A Product Line of Diodes Incorporated ZXGD3108N8 40V ACTIVE OR-ING MOSFET CONTROLLER IN SO8 Description Features ZXGD3108N8 is a 40V Active OR-ing MOSFET controller designed for driving a very low RDS(ON) Power MOSFET as an ideal diode. This • Active OR’ing MOSFET Controller for High- or Low-Side PSU • Ideal Diode to Reduce Forward Voltage Drop replaces the standard rectifier to reduce the forward voltage drop and • -3mV typical Turn-Off Threshold with ±2mV Tolerance overall increase the power transfer efficiency. • • The ZXGD3108N8 can be used on both high-side and low-side power supply units (PSU) with rails up to ±40V. It enables very low RDS(ON) 40V Drain Voltage Rating 25V VCC Rating • <5mW Standby Power with Quiescent Supply Current <400µA • <600ns Turn-Off Time to Minimize Reverse Current MOSFETs to operate as ideal diodes as the turn-off threshold is • Totally Lead-Free & Fully RoHS compliant (Notes 1 & 2) only -3mV with ±2mV tolerance. In the typical 12V configuration, the • Halogen and Antimony free. “Green” Device (Note 3) standby power consumption is <5mW as the low quiescent supply Mechanical Data current is <400µA. During PSU fault condition, the OR‘ing Controller detects the power reduction and rapidly turns off the MOSFET in • <600ns to block reverse current flow and avoid the common bus • voltage dropping. Case: SO-8 Case material: Molded Plastic. “Green” Molding Compound UL Flammability Rating 94V-0 Applications • Moisture Sensitivity: Level 1 per J-STD-020 • Terminals: Finish - Matte Tin Plated Leads, Solderable per Active OR‘ing Controller in: MIL-STD-202, Method 208 • (N + 1) Redundant Power Supplies • Telecom and Networking • Data Centers and Servers • Weight: 0.074 grams (approximate) Power Supply SO-8 DNC DRAIN GND DNC GND Vcc GATE Vcc Pin Name DNC GND GATE DRAIN VCC Pin Function Do Not Connect Power Ground Gate Drive Drain Sense Power Supply Top View Ordering Information (Note 4) Product ZXGD3108N8TC Notes: Marking ZXGD 3108 Reel size (inches) 13 Tape width (mm) 12 Quantity per reel 2,500 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. 2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green" and Lead-free. 3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and <1000ppm antimony compounds. 4. For packaging details, go to our website at http://www.diodes.com/products/packages.html. Marking Information ZXGD 3108 YY WW ZXGD3108N8 Document Number DS36530 Rev. 1 - 2 ZXGD 3108 YY WW = Product Type Marking Code, Line 1 = Product Type Marking Code, Line 2 = Year (ex: 14 = 2014) = Week (01 - 53) 1 of 10 www.diodes.com May 2014 © Diodes Incorporated A Product Line of Diodes Incorporated ZXGD3108N8 Absolute Maximum Ratings (Voltage relative to GND, @ TA = +25°C, unless otherwise specified.) Characteristic Symbol Supply Voltage Value 25 VCC Unit V Drain Pin Voltage VD -3 to 40 V Gate Output Voltage VG -3 to VCC + 3 V Gate Driver Peak Source Current Gate Driver Peak Sink Current ISOURCE 2 A ISINK 5 A Value 490 Unit Thermal Characteristics (@ TA = +25°C, unless otherwise specified.) Characteristic Symbol (Note 5) 3.92 655 (Note 6) Power Dissipation Linear derating factor PD 720 (Note 7) 5.76 785 (Note 8) 6.28 (Note 5) (Note 6) (Note 7) (Note 8) (Note 9) Thermal Resistance, Junction to Ambient Thermal Resistance, Junction to Lead mW mW/°C 5.24 RθJL 255 191 173 159 135 TJ, TSTG -50 to +150 RθJA Operating and Storage Temperature Range °C /W °C /W °C ESD Ratings (Note 10) Characteristic Electrostatic Discharge - Human Body Model Electrostatic Discharge - Machine Model Notes: Symbol ESD HBM ESD MM Value 2,000 200 Unit V V JEDEC Class 3A B 5. For a device surface mounted on minimum recommended pad layout FR4 PCB with high coverage of single sided 1oz copper, in still air conditions; the device is measured when operating in a steady-state condition. 6. Same as note (5), except pins 2 & 3 (GND) and pins 5 & 6 (VCC) are both connected to separate 5mm x 5mm 1oz copper heat-sinks. 7. Same as note (6), except both heat-sinks are 10mm x 10mm. 8. Same as note (6), except both heat-sinks are 15mm x 15mm. 9. Thermal resistance from junction to solder-point at the end of each lead on pins 2 & 3 (GND) and pins 5 & 6 (VCC). 10. Refer to JEDEC specification JESD22-A114 and JESD22-A11 Max Power Dissipation (W) Thermal Derating Curve 0.8 15mm x 15mm 0.7 10mm x 10mm 0.6 0.5 5mm x 5mm 0.4 Minimum Layout 0.3 0.2 0.1 0.0 0 20 40 60 80 100 120 140 160 Junction Temperature (°C) Derating Curve ZXGD3108N8 Document Number DS36530 Rev. 1 - 2 2 of 10 www.diodes.com May 2014 © Diodes Incorporated A Product Line of Diodes Incorporated ZXGD3108N8 Electrical Characteristics (@ VCC = 12V, TA = +25°C, unless otherwise specified.) Characteristic Symbol Min Typ Max Unit Test Condition Input Supply Operating Supply Voltage Quiescent Current VCC 4 — 20 V IQ — 200 400 µA -0.6V ≤ VDRAIN ≤ 30V ISOURCE — 0.66 — ISINK — 3.3 — A CL = 47nF ISOURCE 1 — — A VGATE = 5V & VDRAIN = -1V ISINK 1.8 — — A VGATE = 5V & VDRAIN = 1V VT -5 -3 -1 mV VG(off) — 0.1 0.3 VG 9 9.2 VG(off) — 0.1 0.3 VG 3 3.2 — VG(off) — 0.1 0.3 VDRAIN ≥ -8mV & VCC = 20V VG 19 19.2 — VDRAIN = -8mV & VCC = 20V td(rise) — 400 — tr — 695 — td(fall) — 400 — tf — 131 — Gate Driver Gate Peak Source Current Gate Peak Sink Current Gate Peak Source Current (Note 11) Gate Peak Sink Current (Note 11) Detector under DC condition Turn-off Threshold Voltage VG ≤1V VDRAIN ≥ 0mV VDRAIN = -8mV Gate Output Voltage VDRAIN ≥ 0mV & VCC = 4V V VDRAIN = -8mV & VCC = 4V Load: 50nF capacitor connected in parallel with 50kΩ resistor Switching Performance Turn-On Propagation Delay Gate Rise Time Turn-Off Propagation Delay Gate Fall Time Note: ns CL = 47nF Rise and fall measured 10% to 90% Refer to application test circuit below 11. Measured under pulsed conditions. Pulse width = 300μs. Duty cycle ≤ 2%. Pin Functions Pin Number Pin Name Pin Function and Description 1, 7 DNC Do Not Connect Leave pin floating. 2, 3 GND Ground Connect this pin to the MOSFET source terminal and ground reference point. 4 GATE Gate Drive This pin sources (ISOURCE) and sinks (ISINK) current into the MOSFET gate. The turn on time of the MOSFET can be programmed through an external gate resistor (RG). 5, 6 VCC 8 DRAIN Power Supply This supply pin should be closely decoupled to ground with a X7R type capacitor. Drain Sense Connect this pin to the MOSFET drain terminal to detect the change in drain-source voltage. ZXGD3108N8 Document Number DS36530 Rev. 1 - 2 DNC DRAIN GND DNC GND Vcc GATE Vcc 3 of 10 www.diodes.com May 2014 © Diodes Incorporated A Product Line of Diodes Incorporated ZXGD3108N8 Layout Considerations The GATE pin should be close to the MOSFET gate to minimize trace resistance and inductance to maximize switching performance. Whilst the VCC to GND pin needs an X7R type capacitor closely decoupling the supply. Trace widths should be maximized in the high current paths through the MOSFET and ground return in order to minimize the effects of circuit resistance and inductance; also, the ground return loop should be as short as possible. For thermal consideration, the main heat path is from pins 2 & 3 (GND) and pins 5 & 6 (VCC). For best thermal performance, the copper area connected to pins 2 & 3 (GND) and pins 5 & 6 (VCC) should be maximised. Active OR’ing or (N+1) Redundancy Application Critical systems require fault-tolerant power supply that can be achieved by paralleling two or more PSUs into (N+1) redundancy configuration. During normal operation, usually all PSUs equally share the load for maximum reliability. If one of the PSU is unplugged or fails, then the other PSUs fully support the load. To avoid the faulty PSU from affecting the common bus, then an OR-ing rectifier blocks the reverse current flow into the faulty PSU. Likewise during hot-swapping, the OR’ing rectifiers isolate a PSU’s discharged output capacitors from the common bus. As the load current is in the tens of amps then a standard rectifier has a significant forward voltage drop. This both wastes power and significantly drops the potential on low voltage rails. Hence, very low RDS(ON) Power MOSFETs can replace the standard rectifiers and the ZXGD3108 controls the MOSFET as an ideal diode. Functional Block Diagram Vcc ZXGD3108 + DRAIN - Differential amplifier Driver GATE Threshold voltage GND The device is comprised of a differential amplifier and high current driver. The differential amplifier acts as a detector and monitors the DRAIN-toGND pin voltage difference. When this difference is less than the threshold voltage (VT) then a positive output voltage approaching VCC is given on the GATE pin. Conversely, when the DRAIN-to-GND pin voltage difference is greater than VT, then GATE pin voltage is rapidly reduced towards the GND voltage. ZXGD3108N8 Document Number DS36530 Rev. 1 - 2 4 of 10 www.diodes.com May 2014 © Diodes Incorporated A Product Line of Diodes Incorporated ZXGD3108N8 Typical Application Circuits The focus application of the ZXGD3108 OR‘ing Controller is for Redundant Low-Side -12V Power Supply Rail. Example of the ZXGD3108 OR‘ing Controller in a Redundant High-Side +12V Power Supply Rail with the addition of a VCC Supply. ZXGD3108N8 Document Number DS36530 Rev. 1 - 2 5 of 10 www.diodes.com May 2014 © Diodes Incorporated A Product Line of Diodes Incorporated ZXGD3108N8 Operation in Typical Application The ZXGD3108 operation is described step-by-step with reference to the typical application circuits and the timing diagram below: 1. The ZXGD3108 differential amplifier monitors the MOSFET’s drain-source voltage (VDS). 2. At system start up, the MOSFET body diode is forced to conduct current from the input PSU to the load and VDS is approximately -0.6V as 3. measured by the differential amplifier between DRAIN-to-GND pins. As VDS < VT (threshold voltage), then the differential amplifier outputs a positive voltage approaching VCC with respect to GND. This feeds the driver stage from which the GATE pin voltage rises towards VCC. 4. The sourcing current out of the GATE pin drives the MOSFET gate to enhance the channel and turn it on. 5. 6. If a short condition occurs on the input PSU, it causes the MOSFET VDS to increase. When VDS > VT, then the differential amplifier’s output goes to GND and the driver stage rapidly pulls the GATE pin voltage to GND, turning off the MOSFET channel. This prevents high reverse current flow from the load to the PSU which could pull down the common bus voltage causing catastrophic system failure. ZXGD3108N8 Document Number DS36530 Rev. 1 - 2 6 of 10 www.diodes.com May 2014 © Diodes Incorporated A Product Line of Diodes Incorporated ZXGD3108N8 20 18 16 Capacitive load only 14 12 10 8 6 VCC = 5V 4 2 0 -10 -9 -8 -7 -6 -5 VG Gate Voltage (V) VG Gate Voltage (V) Typical Electrical Characteristics (@ TA = +25°C, unless otherwise specified.) VCC = 20V VCC = 12V VCC = 10V -4 -3 VD Drain Voltage (mV) -2 -1 0 20 18 16 Capacitive load and 50kΩ pull down resistor 14 12 10 8 6 VCC = 5V 4 2 0 -10 -9 -8 -7 -6 -5 VD Drain Voltage (mV) VG Gate Voltage (V) Ta = 125°C Ta = 85°C 6 Ta = 150°C 4 VCC = 12V 2 50kΩ pull down 0 -3.0 -2.5 Ta = -50°C -2.0 -1.5 -1.0 -0.5 0.0 VD Drain Voltage (mV) -4 -3 -2 -1 0 0.0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 -1.4 -1.6 -1.8 -2.0 -50 VCC = 12V VG = 1V 50kΩ pull down 0 50 100 150 Temperature (°C) Transfer Characteristic Drain Sense Voltage vs Temperature 500 2000 Supply Current (mA) VCC = 12V Switching Time (ns) VCC = 10V Transfer Characteristic 10 Ta = 25°C VCC = 12V VD Drain Voltage (mV) Transfer Characteristic 8 VCC = 20V CL=47nF 1600 T on = td1 + tr 1200 T off = td2 + tf 800 400 -50 VCC = 20V f=250kHz 400 VCC = 10V 300 VCC = 12V 200 VCC = 5V 100 0 -25 0 25 50 75 Temperature (°C) 100 125 150 Switching vs Temperature ZXGD3108N8 Document Number DS36530 Rev. 1 - 2 0 20 40 60 Capacitance (nF) 80 100 Supply Current vs Capacitive Load 7 of 10 www.diodes.com May 2014 © Diodes Incorporated A Product Line of Diodes Incorporated ZXGD3108N8 Typical Electrical Characteristics (cont.) (@ TA = +25°C, unless otherwise specified.) 8 V=12V CL=47nF VD 6 150 100 10 100 50 0 4 -50 2 -100 0 -2 -1.0 -0.5 0.0 0.5 1.0 1.5 -150 2.0 50 V=12V CL=47nF 6 0 VD 4 -50 2 -100 0 -2 -1.0 Time (us) Switch Off Speed VG 8 Drain Voltage (mV) VG 12 GateVoltage (V) Gate Voltage (V) 10 150 DrainVoltage (mV) 12 -0.5 0.0 0.5 1.0 1.5 -150 2.0 Time (us) Switch On Speed Time (ns) 900 Ton = td1 + tr 600 300 T off = td2 + tf 1 10 100 Capacitance (nF) 53 52 51 50 -5 -4 0.8 Isink Isource 0.6 0.4 -3 -2 V=12V CL=47nF -1 0.2 0.0 -1 0 1 2 3 4 source current Time scale(us) 5 0 Gate Drive Sink Current (A) VCC=12V 1200 Gate Drive source Current (A) Sink current Time scale (us) 54 1.0 Gate Drive Current Switching vs Capacitive Load VCC=12V Supply Current (mA) Peak Drive Current (A) 4 -Isink 2 Isource 0 1 10 100 CL=100nF CL=10nF 10 0.1 10 CL=1nF 100 1000 10000 100000 Frequency (Hz) Gate Current vs Capacitive Load Document Number DS36530 Rev. 1 - 2 CL=4.7nF VCC=12V 1 Capacitance (nF) ZXGD3108N8 CL=47nF 100 Supply Current vs Frequency 8 of 10 www.diodes.com May 2014 © Diodes Incorporated A Product Line of Diodes Incorporated ZXGD3108N8 Package Outline Dimensions 0.254 Please see AP02002 at http://www.diodes.com/datasheets/ap02002.pdf for latest version. E1 E A1 L Gauge Plane Seating Plane Detail ‘A’ h 7°~9° 45° Detail ‘A’ A2 A A3 b e D SO-8 Dim Min Max A 1.75 A1 0.10 0.20 A2 1.30 1.50 A3 0.15 0.25 b 0.3 0.5 D 4.85 4.95 E 5.90 6.10 E1 3.85 3.95 e 1.27 Typ h 0.35 L 0.62 0.82 0° 8° θ All Dimensions in mm Suggested Pad Layout Please see AP02001 at http://www.diodes.com/datasheets/ap02001.pdf for the latest version. X C1 C2 Dimensions X Y C1 C2 Value (in mm) 0.60 1.55 5.4 1.27 Y ZXGD3108N8 Document Number DS36530 Rev. 1 - 2 9 of 10 www.diodes.com May 2014 © Diodes Incorporated A Product Line of Diodes Incorporated ZXGD3108N8 IMPORTANT NOTICE DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS DOCUMENT, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION). Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further notice to this document and any product described herein. Diodes Incorporated does not assume any liability arising out of the application or use of this document or any product described herein; neither does Diodes Incorporated convey any license under its patent or trademark rights, nor the rights of others. Any Customer or user of this document or products described herein in such applications shall assume all risks of such use and will agree to hold Diodes Incorporated and all the companies whose products are represented on Diodes Incorporated website, harmless against all damages. Diodes Incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized sales channel. Should Customers purchase or use Diodes Incorporated products for any unintended or unauthorized application, Customers shall indemnify and hold Diodes Incorporated and its representatives harmless against all claims, damages, expenses, and attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized application. Products described herein may be covered by one or more United States, international or foreign patents pending. Product names and markings noted herein may also be covered by one or more United States, international or foreign trademarks. This document is written in English but may be translated into multiple languages for reference. Only the English version of this document is the final and determinative format released by Diodes Incorporated. LIFE SUPPORT Diodes Incorporated products are specifically not authorized for use as critical components in life support devices or systems without the express written approval of the Chief Executive Officer of Diodes Incorporated. As used herein: A. Life support devices or systems are devices or systems which: 1. are intended to implant into the body, or 2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in significant injury to the user. B. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or to affect its safety or effectiveness. Customers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support devices or systems, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products and any use of Diodes Incorporated products in such safety-critical, life support devices or systems, notwithstanding any devices- or systems-related information or support that may be provided by Diodes Incorporated. Further, Customers must fully indemnify Diodes Incorporated and its representatives against any damages arising out of the use of Diodes Incorporated products in such safety-critical, life support devices or systems. Copyright © 2014, Diodes Incorporated www.diodes.com ZXGD3108N8 Document Number DS36530 Rev. 1 - 2 10 of 10 www.diodes.com May 2014 © Diodes Incorporated