SI3402-A-GM Silicon Laboratories Inc, SI3402-A-GM Datasheet
SI3402-A-GM
Specifications of SI3402-A-GM
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SI3402-A-GM Summary of contents
Page 1
... The Si3402 is available in a low-profile, 20-pin QFN package. While the Si3402 is designed for applications can be used for higher power applications (up to approximately 15 W). See also “AN313: Using the Si3401/2 in High Power Applications” for more information ...
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... Si3402 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. 1.1 ISOSSFT PWM Control EROUT and EMI FB Limiting Switching ...
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... Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 2. Typical Application Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 3. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.2. PD Hotswap Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.3. Switching Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4. Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5. Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 6. Recommended Land Pattern for the Si3402 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 7. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 Rev. 1.1 Si3402 Page 3 ...
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... Si3402 1. Electrical Specifications Table 1. Recommended Operating Conditions Description |CT1 – CT2| or |SP1 – SP2| Ambient Operating Temperature 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 ...
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... Exposure to absolute maximum rating conditions for extended periods may adversely affect device reliability. 2. VPOS is equal to VPOSF and VPOSS tied together for test condition purposes. 1 (Continued) Description Rev. 1.1 Si3402 Rating Unit 0 to 100 –400 to 400 –400 to 400 ...
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... For more information regarding system-level surge tolerance, refer to “AN315: Robust Electrical Surge Immunity for PoE PDs through Integrated Protection”. 3. Designs must be compliant with the PCB layout and external component recommendations outlined in the Si3402 EVB User Guide and AN296 Deatherage and D. Jones, “Multiple Factors Trigger Cable Discharge Events in Ethernet LANs,” Electronic Design Dec ...
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... UVLO Turn On 1 Transient Surge VPORT < VPORT = 57 V Class 0 Class 1 Class 2 Class 3 Class < VPORT < Inrush Operating 36 V < VPORT < ISOSSFT connected to VDD DC Avg. 6 Output voltage tolerance @ VOUT Rev. 1.1 Si3402 Min Typ Max Unit 2.7 — — 22 — — — — 79 — ...
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... Si3402 Table 5. Electrical Characteristics (Continued) Parameter VDD Accuracy @ 0.8 mA Softstart Charging Current Thermal Shutdown Thermal Shutdown Hysteresis Notes: 1. Transient surge defined in IEC60060 as a 1000 V impulse of either polarity applied to CT1–CT2 or SP1–SP2. The shape of the impulse shall have a 300 ns full rise time and a 50 µs half fall time with 201 source impedance. ...
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... X5R 22 µF for lower ESR. 20 VDD bypass capacitor. 10 Softstart capacitor. 10 Compensation capacitor. 10 Compensation capacitor. 1% 1/16 W Detection resistor. 1% 1/16 W Feedback resistor divider. 1% 1/16 W Feedback resistor divider. 1% 1/16 W Feedback compensation resistor. 100 V Schottky diode; part no. PDS5100. 20% 3.5 A Coilcraft part no. DO5010333. Rev. 1.1 Si3402 Notes 9 ...
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... Resistor 36.5 k R7 Resistor 12.1 k R8 Resistor D1 Diode D2 Diode D3 Diode T1 Transformer PS2911 Optocoupler TLV431 Voltage reference SWO C8 CT1 ISOSSFT CT2 VDD Si3402 SP1 R2 SP2 EROUT RDET RCL Value Toler. Rating 15 µF 20% 100 V 0.1 µF 20% 100 220 nF 10 0.1 µF 20 µ ...
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... Functional Description The Si3402 consists of two major functions: a hotswap controller/interface and a complete modulated switching regulator (controller and power FET). 3.1. Overview The hotswap interface of the Si3402 provides the complete front end of an 802.3-compliant PD. The Si3402 also includes two full diode bridges, a transient ...
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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 and 20 the PD, the Si3402 asserts the class current from VPOS through the RCL resistor. The resistor values associated with each class are shown in Table 11 ...
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... UVLO turn-on threshold, the Si3402 begins to turn on the internal hotswap power MOSFET. The switcher supply capacitor begins to charge up under the current limit control of the Si3402, and the HSO pin transitions from VPOS to VNEG. The Si3402 includes hysteretic UVLO circuits to maintain power to the load until the input voltage falls below the UVLO turn-off threshold ...
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... Due to integration of the diode bridges, the Si3402 is able to instantaneously detect the removal of the line voltage and provide that early warning signal to the PD application. The PLOSS pin is an open drain output that pulls up to VPOS when a line voltage greater than applied ...
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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 not used. 3.3.2. Switching Regulator Operation The switching regulator of the Si3402 is constant- frequency, pulse-width-modulated controller integrated with ...
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... Si3402 4. Pin Descriptions ISOSSFT Table 12. Si3402 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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... Package Outline Figure 5 illustrates the package details for the Si3402. Table 13 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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... Si3402 6. Recommended Land Pattern Figure 6. Si3402 Recommended Land Pattern Table 14. PCB Land Pattern Dimensions Symbol Notes: General 1. All dimensions shown are in millimeters (mm) unless otherwise noted. 2. Dimensioning and Tolerancing is per the ANSI Y14.5M-1994 specification. 3. This Land Pattern Design is based on the IPC-7351 guidelines. ...
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... Ordering Guide 1,2 Package Part Number Si3402-A-GM 20-pin QFN, Pb-free; RoHS compliant Notes: 1. “X” denotes product revision. 2. Add an “R” at the end of the part number to denote tape and reel option. 3. Refer to “AN313: Using the Si3401/2 in High Power Applications” and “AN314: Power Combining Circuit for PoE for up to 18.5 W Output” ...
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... Si3402 OCUMENT HANGE IST Revision 1.0 to Revision 1.1 Added "6. Recommended Land Pattern" on page 18. 20 Rev. 1.1 ...
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... N : OTES Rev. 1.1 Si3402 21 ...
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... Si3402 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 Please visit the Silicon Labs Technical Support web page: https://www.silabs.com/support/pages/contacttechnicalsupport.aspx and register to submit a technical support request. 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. ...