DISCRETE SEMICONDUCTORS DATA SHEET BLF278 VHF push-pull power MOS transistor Product Specification Supersedes data of October 1992 1996 Oct 21 Philips Semiconductors Product Specification VHF push-pull power MOS transistor FEATURES BLF278 PINNING - SOT262A1 • High power gain PIN SYMBOL • Easy power control 1 d1 drain 1 • Good thermal stability 2 d2 drain 2 • Gold metallization ensures excellent reliability. 3 g1 gate 1 4 g2 gate 2 5 s source APPLICATIONS DESCRIPTION • Broadcast transmitters in the VHF frequency range. DESCRIPTION 1 2 d Dual push-pull silicon N-channel enhancement mode vertical D-MOS transistor encapsulated in a 4-lead, SOT262A1 balanced flange package with two ceramic caps. The mounting flange provides the common source connection for the transistors. g s g 5 d 5 3 4 Top view MAM098 CAUTION The device is supplied in an antistatic package. The gate-source input must be protected against static discharge during transport or handling. Fig.1 Simplified outline and symbol. QUICK REFERENCE DATA RF performance at Th = 25 °C in a push-pull common source test circuit. f (MHz) VDS (V) PL (W) Gp (dB) ηD (%) CW, class-B 108 50 300 >20 >60 CW, class-C 108 50 300 typ. 18 typ. 80 CW, class-AB 225 50 250 >14 typ. 16 >50 typ. 55 MODE OF OPERATION WARNING Product and environmental safety - toxic materials This product contains beryllium oxide. The product is entirely safe provided that the BeO discs are not damaged. All persons who handle, use or dispose of this product should be aware of its nature and of the necessary safety precautions. After use, dispose of as chemical or special waste according to the regulations applying at the location of the user. It must never be thrown out with the general or domestic waste. 1996 Oct 21 2 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 LIMITING VALUES In accordance with the Absolute Maximum System (IEC 134). SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT Per transistor section VDS drain-source voltage − 110 V VGS gate-source voltage − ±20 V ID drain current (DC) Ptot total power dissipation Tstg Tj − 18 A − 500 W storage temperature −65 150 °C junction temperature − 200 °C up to Tmb = 25 °C total device; both sections equally loaded THERMAL CHARACTERISTICS SYMBOL PARAMETER CONDITIONS VALUE UNIT Rth j-mb thermal resistance from junction total device; both sections to mounting base equally loaded. max. 0.35 K/W Rth mb-h thermal resistance from mounting base to heatsink max. 0.15 K/W total device; both sections equally loaded. MRA988 100 MGE616 500 handbook, halfpage handbook, halfpage Ptot (W) ID (A) 400 (2) (1) (2) (1) 300 10 200 100 1 1 10 0 500 100 0 40 80 Total device; both sections equally loaded. (1) Current is this area may be limited by RDSon. (2) Tmb = 25 °C. 160 Total device; both sections equally loaded. (1) Continuous operation. (2) Short-time operation during mismatch. Fig.2 DC SOAR. 1996 Oct 21 120 Th (°C) VDS (V) Fig.3 Power derating curves. 3 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 CHARACTERISTICS Tj = 25 °C unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT Per transistor section V(BR)DSS drain-source breakdown voltage VGS = 0; ID = 50 mA 110 − − V IDSS drain-source leakage current VGS = 0; VDS = 50 V − − 2.5 mA IGSS gate-source leakage current VGS = ±20 V; VDS = 0 − − 1 µA VGSth gate-source threshold voltage VDS = 10 V; ID = 50 mA 2 − 4.5 V ∆VGS gate-source voltage difference of both sections VDS = 10 V; ID = 50 mA − − 100 mV gfs forward transconductance VDS = 10 V; ID = 5 A 4.5 6.2 − S gfs1/gfs2 forward transconductance ratio of both sections VDS = 10 V; ID = 5 A 0.9 − 1.1 RDSon drain-source on-state resistance VGS = 10 V; ID = 5 A − 0.2 0.3 Ω IDSX drain cut-off current VGS = 10 V; VDS = 10 V − 25 − A Cis input capacitance VGS = 0; VDS = 50 V; f = 1 MHz − 480 − pF Cos output capacitance VGS = 0; VDS = 50 V; f = 1 MHz − 190 − pF Crs feedback capacitance VGS = 0; VDS = 50 V; f = 1 MHz − 14 − pF Cd-f drain-flange capacitance − 5.4 − pF MGE623 0 MGE622 30 handbook, halfpage handbook, halfpage T.C. (mV/K) ID (A) −1 20 −2 −3 10 −4 −5 10−2 10−1 0 1 ID (A) 0 10 5 10 VGS (V) 15 VDS = 10 V. VDS = 10 V; Tj = 25 °C. Fig.4 Temperature coefficient of gate-source voltage as a function of drain current; typical values per section. 1996 Oct 21 Fig.5 4 Drain current as a function of gate-source voltage; typical values per section. Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 MGE621 400 MGE615 1200 handbook, halfpage handbook, halfpage RDSon (mΩ) C (pF) 300 800 200 Cis 400 100 Cos 0 0 0 50 100 150 0 Tj (°C) 20 VGS = 10 V; ID = 5 A. VGS = 0; f = 1 MHz. Fig.6 Fig.7 Drain-source on-state resistance as a function of junction temperature; typical values per section. MGE620 400 handbook, halfpage Crs (pF) 300 200 100 0 0 10 20 30 40 50 VDS (V) VGS = 0; f = 1 MHz. Fig.8 Feedback capacitance as a function of drain-source voltage; typical values per section. 1996 Oct 21 5 40 VDS (V) 60 Input and output capacitance as functions of drain-source voltage; typical values per section. Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 APPLICATION INFORMATION Class-B operation RF performance in CW operation in a common source push-pull test circuit. Th = 25 °C; Rth mb-h = 0.15 K/W unless otherwise specified. RGS = 4 Ω per section; optimum load impedance per section = 3.2 + j4.3 Ω (VDS = 50 V). f (MHz) VDS (V) IDQ (A) PL (W) Gp (dB) ηD (%) CW, class-B 108 50 2 × 0.1 300 >20 typ. 22 >60 typ. 70 CW, class-C 108 50 VGS = 0 300 typ. 18 typ. 80 MODE OF OPERATION Ruggedness in class-B operation The BLF278 is capable of withstanding a load mismatch corresponding to VSWR = 7 : 1 through all phases under the conditions: VDS = 50 V; f = 108 MHz at rated load power. 1996 Oct 21 6 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 MGE682 30 MGE683 80 handbook, halfpage handbook, halfpage ηD (%) Gp (dB) (2) (1) (1) 60 20 (2) (1) 40 (2) 10 20 0 0 200 400 PL (W) 0 600 0 200 400 PL (W) 600 Class-B operation; VDS = 50 V; IDQ = 2 × 0.1 A; f = 108 MHz; ZL = 3.2 + j4.3 Ω (per section); RGS = 4 Ω (per section). (1) Th = 25 °C. (2) Th = 70 °C. Class-B operation; VDS = 50 V; IDQ = 2 × 0.1 A; f = 108 MHz; ZL = 3.2 + j4.3 Ω (per section); RGS = 4 Ω (per section). (1) Th = 25 °C. (2) Th = 70 °C. Fig.9 Fig.10 Efficiency as a function of load power, typical values. Power gain as a function of load power, typical values. MGE684 600 handbook, halfpage PL (W) (1) 400 (2) 200 0 0 5 10 Pi (W) 15 Class-B operation; VDS = 50 V; IDQ = 2 × 0.1 A; f = 108 MHz; ZL = 3.2 + j4.3 Ω (per section); RGS = 4 Ω (per section). (1) Th = 25 °C. (2) Th = 70 °C. Fig.11 Load power as a function of input power, typical values. 1996 Oct 21 7 1996 Oct 21 +VDD1 50 Ω input R11 T1 handbook, full pagewidth C36 C2 8 IC1 C4 C1 R1 C5 L1 C8 C9 R3 C13 C12 D.U.T. C26 C17 R8 L12 C22 L11 C21 A C37 L2 C11 R7 R6 C10 C15 C14 R5 C19 R9 C18 L18 C25 C24 L16 C23 L15 L14 C28 L20 C29 L13 L17 L19 +VDD2 L10 C27 L9 C30 C32 C31 C34 R10 C33 MGE688 L23 ,, L22 ,, L21 50 Ω output VHF push-pull power MOS transistor Fig.12 Class-B test circuit at f = 108 MHz. C35 C7 L4 L6 L8 C6 L3 L5 L7 R4 ,,,, ,,,, ,,,, ,,,, C3 A R2 C16 +VDD1 C20 Philips Semiconductors Product Specification BLF278 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 List of components (see Figs 12 and 13). COMPONENT DESCRIPTION VALUE C1, C2, C33, C34 multilayer ceramic chip capacitor; note 1 22 pF, 500 V C3, C4 100 pF + 68 pF in parallel, 500 V multilayer ceramic chip capacitor; note 1 DIMENSIONS C5, C6, C28 film dielectric trimmer 5 to 60 pF C7 multilayer ceramic chip capacitor; note 1 2 × 100 pF + 1 × 120 pF in parallel, 500 V C8, C11, C12, C15, C16, C19, C36 multilayer ceramic chip capacitor 100 nF, 500 V C9, C10, C13, C14, C20, C25 multilayer ceramic chip capacitor; note 1 1 nF, 500 V C17, C18, C22, C23 multilayer ceramic chip capacitor; note 1 470 pF, 500 V C21, C24, C35 electrolytic capacitor 10 µF, 63 V C26 multilayer ceramic chip capacitor; note 1 2 × 15 pF + 1 × 18 pF in parallel, 500 V C27 multilayer ceramic chip capacitor; note 1 3 × 15 pF in parallel, 500 V C29 multilayer ceramic chip capacitor; note 1 2 × 18 pF + 1 × 15 pF in parallel, 500 V C30 film dielectric trimmer 2 to 18 pF C31, C32 multilayer ceramic chip capacitor; note 1 3 × 43 pF in parallel, 500 V L1, L2 stripline; note 2 43 Ω length 57.5 mm width 6 mm L3, L4 stripline; note 2 43 Ω length 29.5 mm width 6 mm L5, L6 stripline; note 2 43 Ω length 14 mm width 6 mm L7, L8 stripline; note 2 43 Ω length 6 mm width 6 mm L9, L10 stripline; note 2 43 Ω length 17.5 mm width 6 mm L11, L16 2 × grade 3B Ferroxcube wideband HF chokes in parallel L12, L15 4 turns enamelled 2 mm copper wire 85 nH length 13.5 mm int. dia. 10 mm leads 2 × 7 mm L13, L14 stripline; note 2 43 Ω length 19.5 mm width 6 mm 1996 Oct 21 CATALOGUE NO. 2222 809 08003 2222 852 47104 2222 809 09006 4312 020 36642 9 Philips Semiconductors Product Specification VHF push-pull power MOS transistor COMPONENT BLF278 DESCRIPTION VALUE DIMENSIONS L17, L18 stripline; note 2 43 Ω length 24.5 mm width 6 mm L19, L20 stripline; note 2 43 Ω length 66 mm width 6 mm L21, L23 stripline; note 2 50 Ω length 160 mm width 4.8 mm L22 semi-rigid cable; note 3 50 Ω ext. dia. 3.6 mm outer conductor length 160 mm R1 metal film resistor 10 Ω, 0.4 W R2, R7 10 turn potentiometer 50 kΩ R3, R6 metal film resistor 3 × 12.1 Ω in parallel, 0.4 W R4, R5 metal film resistor 10 Ω; 0.4 W R8, R9 metal film resistor 10 Ω ±5%, 1 W R10 metal film resistor 4 × 10 Ω in parallel, 1 W 5.11 kΩ, 1 W R11 metal film resistor IC1 voltage regulator 78L05 T1 1:1 Balun; 7 turns type 4C6 50 Ω coaxial cable wound around toroid 14 × 9 × 5 mm CATALOGUE NO. 4322 020 90770 Notes 1. American Technical Ceramics capacitor, type 100B or capacitor of same quality. 2. L1 to L10, L13, L14, L17 to L21 and L23 are striplines on a double copper-clad printed-circuit board, with fibre-glass PTFE dielectric (εr = 2.2), thickness 1⁄16 inch; thickness of copper sheet 2 × 35 µm. 3. L22 is soldered on to stripline L21. 1996 Oct 21 10 Philips Semiconductors Product Specification VHF push-pull power MOS transistor handbook, full pagewidth BLF278 150 130 strap strap strap strap strap 100 strap strap strap C20 IC1 V DD1 C11 R11 C36 50 Ω input T1 C35 slider R2 C12 C1 C3 R1 C2 C4 L3 L1 C5 C22 C8 R2 and R7 C9 C13 R3 R4 C7 L5 L7 C17 L4 C15 slider R7 L6 L8 C21 50 Ω output V DD1 L21 L12 C31 L9 C6 L2 L22 L11 C16 R8 L11 L10 R5 R6 L13 C26 L14 L15 C10 C14 C18 C23 L17 C27 L18 C33 L19 C29 C28 L20 C30 C34 C32 L23 V DD2 L16 R9 L16 C19 R10 C24 C25 MBC438 Dimensions in mm. The circuit and components are situated on one side of the PTFE fibre-glass board, the other side being fully metallized to serve as an earth. Earth connections are made by means of copper straps for a direct contact between upper and lower sheets. Fig.13 Printed-circuit board and component layout for 108 MHz class-B test circuit. 1996 Oct 21 11 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 MGE685 MGE686 8 2 handbook, halfpage handbook, halfpage Zi (Ω) ZL (Ω) ri RL 1 6 0 4 XL −1 2 xi −2 0 25 75 125 f (MHz) 25 175 75 125 f (MHz) 175 Class-B operation; VDS = 50 V; IDQ = 2 × 0.1 A; RGS = 4 Ω (per section); PL = 300 W. Class-B operation; VDS = 50 V; IDQ = 2 × 0.1 A; RGS = 4 Ω (per section); PL = 300 W. Fig.14 Input impedance as a function of frequency (series components), typical values per section. Fig.15 Load impedance as a function of frequency (series components), typical values per section. MGE687 30 handbook, halfpage Gp (dB) 20 handbook, halfpage 10 Zi ZL MBA379 0 25 75 125 f (MHz) 175 Class-B operation; VDS = 50 V; IDQ = 2 × 0.1 A; RGS = 4 Ω (per section); PL = 300 W. Fig.17 Power gain as a function of frequency, typical values per section. Fig.16 Definition of MOS impedance. 1996 Oct 21 12 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Class-AB operation RF performance in CW operation in a common source push-pull test circuit. Th = 25 °C; Rth mb-h = 0.15 K/W unless otherwise specified. RGS = 2.8 Ω per section; optimum load impedance per section = 0.74 + j2 Ω; (VDS = 50 V). MODE OF OPERATION f (MHz) VDS (V) IDQ (A) PL (W) Gp (dB) ηD (%) CW, class-AB 225 50 2 × 0.5 250 >14 typ. 16 >50 typ. 55 Ruggedness in class-AB operation The BLF278 is capable of withstanding a load mismatch corresponding to VSWR = 7 : 1 through all phases under the conditions: VDS = 50 V; f = 225 MHz at rated output power. 1996 Oct 21 13 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 MGE614 MGE612 60 20 handbook, halfpage handbook, halfpage (1) ηD (%) (2) Gp (dB) (1) (2) 40 10 20 0 0 0 100 200 0 300 PL (W) 100 200 PL (W) 300 Class-AB operation; VDS = 50 V; IDQ = 2 × 0.5 A; f = 225 MHz; ZL = 0.74 + j2 Ω (per section); RGS = 2.8 Ω (per section). (1) Th = 25 °C. (2) Th = 70 °C. Class-AB operation; VDS = 50 V; IDQ = 2 × 0.5 A; f = 225 MHz; ZL = 0.74 + j2 Ω (per section); RGS = 2.8 Ω (per section). (1) Th = 25 °C. (2) Th = 70 °C. Fig.18 Power gain as a function of load power, typical values. Fig.19 Efficiency as a function of load power, typical values. MGE613 400 handbook, halfpage PL (W) 300 (1) (2) 200 100 0 0 5 10 Pi (W) 15 Class-AB operation; VDS = 50 V; IDQ = 2 × 0.5 A; f = 225 MHz; ZL = 0.74 + j2 Ω (per section); RGS = 2.8 Ω (per section). (1) Th = 25 °C. (2) Th = 70 °C. Fig.20 Load power as a function of input power, typical values. 1996 Oct 21 14 50 Ω input 1996 Oct 21 L3 15 R11 C38 C2 IC1 C4 C1 R1 C3 A C5 C11 C37 L5 C36 R7 R6 C9 C13 C12 R5 D.U.T. L20 C18 C19 C27 C26 L17 C25 L16 L19 +VDD2 L13 C29 L21 C21 C28 L18 C30 ,,,, C20 L12 C17 R9 L15 C24 L14 ,,,, C16 C15 R8 C23 C22 C32 C31 C33 C34 R10 MGE617 L24 L23 ,, L22 ,, 50 Ω output VHF push-pull power MOS transistor Fig.21 Class-AB test circuit at f = 225 MHz. C35 C7 L7 L9 L11 C6 L6 L8 L10 ,,, ,,, L4 R4 C8 R3 C10 handbook, full pagewidth +VDD1 L2 ,,, ,,, L1 A R2 C14 +VDD1 Philips Semiconductors Product Specification BLF278 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 List of components (see Figs 21 and 22). COMPONENT DESCRIPTION VALUE DIMENSIONS CATALOGUE NO. C1, C2 multilayer ceramic chip capacitor; note 1 27 pF, 500 V C3, C4, C31, C32 multilayer ceramic chip capacitor; note 1 3 × 18 pF in parallel, 500 V C5 film dielectric trimmer 4 to 40 pF 2222 809 08002 C6, C30 film dielectric trimmer 2 to 18 pF 2222 809 09006 C7 multilayer ceramic chip capacitor; note 1 100 pF, 500 V C8, C9, C15, C18 MKT film capacitor 1 µF, 63 V 2222 371 11105 C10, C13, C14, C19, C36 multilayer ceramic chip capacitor 100 nF, 50 V 2222 852 47104 C11, C12 multilayer ceramic chip capacitor; note 1 2 × 1 nF in parallel, 500 V C16, C17 electrolytic capacitor 220 µF, 63 V C20 multilayer ceramic chip capacitor; note 1 3 × 33 pF in parallel, 500 V C21 film dielectric trimmer 2 to 9 pF C22, C27, C37, C38 multilayer ceramic chip capacitor; note 1 1 nF, 500 V C23, C26, C35 electrolytic capacitor 10 µF, 63 V C24, C25 multilayer ceramic chip capacitor; note 1 2 × 470 pF in parallel, 500 V C28 multilayer ceramic chip capacitor; note 1 2 × 10 pF + 1 × 18 pF in parallel, 500 V C29 multilayer ceramic chip capacitor; note 1 2 × 5.6 pF in parallel, 500 V C33, C34 multilayer ceramic chip capacitor; note 1 5.6 pF, 500 V L1, L3, L22, L24 stripline; note 2 50 Ω length 80 mm width 4.8 mm L2, L23 semi-rigid cable; note 3 50 Ω ext. dia. 3.6 mm outer conductor length 80 mm L4, L5 stripline; note 2 43 Ω length 24 mm width 6 mm L6, L7 stripline; note 2 43 Ω length 14.5 mm width 6 mm L8, L9 stripline; note 2 43 Ω length 4.4 mm width 6 mm L10, L11 stripline; note 2 43 Ω length 3.2 mm width 6 mm L12, L13 stripline; note 2 43 Ω length 15 mm width 6 mm 1996 Oct 21 16 2222 809 09005 Philips Semiconductors Product Specification VHF push-pull power MOS transistor COMPONENT BLF278 DESCRIPTION VALUE DIMENSIONS L14, L17 2 × grade 3B Ferroxcube wideband HF chokes in parallel L15, L16 13⁄4 turns enamelled 2 mm copper wire 40 nH int. dia. 10 mm leads 2 × 7 mm space 1 mm L18, L19 stripline; note 2 43 Ω length 13 mm width 6 mm L20, L21 stripline; note 2 43 Ω length 29.5 mm width 6 mm R1 metal film resistor 10 Ω, 0.4 W R2, R7 10 turns potentiometer 50 kΩ R3, R6 metal film resistor 1 kΩ, 0.4 W R4, R5 metal film resistor 2 × 5.62 Ω, in parallel, 0.4 W R8, R9 metal film resistor 10 Ω ±5%, 1 W R10 metal film resistor 4 × 42.2 Ω in parallel, 1 W R11 metal film resistor 5.11 kΩ, 1 W IC1 voltage regulator 78L05 CATALOGUE NO. 4312 020 36642 Notes 1. American Technical Ceramics capacitor, type 100B or other capacitor of the same quality. 2. L1, L3 to L13, L18 to L22 and L24 are microstriplines on a double copper-clad printed-circuit board, with fibre-glass reinforced PTFE dielectric (εr = 2.2), thickness 1⁄16 inch; thickness of copper sheet 2 × 35 µm. 3. L2 and L23 are soldered on to striplines L1 and L24 respectively. 1996 Oct 21 17 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 130 119 handbook, full pagewidth strap strap strap strap Hollow rivets Hollow rivets 100 strap strap strap strap C24 VDD1 R11 C38 L2 C35 slider R2 L1 C1 50 Ω input to R2,R7 C36 C16 IC1 C3 R1 C2 C37 C11 C13 R6 L3 C8 C10 R3 R4 L4 C6 L6 L8 L10 C5 C7 L7 L9 L11 L5 C4 slider R7 C15 L15 L12 C20 L13 R5 C12 C18 C17 C23 L22 VDD1 C30 C31C33 L18 C28 L20 C21 C29 L19 L21 C34 C32 L16 C9 C22 C14 L14 R8 L14 R10 50 Ω output VDD2 L17 R9 L17 C19 C25 L23 L24 C26 C27 MBC436 Dimensions in mm. The circuit and components are situated on one side of the PTFE fibre-glass board, the other side being fully metallized to serve as an earth. Earth connections are made by means of copper straps for a direct contact between upper and lower sheets. Fig.22 Printed-circuit board and component layout for 225 MHz class-AB test circuit. 1996 Oct 21 18 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 MGE611 2 MGE625 3 handbook, halfpage handbook, halfpage zi (Ω) ZL (Ω) 1 ri XL 2 0 1 xi RL −1 –2 150 200 f (MHz) 0 150 250 200 f (MHz) 250 Class-AB operation; VDS = 50 V; IDQ = 2 × 0.5 A; RGS = 2.8 Ω (per section); PL = 250 W. Class-AB operation; VDS = 50 V; IDQ = 2 × 0.5 A; RGS = 2.8 Ω (per section); PL = 250 W. Fig.23 Input impedance as a function of frequency (series components), typical values per section. Fig.24 Load impedance as a function of frequency (series components), typical values per section. MGE624 20 handbook, halfpage Gp (dB) handbook, halfpage 10 Zi ZL MBA379 0 150 200 f (MHz) 250 Class-AB operation; VDS = 50 V; IDQ = 2 × 0.5 A; RGS = 2.8 Ω (per section); PL = 250 W. Fig.26 Power gain as a function of frequency, typical values per section. Fig.25 Definition of MOS impedance. 1996 Oct 21 19 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 PACKAGE OUTLINE 0.25 11 max 11 max 0.13 2.92 2.29 1.65 5.8 max 1.02 seating plane 21.85 0.25 M 5.9 5.5 (4x) 2.54 1 2 10.4 max 3.3 9.8 15.6 3.0 max 5 3 4 5.525 11.05 27.94 34.3 max Dimensions in mm. Fig.27 SOT262A1. 1996 Oct 21 20 MSA285 - 2 Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 DEFINITIONS Data Sheet Status Objective specification This data sheet contains target or goal specifications for product development. Preliminary specification This data sheet contains preliminary data; supplementary data may be published later. Product specification This data sheet contains final product specifications. Limiting values Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability. Application information Where application information is given, it is advisory and does not form part of the specification. LIFE SUPPORT APPLICATIONS These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be expected to result in personal injury. Philips customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Philips for any damages resulting from such improper use or sale. 1996 Oct 21 21