N Channel Enhancement Mode Silicon Gate

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1 SEMICONDUCTOR TECHNICAL DATA Order this document by MMFT55VL/D N Channel Enhancement Mode Silicon Gate TMOS V is a new technology designed to achieve an on resistance area product about one half that of standard MOSFETs. This new technology more than doubles the present cell density of our 5 and 6 volt TMOS devices. Just as with our TMOS E FET designs, TMOS V is designed to withstand high energy in the avalanche and commutation modes. Designed for low voltage, high speed switching applications in power supplies, converters and power motor controls, these devices are particularly well suited for bridge circuits where diode speed and commutating safe operating areas are critical and offer additional safety margin against unexpected voltage transients. New Features of TMOS V On resistance Area Product about One half that of Standard MOSFETs with New Low Voltage, Low RDS(on) Technology Faster Switching than E FET Predecessors Features Common to TMOS V and TMOS E FETS Avalanche Energy Specified IDSS and VDS(on) Specified at Elevated Temperature Static Parameters are the Same for both TMOS V and TMOS E FET Available in 2 mm Tape & Reel Use MMFT55VLT to order the 7 inch/ unit reel Use MMFT55VLT to order the inch/4 unit reel MAXIMUM RATINGS (TC = 25 C unless otherwise noted) Rating Symbol Value Unit Drain to Source Voltage VDSS 6 Vdc Drain to Gate Voltage (RGS =. MΩ) VDGR 6 Vdc Gate to Source Voltage Continuous Gate to Source Voltage Non repetitive (tp ms) Drain Current Continuous Drain Current C Drain Current Single Pulse (tp µs) Total TA = 25 C mounted on sq. Drain pad on FR 4 bd material Total TA = 25 C mounted on.7 sq. Drain pad on FR 4 bd material Total TA = 25 C mounted on min. Drain pad on FR 4 bd material Derate above 25 C VGS VGSM ID ID IDM ± 5 ± PD Operating and Storage Temperature Range TJ, Tstg 55 to 75 C Single Pulse Drain to Source Avalanche Energy Starting (VDD = 25 Vdc, VGS = 5. Vdc, Peak IL =.4 Apk, L = mh, RG = 25 Ω ) Thermal Resistance Junction to Ambient on sq. Drain pad on FR 4 bd material Junction to Ambient on.7 sq. Drain pad on FR 4 bd material Junction to Ambient on min. Drain pad on FR 4 bd material Maximum Lead Temperature for Soldering Purposes, /8 from case for seconds TL 26 C EAS RθJA RθJA RθJA Vdc Vpk Adc Apk Watts mw/ C Designer s Data for Worst Case Conditions The Designer s Data Sheet permits the design of most circuits entirely from the information presented. SOA Limit curves representing boundaries on device characteristics are given to facilitate worst case design. E FET, Designer s, and TMOS V are trademarks of Motorola, Inc. TMOS is a registered trademark of Motorola, Inc. G D S TM TMOS POWER FET.5 AMPERES 6 VOLTS RDS(on) =.4 OHM 2 4 CASE 8E 4, Style TO 26AA mj C/W REV Motorola, Inc. TMOS 996 Power MOSFET Transistor Device Data

2 ELECTRICAL CHARACTERISTICS ( unless otherwise noted) OFF CHARACTERISTICS Characteristic Symbol Min Typ Max Unit Drain to Source Breakdown Voltage (Cpk 2.) () (VGS = Vdc, ID =.25 madc) Temperature Coefficient (Positive) Zero Gate Voltage Drain Current (VDS = 6 Vdc, VGS = Vdc) (VDS = 6 Vdc, VGS = Vdc, TJ = 5 C) V(BR)DSS Gate Body Leakage Current (VGS = ± 5 Vdc, VDS = Vdc) IGSS nadc IDSS 6 65 Vdc mv/ C µadc ON CHARACTERISTICS () Gate Threshold Voltage (Cpk 2.) () (VDS = VGS, ID = 25 µadc) Threshold Temperature Coefficient (Negative) Static Drain to Source On Resistance (Cpk 2.) () (VGS = 5. Vdc, ID =.75 Adc) VGS(th) Vdc mv/ C RDS(on).25.4 Ohm Drain to Source On Voltage (VGS = 5. Vdc, ID =.5 Adc) (VGS = 5. Vdc, ID =.75 Adc, TJ = 5 C) VDS(on) Forward Transconductance (VDS = 8. Vdc, ID =.5 Adc) gfs..5 mhos Vdc DYNAMIC CHARACTERISTICS Input Capacitance Output Capacitance Transfer Capacitance (VDS = 25 Vdc, VGS = Vdc, f =. MHz) Ciss 5 49 pf Coss 5 Crss 29 6 SWITCHING CHARACTERISTICS (2) Turn On Delay Time td(on) ns Rise Time Turn Off Delay Time Fall Time (VDD = Vdc, ID =.5 Adc, tr 8 4 VGS = 5. Vdc, RG = 9. Ω) td(off) 5 7 tf 22 4 Gate Charge QT 9. nc SOURCE DRAIN DIODE CHARACTERISTICS Forward On Voltage () (VDS = 48 Vdc, ID =.5 Adc, Q. VGS = 5. Vdc) Q2 4. (IS =.5 Adc, VGS = Vdc) (IS =.5 Adc, VGS = Vdc, TJ = 5 C) Q.5 Reverse Recovery Time trr 4 ns VSD (IS =.5 Adc, VGS = Vdc, ta 29 dis/dt = A/µs) tb 2 Reverse Recovery Stored Charge QRR.66 µc.2 Vdc INTERNAL PACKAGE INDUCTANCE Internal Drain Inductance (Measured from the drain lead.25 from package to center of die) LD 4.5 nh Internal Source Inductance (Measured from the source lead.25 from package to source bond pad) LS 7.5 nh () Pulse Test: Pulse Width µs, Duty Cycle 2%. (2) Switching characteristics are independent of operating junction temperature. () Reflects typical values. Max limit Typ C pk = x SIGMA 2 Motorola TMOS Power MOSFET Transistor Device Data

3 TYPICAL ELECTRICAL CHARACTERISTICS I D, DRAIN CURRENT (AMPS) V 4.5 V.5 V VDS, DRAIN TO SOURCE VOLTAGE (VOLTS) V 2.5 V 2 V I D, DRAIN CURRENT (AMPS) 4 VDS V C.5 TJ = 55 C C VGS, GATE TO SOURCE VOLTAGE (VOLTS) Figure. On Region Characteristics Figure 2. Transfer Characteristics R DS(on), DRAIN TO SOURCE RESISTANCE (OHMS).25 VGS = 5 V TJ = C C C R DS(on), DRAIN TO SOURCE RESISTANCE (OHMS) VGS = V V ID, DRAIN CURRENT (AMPS) ID, DRAIN CURRENT (AMPS) Figure. On Resistance versus Drain Current and Temperature Figure 4. On Resistance versus Drain Current and Gate Voltage R DS(on), DRAIN TO SOURCE RESISTANCE (NORMALIZED) VGS = 5 V ID =.75 A TJ, JUNCTION TEMPERATURE ( C) 75 IDSS, LEAKAGE (na) VGS = V C VDS, DRAIN TO SOURCE VOLTAGE (VOLTS) Figure 5. On Resistance Variation with Temperature Figure 6. Drain To Source Leakage Current versus Voltage Motorola TMOS Power MOSFET Transistor Device Data

4 POWER MOSFET SWITCHING Switching behavior is most easily modeled and predicted by recognizing that the power MOSFET is charge controlled. The lengths of various switching intervals ( t) are determined by how fast the FET input capacitance can be charged by current from the generator. The published capacitance data is difficult to use for calculating rise and fall because drain gate capacitance varies greatly with applied voltage. Accordingly, gate charge data is used. In most cases, a satisfactory estimate of average input current (IG(AV)) can be made from a rudimentary analysis of the drive circuit so that t = Q/IG(AV) During the rise and fall time interval when switching a resistive load, VGS remains virtually constant at a level known as the plateau voltage, VSGP. Therefore, rise and fall times may be approximated by the following: tr = Q2 x RG/(VGG VGSP) tf = Q2 x RG/VGSP where VGG = the gate drive voltage, which varies from zero to VGG RG = the gate drive resistance and Q2 and VGSP are read from the gate charge curve. During the turn on and turn off delay times, gate current is not constant. The simplest calculation uses appropriate values from the capacitance curves in a standard equation for voltage change in an RC network. The equations are: td(on) = RG Ciss In [VGG/(VGG VGSP)] td(off) = RG Ciss In (VGG/VGSP) The capacitance (Ciss) is read from the capacitance curve at a voltage corresponding to the off state condition when calculating td(on) and is read at a voltage corresponding to the on state when calculating td(off). At high switching speeds, parasitic circuit elements complicate the analysis. The inductance of the MOSFET source lead, inside the package and in the circuit wiring which is common to both the drain and gate current paths, produces a voltage at the source which reduces the gate drive current. The voltage is determined by Ldi/dt, but since di/dt is a function of drain current, the mathematical solution is complex. The MOSFET output capacitance also complicates the mathematics. And finally, MOSFETs have finite internal gate resistance which effectively adds to the resistance of the driving source, but the internal resistance is difficult to measure and, consequently, is not specified. The resistive switching time variation versus gate resistance (Figure 9) shows how typical switching performance is affected by the parasitic circuit elements. If the parasitics were not present, the slope of the curves would maintain a value of unity regardless of the switching speed. The circuit used to obtain the data is constructed to minimize common inductance in the drain and gate circuit loops and is believed readily achievable with board mounted components. Most power electronic loads are inductive; the data in the figure is taken with a resistive load, which approximates an optimally snubbed inductive load. Power MOSFETs may be safely operated into an inductive load; however, snubbing reduces switching losses. C, CAPACITANCE (pf) VDS = V VGS = V 9 8 Ciss 7 6 Crss 5 4 Ciss 2 Coss Crss VGS VDS GATE TO SOURCE OR DRAIN TO SOURCE VOLTAGE (VOLTS) Figure 7. Capacitance Variation 4 Motorola TMOS Power MOSFET Transistor Device Data

5 V GS, GATE TO SOURCE VOLTAGE (VOLTS) Q QT Q2 Q VDS QT, TOTAL CHARGE (nc) VGS ID =.5 A V DS, DRAIN TO SOURCE VOLTAGE (VOLTS) t, TIME (ns) VDD = V ID =.5 A VGS = 5 V td(off) tf tr td(on) RG, GATE RESISTANCE (OHMS) Figure 8. Gate To Source and Drain To Source Voltage versus Total Charge Figure 9. Resistive Switching Time Variation versus Gate Resistance DRAIN TO SOURCE DIODE CHARACTERISTICS.6.4 VGS = V, SOURCE CURRENT (AMPS) IS VSD, SOURCE TO DRAIN VOLTAGE (VOLTS) Figure. Diode Forward Voltage versus Current SAFE OPERATING AREA The Forward Biased Safe Operating Area curves define the maximum simultaneous drain to source voltage and drain current that a transistor can handle safely when it is forward biased. Curves are based upon maximum peak junction temperature and a case temperature (TC) of 25 C. Peak repetitive pulsed power limits are determined by using the thermal response data in conjunction with the procedures discussed in AN569, Transient Thermal Resistance General Data and Its Use. Switching between the off state and the on state may traverse any load line provided neither rated peak current (IDM) nor rated voltage (VDSS) is exceeded and the transition time (tr,tf) do not exceed µs. In addition the total power averaged over a complete switching cycle must not exceed (TJ(MAX) TC)/(RθJC). A Power MOSFET designated E FET can be safely used in switching circuits with unclamped inductive loads. For reliable operation, the stored energy from circuit inductance dissipated in the transistor while in avalanche must be less than the rated limit and adjusted for operating conditions differing from those specified. Although industry practice is to rate in terms of energy, avalanche energy capability is not a constant. The energy rating decreases non linearly with an increase of peak current in avalanche and peak junction temperature. Although many E FETs can withstand the stress of drain to source avalanche at currents up to rated pulsed current (IDM), the energy rating is specified at rated continuous current (ID), in accordance with industry custom. The energy rating must be derated for temperature as shown in the accompanying graph (Figure ). Maximum energy at currents below rated continuous ID can safely be assumed to equal the values indicated. Motorola TMOS Power MOSFET Transistor Device Data 5

6 SAFE OPERATING AREA I D, DRAIN CURRENT (AMPS). VGS = 5 V SINGLE PULSE TC = 25 C ms 5 ms s ms RDS(on) LIMIT THERMAL LIMIT dc PACKAGE LIMIT VDS, DRAIN TO SOURCE VOLTAGE (VOLTS) E AS, SINGLE PULSE DRAIN TO SOURCE AVALANCHE ENERGY (mj) TJ, STARTING JUNCTION TEMPERATURE ( C) ID =.5 A 75 Figure. Maximum Rated Forward Biased Safe Operating Area Figure 2. Maximum Avalanche Energy versus Starting Junction Temperature Rthja(t), EFFECTIVE TRANSIENT THERMAL RESISTANCE... D = SINGLE PULSE..E 5.E 4.E.E 2.E.E+.E+ t, TIME (s) Figure. Thermal Response.E+2.E+ IS di/dt ta trr tb TIME tp.25 IS IS Figure 4. Diode Reverse Recovery Waveform 6 Motorola TMOS Power MOSFET Transistor Device Data

7 INFORMATION FOR USING THE SOT 22 SURFACE MOUNT PACKAGE MINIMUM RECOMMENDED FOOTPRINT FOR SURFACE MOUNTED APPLICATIONS Surface mount board layout is a critical portion of the total design. The footprint for the semiconductor packages must be the correct size to insure proper solder connection interface between the board and the package. With the correct pad geometry, the packages will self align when subjected to a solder reflow process inches mm SOT 22 The power dissipation of the SOT 22 is a function of the drain pad size. This can vary from the minimum pad size for soldering to a pad size given for maximum power dissipation. Power dissipation for a surface mount device is determined by TJ(max), the maximum rated junction temperature of the die, RθJA, the thermal resistance from the device junction to ambient, and the operating temperature, TA. Using the values provided on the data sheet for the SOT 22 package, PD can be calculated as follows: PD = T J(max) TA RθJA The values for the equation are found in the maximum ratings table on the data sheet. Substituting these values into the equation for an ambient temperature TA of 25 C, one can calculate the power dissipation of the device which in this case is 94 milliwatts. PD = 75 C 25 C 59 C/W = 94 milliwatts The 59 C/W for the SOT 22 package assumes the use of the recommended footprint on a glass epoxy printed circuit board to achieve a power dissipation of 94 milliwatts. There are other alternatives to achieving higher power dissipation from the SOT 22 package. One is to increase the area of the drain pad. By increasing the area of the drain pad, the power SOT 22 POWER DISSIPATION dissipation can be increased. Although one can almost double the power dissipation with this method, one will be giving up area on the printed circuit board which can defeat the purpose of using surface mount technology. A graph of RθJA versus drain pad area is shown in Figure 7. R JA, Thermal Resistance, Junction to Ambient ( C/W) θ Board Material =.625 G /FR 4, 2 oz Copper.8 Watts.25 Watts*.5 Watts *Mounted on the DPAK footprint A, Area (square inches) TA = 25 C Figure 5. Thermal Resistance versus Drain Pad Area for the SOT 22 Package (Typical) Another alternative would be to use a ceramic substrate or an aluminum core board such as Thermal Clad. Using a board material such as Thermal Clad, an aluminum core board, the power dissipation can be doubled using the same footprint. Motorola TMOS Power MOSFET Transistor Device Data 7

8 Prior to placing surface mount components onto a printed circuit board, solder paste must be applied to the pads. A solder stencil is required to screen the optimum amount of solder paste onto the footprint. The stencil is made of brass or The melting temperature of solder is higher than the rated temperature of the device. When the entire device is heated to a high temperature, failure to complete soldering within a short time could result in device failure. Therefore, the following items should always be observed in order to minimize the thermal stress to which the devices are subjected. Always preheat the device. The delta temperature between the preheat and soldering should be C or less.* When preheating and soldering, the temperature of the leads and the case must not exceed the maximum temperature ratings as shown on the data sheet. When using infrared heating with the reflow soldering method, the difference shall be a maximum of C. SOLDER STENCIL GUIDELINES SOLDERING PRECAUTIONS stainless steel with a typical thickness of.8 inches. The stencil opening size for the SOT 22 package should be the same as the pad size on the printed circuit board, i.e., a : registration. The soldering temperature and time shall not exceed 26 C for more than seconds. When shifting from preheating to soldering, the maximum temperature gradient shall be 5 C or less. After soldering has been completed, the device should be allowed to cool naturally for at least three minutes. Gradual cooling should be used as the use of forced cooling will increase the temperature gradient and result in latent failure due to mechanical stress. Mechanical stress or shock should not be applied during cooling * Soldering a device without preheating can cause excessive thermal shock and stress which can result in damage to the device. 8 Motorola TMOS Power MOSFET Transistor Device Data

9 For any given circuit board, there will be a group of control settings that will give the desired heat pattern. The operator must set temperatures for several heating zones, and a figure for belt speed. Taken together, these control settings make up a heating profile for that particular circuit board. On machines controlled by a computer, the computer remembers these profiles from one operating session to the next. Figure 8 shows a typical heating profile for use when soldering a surface mount device to a printed circuit board. This profile will vary among soldering systems but it is a good starting point. Factors that can affect the profile include the type of soldering system in use, density and types of components on the board, type of solder used, and the type of board or substrate material being used. This profile shows temperature versus time. The TYPICAL SOLDER HEATING PROFILE line on the graph shows the actual temperature that might be experienced on the surface of a test board at or near a central solder joint. The two profiles are based on a high density and a low density board. The Vitronics SMD convection/infrared reflow soldering system was used to generate this profile. The type of solder used was 62/6/2 Tin Lead Silver with a melting point between C. When this type of furnace is used for solder reflow work, the circuit boards and solder joints tend to heat first. The components on the board are then heated by conduction. The circuit board, because it has a large surface area, absorbs the thermal energy more efficiently, then distributes this energy to the components. Because of this effect, the main body of a component may be up to degrees cooler than the adjacent solder joints. 2 C 5 C C 5 C STEP PREHEAT ZONE RAMP STEP 2 VENT SOAK STEP HEATING ZONES 2 & 5 RAMP DESIRED CURVE FOR HIGH MASS ASSEMBLIES 5 C C STEP 4 HEATING ZONES & 6 SOAK 6 C 4 C DESIRED CURVE FOR LOW MASS ASSEMBLIES STEP 5 HEATING ZONES 4 & 7 SPIKE 7 C STEP 6 VENT SOLDER IS LIQUID FOR 4 TO 8 SECONDS (DEPENDING ON MASS OF ASSEMBLY) STEP 7 COOLING 25 TO 29 C PEAK AT SOLDER JOINT TIME ( TO 7 MINUTES TOTAL) TMAX Figure 6. Typical Solder Heating Profile Motorola TMOS Power MOSFET Transistor Device Data 9

10 PACKAGE DIMENSIONS.8 () L S H G A F 4 2 D B C M K J NOTES:. DIMENSIONING AND TOLERANCING PER ANSI Y4.5M, CONTROLLING DIMENSION: INCH. INCHES MILLIMETERS DIM MIN MAX MIN MAX A B C D F G H J K L M S STYLE : PIN. GATE 2. DRAIN. SOURCE 4. DRAIN CASE 8E 4 ISSUE H Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Typical parameters which may be provided in Motorola data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including Typicals must be validated for each customer application by customer s technical experts. Motorola does not convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury or death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall indemnify and hold Motorola and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that Motorola was negligent regarding the design or manufacture of the part. Motorola and are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal Opportunity/Affirmative Action Employer. How to reach us: USA / EUROPE / Locations Not Listed: Motorola Literature Distribution; JAPAN: Nippon Motorola Ltd.; Tatsumi SPD JLDC, 6F Seibu Butsuryu Center, P.O. Box 292; Phoenix, Arizona or Tatsumi Koto Ku, Tokyo 5, Japan MFAX: RMFAX@ .sps.mot.com TOUCHTONE ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, INTERNET: NET.com 5 Ting Kok Road, Tai Po, N.T., Hong Kong MMFT55VL/D Motorola TMOS Power MOSFET Transistor Device Data