SI3460 Silicon Laboratories, SI3460 Datasheet
SI3460
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SI3460 Summary of contents
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... IEEE 802.3af-compliant Power Sourcing Equipment (PSE). Designed to minimize system cost and ease of implementation in embedded PSE endpoint (switches) or midspan (power injector) applications, the Si3460 operates directly from input supply and integrates a digital PWM-based dc-dc converter for generating the –48 V PSE output supply. The IEEE-required Powered Device (PD) detection feature uses a robust 3-point algorithm to avoid false detection events ...
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... RST STATUS 2 PWM DC/DC OTP Osc. Controller: Memory Current Limiting, State Short Circuit Machine Protection Control Config. & LED Controller: I/F Detection Classification Disconnect Figure 1. Si3460 Block Diagram Preliminary Rev. 0.4 GATE 250KHZ UVLO, VSENSE ISENSE PSE CTRL1 CTRL2 DETA Datasheet pdf - http://www.DataSheet4U.net/ ...
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... Section 1. Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 2. Si3460-EVB Application Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 2.1. Si3460-EVB Performance Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 3. Si3460 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 4. Si3460-EVB Performance Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 4.1. PSE Timing Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 4.2. DC-DC Converter Performance Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 5. Si3460-EVB Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.1. Reset State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 5.2. Operating Mode Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.3. Operating Mode Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6 ...
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... Si3460-EVB Performance Characteristics When implemented according to the recommended external components and layout guidelines for the Si3460- EVB, the Si3460 enables the following performance specifications in single-port PSE applications. Please refer to the Si3460-EVB User’s Guide and schematics for details. Table 1. Selected Electrical Specifications (Si3460-EVB) ...
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... Table 1. Selected Electrical Specifications (Si3460-EVB) Parameter Protection and Current Control Overload current threshold Overload current limit Overload time Output power at overload Disconnect current Efficiency System efficiency Symbol Test Condition I All class levels CUT Output = 100 Ω across V I LIM OUT Output = 100 Ω ...
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... Si3460 3. Si3460 Electrical Specifications The following specifications apply to the Si3460 controller. Refer to Tables and 7, the Si3460-EVB User’s Guide, and schematics for additional details about the electrical specifications of the Si3460-EVB reference design. Description Operating temperature range Thermal impedance VDD input supply voltage *Note: VDD = 2.7 to 3.6 V, – ...
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... µ Any digital pin IH V Any digital pin Preliminary Rev. 0.4 Si3460 Min Typ Max 0.8 x VDD — — VDD – 0.1 — — — 0.7 x VDD — — — 0.6 — — 0.1 — 0.4 x VDD — 0.7 x VDD — ...
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... Si3460 4. Si3460-EVB Performance Characteristics When implemented in accordance with the recommended external components and layout guidelines, the Si3460 controller enables the following typical performance characteristics in single-port PSE applications. Refer to the Si3460-EVB applications note, schematics, and user's guide for more details. Parameter ...
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... PSE Timing Characteristics When implemented in accordance with the recommended external components and layout guidelines, the Si3460 controller enables the following typical performance characteristics in single-port PSE applications. Refer to the Si3460-EVB applications note, schematics, and user's guide for more details. Description Endpoint detection delay ...
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... Si3460 4.2. DC-DC Converter Performance Characteristics The dc-dc converter utilizes a digital control loop architecture operating at 250 kHz. The complete converter is comprised of the Si3460 controller and the external components in the Si3460-EVB schematics. The performance specifications in Table 7 are typical for the Si3460-EVB reference design. Parameter DC-DC Controller Performance Characteristics ...
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... Si3460-EVB reference design. Refer to the Si3460-EVB User’s Guide and schematics for descriptions in the following sections. 5.1. Reset State At powerup or if reset is held low, the Si3460 inactive state with the PWM turned off (the switcher FET, M1, is off) and the pass FET, M2, is off. 5.2. Operating Mode Configuration At powerup, the Si3460 reads the voltage on the STATUS pin, which is set by a resistor divider from V ground ...
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... The STATUS LED is continuously lit when power is applied. If the output power exceeds the level determined by the initial voltage of the STATUS pin, the Si3460 will declare an error and shut down the port, flashing the LED rapidly to indicate the error (for either two seconds or until reset as determined by the initial voltage on the STATUS pin) ...
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... Si3460 will declare a PD disconnect, and the dc-dc converter clock (250 kHz) and FET M1 will be turned off. As set by the initial voltage on the STATUS pin, the Si3460 will then automatically resume the detection process after 250 ms for "Endpoint mode" and two seconds for "Midspan mode." The difference in these two backoff timings is specified by the IEE 802 ...
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... The input power supply should be rated for at least 25% higher power level than the output power level chosen. This is primarily to account for the 75 to 80% nominal efficiency performance of the Si3460-EVB reference design. For example, to support a Class 0 PSE, for example, the input supply should be capable of supplying 19.25 W (15 ...
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... Si3460 Pin Descriptions Si3460 pin functionality is described in Table 10. Note that the information applies to the Si3460 device pins, while the Si3460-EVB User’s Guide describes the inputs and outputs of the evaluation system. The electrical characteristics of the Si3460-EVB are summarized in Table 1, “Si3460-EVB Performance Characteristics Summary,” ...
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... GND 16 Table 10. Si3460 Pin Functionality (Continued) Pin Type Active low reset input. When low (to GND), places the Si3460 device into an inactive state. The dc-dc converter is disabled. Digital input When pulled high, the device begins the detection process sequence. The dc-dc begins to function after a valid R ture is detected, indicating a valid PD has been detected ...
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... Add “R” to part number for tape and reel option (e.g. Si3460-X-GMR). 3. The ordering part number above is not the same as the device mark. The first line of the device mark is “3460”. ...
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... Si3460 9. Package Outline: 11-Pin QFN Figure 5 illustrates the package details for the Si3460. Table 11 lists the values for the dimensions shown in the illustration. The Si3460 is packaged in an industry-standard, 3x3 mm, RoHS-compliant, Pb-free, 11-pin QFN package Bottom View Side E View ...
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... Solder Paste Mask 0.35 mm 0. 0.50 mm 0. 0. 0.60 mm 0. Figure 6. Solder Paste Mask Preliminary Rev. 0.4 Si3460 0. Datasheet pdf - http://www.DataSheet4U.net/ ...
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... Si3460 9.2. PCB Landing Pattern 0.35 mm 0. 0. Figure 7. Typical QFN-11 Landing Diagram Preliminary Rev. 0.4 Datasheet pdf - http://www.DataSheet4U.net/ ...
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... Line 1 is the part number; line 2 is the lot code, and line 3 is the date code. The Lot ID Code on the top side of the device package can be used for decoding device revision information. On Si3460 devices, the silicon revision letter is the first letter of the Lot ID Code on the second line of the device mark. Figure 8 shows how to find the Lot ID Code on the top side of the device package for production devices ...
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... Si3460 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. ...