SMARTDISCRETES Internally Clamped, Current Limited N Channel Logic Level Power MOSFET

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1 查 询 MLPN6 供 应 商 EMICONUCTOR TECHNICAL ATA Order this document by MLPN6CL/ MARTICRETE Internally Clamped, Current Limited N Channel Logic Level Power MOFET These MARTICRETE devices feature current limiting for short circuit protection, an integral gate to source clamp for E protection and gate to drain clamp for over voltage protection. No additional gate series resistance is required when interfacing to the output of a MCU, but a kω gate pulldown resistor is recommended to avoid a floating gate condition. The internal gate to source and gate to drain clamps allow the devices to be applied without use of external transient suppression components. The gate to source clamp protects the MOFET input from electrostatic gate voltage stresses up to. kv. The gate to drain clamp protects the MOFET drain from drain avalanche stresses that occur with inductive loads. This unique design provides voltage clamping that is essentially independent of operating temperature. The MLPN6CL is fabricated using Motorola s MARTICRETE technology which combines the advantages of a power MOFET output device with on chip protective circuitry. This approach offers an economical means for providing additional functions that protect a power MOFET in harsh automotive and industrial environments. MARTICRETE devices are specified over a wide temperature range from 5 C to 5 C. Temperature Compensated ate to rain Clamp Limits Voltage tress Applied to the evice and Protects the Load From Overvoltage Integrated E iode Protection Controlled witching Minimizes RFI Low Threshold Voltage Enables Interfacing Power Loads to Microprocessors Motorola Preferred evice VOLTAE CLAMPE CURRENT LIMITIN MOFET 6 VOLT (CLAMPE) R(on) =.75 OHM R R MAXIMUM RATIN (TC = 5 C unless otherwise noted) Rating ymbol Value Unit rain to ource Voltage V Clamped Vdc rain to ate Voltage (R =. MΩ) VR Clamped Vdc ate to ource Voltage Continuous V ± Vdc rain Current Continuous rain Current ingle Pulse I IM elf limited.8 Total Power issipation P Watts Adc Electrostatic ischarge Voltage (Human Body Model) E. kv Operating and torage Junction Temperature Range TJ, Tstg 5 to 5 C THERMAL CHARACTERITIC Thermal Resistance, Junction to Case Thermal Resistance, Junction to Ambient Maximum Lead Temperature for oldering Purposes, /8 from case RθJC RθJA. 6.5 C/W TL 6 C UNCLAMPE RAIN TO OURCE AVALANCHE CHARACTERITIC ingle Pulse rain to ource Avalanche Energy (tarting TJ = 5 C, I =. A, L = mh) (Figure 6) EA 8 mj CAE A 6, tyle 5 TO AB MARTICRETE is a trademark of Motorola, Inc. Preferred devices are Motorola recommended choices for future use and best overall value. REV Motorola, Inc. TMO 996 Power MOFET Transistor evice ata

2 ELECTRICAL CHARACTERITIC (TJ = 5 C unless otherwise noted) Characteristic ymbol Min Typ Max Unit OFF CHARACTERITIC rain to ource ustaining Voltage (Internally Clamped) (I = ma, V = ) (I = ma, V =, TJ = 5 C) V(BR) Vdc Zero ate Voltage rain Current (V = 5 V, V = ) (V = 5 V, V =, TJ = 5 C) I µadc ate Body Leakage Current (V = 5. V, V = ) (V = 5. V, V =, TJ = 5 C) I µadc ON CHARACTERITIC* ate Threshold Voltage (I = 5 µa, V = V) (I = 5 µa, V = V, TJ = 5 C) V(th) Vdc tatic rain to ource On Resistance (I =. A, V =. V) (I =. A, V = 5. V) (I =. A, V =. V, TJ = 5 C) (I =. A, V = 5. V, TJ = 5 C) R(on) Ohms Forward Transconductance (I =. A, V = V) gf.. mhos tatic ource to rain iode Voltage (I =. A, V = ) V..5 Vdc tatic rain Current Limit (V = 5. V, V = V) (V = 5. V, V = V, TJ = 5 C) I(lim) A REITIVE WITCHIN CHARACTERITIC* Turn On elay Time td(on).. µs Rise Time tr. 6. (V = 5 V, I =. A, Turn Off elay Time V = 5. V, R = 5 Ohms) td(off). 6. Fall Time tf. 5. * Indicates Pulse Test: Pulse Width µs, uty Cycle.%. TJ = 5 C V 7.5 V 5 C I, RAIN CURRENT (AMP) V 6 V V = V 8 V V I, RAIN CURRENT (AMP) 5 C TJ = 5 C 6 8 V, RAIN TO OURCE VOLTAE (VOLT) Figure. Output Characteristics 6 8 V, ATE TO OURCE VOLTAE (VOLT) Figure. Transfer Function Motorola TMO Power MOFET Transistor evice ata

3 THE MARTICRETE CONCEPT From a standard power MOFET process, several active and passive elements can be obtained that provide on chip protection to the basic power device. uch elements require only a small increase in silicon area and/or the addition of one masking layer to the process. The resulting device exhibits significant improvements in ruggedness and reliability as well as system cost reduction. The MARTICRETE device functions can now provide an economical alternative to smart power ICs for power applications requiring low on resistance, high voltage and high current. These devices are designed for applications that require a rugged power switching device with short circuit protection that can be directly interfaced to a microcontroller unit (MCU). Ideal applications include automotive fuel injector driver, incandescent lamp driver or other applications where a high in rush current or a shorted load condition could occur. OPERATION IN THE CURRENT LIMIT MOE The amount of time that an unprotected device can withstand the current stress resulting from a shorted load before its maximum junction temperature is exceeded is dependent upon a number of factors that include the amount of heatsinking that is provided, the size or rating of the device, its initial junction temperature, and the supply voltage. Without some form of current limiting, a shorted load can raise a device s junction temperature beyond the maximum rated operating temperature in only a few milliseconds. Even with no heatsink, the MLPN6CL can withstand a shorted load powered by an automotive battery ( to Volts) for almost a second if its initial operating temperature is under C. For longer periods of operation in the current limited mode, device heatsinking can extend operation from several seconds to indefinitely depending on the amount of heatsinking provided. HORT CIRCUIT PROTECTION AN THE EFFECT OF TEMPERATURE The on chip circuitry of the MLPN6CL offers an integrated means of protecting the MOFET component from high in rush current or a shorted load. As shown in the schematic diagram, the current limiting feature is provided by an NPN transistor and integral resistors R and R. R senses the current through the MOFET and forward biases the NPN transistor s base as the current increases. As the NPN turns on, it begins to pull gate drive current through R, dropping the gate drive voltage across it, and thus lowering the voltage across the gate to source of the power MOFET and limiting the current. The current limit is temperature dependent as shown in Figure, and decreases from about. Amps at 5 C to about. Amps at 5 C. ince the MLPN6CL continues to conduct current and dissipate power during a shorted load condition, it is important to provide sufficient heatsinking to limit the device junction temperature to a maximum of 5 C. The metal current sense resistor R adds about. ohms to the power MOFET s on resistance, but the effect of temperature on the combination is less than on a standard MOFET due to the lower temperature coefficient of R. The on resistance variation with temperature for gate voltages of and 5 Volts is shown in Figure 5. Back to back polysilicon diodes between gate and source provide E protection to greater than kv, HBM. This on chip protection feature eliminates the need for an external Zener diode for systems with potentially heavy line transients. I(lim), RAIN CURRENT (AMP) R(on), ON REITANCE (OHM) R(on), ON REITANCE (OHM) V = 5 V V = 7.5 V Figure. I(lim) Variation With Temperature 6 8 V, ATE TO OURCE VOLTAE (VOLT) C TJ = 5 C Figure. R(on) Variation With ate To ource Voltage V = V V = 5 V Figure 5. On Resistance Variation With Temperature I = A 5 C I = A Motorola TMO Power MOFET Transistor evice ata

4 WA, INLE PULE AVALANCHE ENERY (mj) BV(), RAIN OURCE UTAININ VOLTAE (VOLT) Figure 6. ingle Pulse Avalanche Energy versus Junction Temperature Figure 7. rain ource ustaining Voltage Variation With Temperature FORWAR BIAE AFE OPERATIN AREA The FBOA curves define the maximum drain to source voltage and drain current that a device can safely handle when it is forward biased, or when it is on, or being turned on. Because these curves include the limitations of simultaneous high voltage and high current, up to the rating of the device, they are especially useful to designers of linear systems. The curves are based on a case temperature of 5 C and a maximum junction temperature of 5 C. Limitations for repetitive pulses at various case temperatures can be determined by using the thermal response curves. Motorola Application Note, AN569, Transient Thermal Resistance eneral ata and Its Use provides detailed instructions. UTY CYCLE OPERATION When operating in the duty cycle mode, the maximum drain voltage can be increased. The maximum operating temperature is related to the duty cycle (C) by the following equation: TC = (V x I x C x RθCA) + TA The maximum value of V applied when operating in a duty cycle mode can be approximated by: 6 V = 5 TC I(lim) x C x RθJC MAXIMUM C VOLTAE CONIERATION The maximum drain to source voltage that can be continuously applied across the MLPN6CL when it is in current limit is a function of the power that must be dissipated. This power is determined by the maximum current limit at maximum rated operating temperature (.8 A at 5 C) and not the R(on). The maximum voltage can be calculated by the following equation: Vsupply = (5 TA) I(lim) (RθJC + RθCA) where the value of RθCA is determined by the heatsink that is being used in the application. I, RAIN CURRENT (AMP) I(lim) MAX I(lim) MIN.5 ms 5 ms.6 EVICE/POWER LIMITE. R(on) LIMITE. V = 5 V INLE PULE. TC = 5 C 6 6 V, RAIN TO OURCE VOLTAE (VOLT) Figure 8. Maximum Rated Forward Bias afe Operating Area (MLPN6CL) dc ms Motorola TMO Power MOFET Transistor evice ata

5 r(t), EFFECTIVE TRANIENT THERMAL REITANCE (NORMALIZE) = t. t INLE PULE UTY CYCLE, =t/t t, TIME (ms) RθJC(t) = r(t) RθJC RθJC(t) =. C/W Max Curves Apply for Power Pulse Train hown Read Time at t TJ(pk) TC = P(pk) RθJC(t) P(pk) Figure 9. Thermal Response (MLPN6CL) V ton toff RL Vout td(on) tr 9% td(off) tf 9% PULE ENERATOR Rgen z = 5 Ω Vin UT OUTPUT, Vout INVERTE % 5Ω 5 Ω INPUT, Vin % 5% PULE WITH 9% 5% Figure. witching Test Circuit Figure. witching Waveforms ACTIVE CLAMPIN MARTICRETE technology can provide on chip realization of the popular gate to source and gate to drain Zener diode clamp elements. Until recently, such features have been implemented only with discrete components which consume board space and add system cost. The MARTICRETE technology approach economically melds these features and the power chip with only a slight increase in chip area. In practice, back to back diode elements are formed in a polysilicon region monolithicly integrated with, but electrically isolated from, the main device structure. Each back to back diode element provides a temperature compensated voltage element of about 7. volts. As the polysilicon region is formed on top of silicon dioxide, the diode elements are free from direct interaction with the conduction regions of the power device, thus eliminating parasitic electrical effects while maintaining excellent thermal coupling. To achieve high gate to drain clamp voltages, several voltage elements are strung together; the MLPN6CL uses 8 such elements. Customarily, two voltage elements are used to provide a. volt gate to source voltage clamp. For the MLPN6CL, the integrated gate to source voltage elements provide greater than. kv electrostatic voltage protection. The avalanche voltage of the gate to drain voltage clamp is set less than that of the power MOFET device. As soon as the drain to source voltage exceeds this avalanche voltage, the resulting gate to drain Zener current builds a gate voltage across the gate to source impedance, turning on the power device which then conducts the current. ince virtually all of the current is carried by the power device, the gate to drain voltage clamp element may be small in size. This technique of establishing a temperature compensated drain to source sustaining voltage (Figure 7) effectively removes the possibility of drain to source avalanche in the power device. The gate to drain voltage clamp technique is particularly useful for snubbing loads where the inductive energy would otherwise avalanche the power device. An improvement in ruggedness of at least four times has been observed when inductive energy is dissipated in the gate to drain clamped conduction mode rather than in the more stressful gate to source avalanche mode. Motorola TMO Power MOFET Transistor evice ata 5

6 TYPICAL APPLICATION: INJECTOR RIVER, OLENOI, LAMP, RELAY COIL The MLPN6CL has been designed to allow direct interface to the output of a microcontrol unit to control an isolated load. No additional series gate resistance is required, but a kω gate pulldown resistor is recommended to avoid a floating gate condition in the event of an MCU failure. The internal clamps allow the device to be used without any external transistent suppressing components. V MCU VBAT MLPN6CL PACKAE IMENION H Q Z L V B N A K F T U R J C T EATIN PLANE CAE A 6 IUE Y TYLE 5: PIN. ATE. RAIN. OURCE. RAIN NOTE:. IMENIONIN AN TOLERANCIN PER ANI Y.5M, 98.. CONTROLLIN IMENION: INCH.. IMENION Z EFINE A ZONE WHERE ALL BOY AN LEA IRREULARITIE ARE ALLOWE. INCHE MILLIMETER IM MIN MAX MIN MAX A B C F H J K L N Q...5. R T U V.5.5 Z.8. 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 can and do vary in different applications. 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. hould 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: UA / EUROPE: Motorola Literature istribution; JAPAN: Nippon Motorola Ltd.; Tatsumi P JLC, Toshikatsu Otsuki, P.O. Box 9; Phoenix, Arizona F eibu Butsuryu Center, Tatsumi Koto Ku, Tokyo 5, Japan MFAX: RMFAX@ .sps.mot.com TOUCHTONE (6) 669 HON KON: Motorola emiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, INTERNET: NET.com 5 Ting Kok Road, Tai Po, N.T., Hong Kong Motorola TMO Power MOFET Transistor MLPN6CL/ evice ata