referenced to VNEG. All minimum and maximum specifications are guaranteed and apply across the recommended operating conditions. Typical values apply at nominal supply voltage and ambient temperature unless otherwise noted. 1 Description 2 Symbol Min VPORT 2.8 TA –40 Rev. 0.9 Si3400/Si3401 Rating Unit – – –0 –0 –0 –0 –80 to 0.7 –0 – – ...
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... This higher current limit remains active until the UVLO lower limit has been tripped or until the hotswap switch is sufficiently current-limited to cause a foldback of the HSO voltage. 5. See “AN296: Using the Si3400/01 PoE PD Controller in Isolated and Non-Isolated Designs” for more information. 6. Applies to non-isolated applications only (VOUT on schematic in Figure 1). ...
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... This higher current limit remains active until the UVLO lower limit has been tripped or until the hotswap switch is sufficiently current-limited to cause a foldback of the HSO voltage. 5. See “AN296: Using the Si3400/01 PoE PD Controller in Isolated and Non-Isolated Designs” for more information. 6. Applies to non-isolated applications only (VOUT on schematic in Figure 1). ...
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... CT2 Si3400 D1 SP1 Si3401 SP2 SWO RDET EROUT RCL C6 R4 Using the Si3400/01 PoE PD Controller in Isolated and Non-Isolated Toler. Rating 20% 100 V Switcher supply capacitor. Several paral- lel capacitors are used for lower ESR. 20% 100 V PD input supply capacitor. 20 Switcher load capacitor - 1000 µF in par- allel with and X5R 22 µ ...
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... Transformer PS2911 Optocoupler TLV431 Voltage reference D2 D3 SWO C8 CT1 ISOSSFT CT2 Si3400 VDD SP1 R2 Si3401 SP2 EROUT RDET R3 RCL C5 C7 Using the Si3400/01 PoE PD Controller in Isolated and Non-Isolated Value Toler. Rating 15 µF 20% 100 V 0.1 µF 20% 100 0.1 µF 20 µF 20 ...
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... Si3401 are compatible with compliant and legacy PSEs because they use two levels for the hotswap current limits. By setting the initial inrush current limit to a low level based on the Si3400 or Si3401 minimizes the current drawn from either a compliant or legacy PSE during startup. After powering up, the ...
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... PSE to determine the proper power requirements of the PD. When the PSE presents a fixed voltage between 15.5 V enables and 20 the PD, the Si3400 and Si3401 assert the class current from VPOS through the RCL resistor. Rev. 0.9 Si3400/Si3401 ...
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... The Si3400 and Si3401 stay in a high-level current limit mode until the input voltage drops below the UVLO turn- off threshold or excessive power is dissipated in the hotswap switch ...
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... Due to integration of the diode bridges, the Si3400 and Si3401 are able to instantaneously detect the removal of the line voltage and provide that early warning signal to the PD application ...
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... In the isolated mode, a capacitor connected between pins ISOSSFT and VSSA slowly ramps the duty cycle clamp in the PWM circuit. Tie this pin to VDD if not used. 3.3.2. Switching Regulator Operation The switching regulator of the Si3400 and Si3401 is constant-frequency, pulse-width-modulated (PWM), and controller integrated with ...
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... Pin Descriptions ISOSSFT Table 11. Si3400 and Si3401 Pin Descriptions (Top View) Pin# Name 1 EROUT Error-amplifier output and PWM input; directly connected to opto-coupler in isolated application. Soft-start output pin ramps voltage across external soft-start capacitor to allow switcher to ramp 2 SSFT output slowly. 3 VDD 5 V supply rail for switcher; provides drive for opto-coupler. ...
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... Si3400/Si3401 5. Package Outline Figure 5 illustrates the package details for the Si3400 and Si3401. Table 12 lists the values for the dimensions shown in the illustration. Figure 5. 20-Lead Quad Flat No-Lead Package (QFN) Dimension aaa bbb ccc ddd Notes: 1. All dimensions shown are in millimeters (mm) unless otherwise noted. ...
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... Add an “R” at the end of the part number to denote tape and reel option. 3. Refer to “AN313: Using the Si3400/01 in High Power Applications” and “AN314: Power Combining Circuit for PoE for up to 18.5 W Output” for more information about using the Si3400 and Si3401 in higher power applications. ...
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... Si3400/Si3401 OCUMENT HANGE IST Revision 0.3 to Revision 0.4 Updated Figure 2 on page 9. R9 now correctly connected to VNEG; RIMAX now connects to VDD. Added Table 6, “Package Thermal Characteristics,” on page 7. Updated Figure 3 on page 10. Updated Table 4 on page 6. Updated switcher frequency specification to 350 kHz. ...
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... N : OTES Si3400/Si3401 Rev. 0.9 19 ...
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... Si3400/Si3401 C I ONTACT NFORMATION Silicon Laboratories Inc. 400 West Cesar Chavez Austin, TX 78701 Tel: 1+(512) 416-8500 Fax: 1+(512) 416-9669 Toll Free: 1+(877) 444-3032 Email: PoEinfo@silabs.com Internet: www.silabs.com The information in this document is believed to be accurate in all respects at the time of publication but is subject to change without notice. ...