BLF278_15 JMNIC | Alldatasheet
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Technical content
Product Specification Supersedes data of October 1992
1996 Oct 21
1996 Oct 21 2
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278
FEATURES
- High power gain
- Easy power control
- Good thermal stability
- Gold metallization ensures excellent reliability.
APPLICATIONS
- Broadcast transmitters in the VHF frequency range.
DESCRIPTION
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. CAUTION The device is supplied in an antistatic package. The gate-source input must be protected against static discharge during transport or handling. PINNING - SOT262A1 PIN SYMBOL DESCRIPTION 1d 1 drain 1 2d 2 drain 2 3g 1 gate 1 4g 2 gate 2 5 s source Fig.1 Simplified outline and symbol. MAM098Top view d g s d g QUICK REFERENCE DATA RF performance at Th =2 5°C in a push-pull common source test circuit. MODE OF OPERATION f (MHz) VDS (V) PL (W) G p (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 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 3
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 LIMITING VALUES In accordance with the Absolute Maximum System (IEC 134). THERMAL CHARACTERISTICS 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) − 18 A Ptot total power dissipation up to T mb =2 5°C total device; both sections equally loaded − 500 W Tstg storage temperature −65 150 °C Tj junction temperature − 200 °C SYMBOL PARAMETER CONDITIONS VALUE UNIT R th j-mb thermal resistance from junction to mounting base total device; both sections equally loaded. max. 0.35 K/W R th mb-h thermal resistance from mounting base to heatsink total device; both sections equally loaded. max. 0.15 K/W Fig.2 DC SOAR. Total device; both sections equally loaded. (1) Current is this area may be limited by RDSon . (2) Tmb =2 5°C. handbook, halfpage 100 1 10 100 (1) 500 ID (A) V (V)DS MRA988 (2) Fig.3 Power derating curves. Total device; both sections equally loaded. (1) Continuous operation. (2) Short-time operation during mismatch. handbook, halfpage 0 40 80 160 500 400 MGE616 120 300 200 100 Ptot (W) Th (°C) (2) (1)
1996 Oct 21 4
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 CHARACTERISTICS Tj=2 5°C unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT Per transistor section V(BR)DSS drain-source breakdown voltage VGS = 0; ID =5 0m A 1 1 0 −− V IDSS drain-source leakage current VGS = 0; VDS =5 0V −− 2.5 mA IGSS gate-source leakage current VGS = ±20 V; VDS =0 −− 1 µA VGSth gate-source threshold voltage VDS =1 0V ; ID =5 0m A 2 − 4.5 V ΔVGS gate-source voltage difference of both sections VDS =1 0V ; ID =5 0m A −− 100 mV gfs forward transconductance V DS =1 0V ; ID = 5 A 4.5 6.2 − S gfs1/gfs2 forward transconductance ratio of both sections VDS =1 0V ; ID =5A 0 . 9 − 1.1 R DSon drain-source on-state resistance VGS = 10 V; ID =5A − 0.2 0.3 Ω IDSX drain cut-off current V GS = 10 V; VDS =1 0V − 25 − A C is input capacitance V GS = 0; VDS = 50 V; f = 1 MHz− 480 − pF C os output capacitance V GS = 0; VDS = 50 V; f = 1 MHz− 190 − pF C rs feedback capacitance V GS = 0; VDS = 50 V; f = 1 MHz− 14 − pF C d-f drain-flange capacitance − 5.4 − pF Fig.4 Temperature coefficient of gate-source voltage as a function of drain current; typical values per section. VDS =1 0V . handbook, halfpage0 10−2 10−1 MGE623 11 0 T.C. (mV/K) ID (A) Fig.5 Drain current as a function of gate-source voltage; typical values per section. VDS = 10 V; Tj=2 5°C. handbook, halfpage ID (A) VGS (V) MGE622
1996 Oct 21 5
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Fig.6 Drain-source on-state resistance as a function of junction temperature; typical values per section. VGS = 10 V; ID =5A . handbook, halfpage 0 50 100 150 400 200 100 300 MGE621 R DSon (mΩ ) Tj (°C) Fig.7 Input and output capacitance as functions of drain-source voltage; typical values per section. VGS = 0; f = 1 MHz. handbook, halfpage 1200 800 400 C (pF) VDS (V) MGE615 C os C is Fig.8 Feedback capacitance as a function of drain-source voltage; typical values per section. VGS = 0; f = 1 MHz. handbook, halfpage 01 0 5 0 400 300 100 200 MGE620 20 30 40 C rs (pF) VDS (V)
1996 Oct 21 6
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278
APPLICATION INFORMATION
RF performance in CW operation in a common source push-pull test circuit. Th =2 5°C; Rth mb-h= 0.15 K/W unless otherwise specified. RGS =4 Ω per section; optimum load impedance per section = 3.2 + j4.3Ω (VDS = 50 V). 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. MODE OF OPERATION f (MHz) VDS (V) IDQ (A) PL (W) G p (dB) ηD (%) CW, class-B 108 50 2 × 0.1 300 >20 typ. 22 >60 typ. 70 CW, class-C 108 50 V GS = 0 300 typ. 18 typ. 80
1996 Oct 21 7
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Fig.9 Power gain as a function of load power, typical values. Class-B operation; VDS =5 0V ;IDQ =2 × 0.1 A; f = 108 MHz; ZL = 3.2 + j4.3Ω (per section); RGS =4 Ω (per section). (1) Th =2 5°C. (2) Th =7 0°C. handbook, halfpage 200 400 600 MGE682 PL (W) G p (dB) (1) (2) Fig.10 Efficiency as a function of load power, typical values. Class-B operation; VDS =5 0V ;IDQ =2 × 0.1 A; f = 108 MHz; ZL = 3.2 + j4.3Ω (per section); RGS =4 Ω (per section). (1) Th =2 5°C. (2) Th =7 0°C. handbook, halfpage 0 200 400 PL (W) 600 ηD (%) MGE683 (1) (1) (2) (2) Fig.11 Load power as a function of input power, typical values. Class-B operation; VDS =5 0V ;IDQ =2 × 0.1 A; f = 108 MHz; ZL = 3.2 + j4.3Ω (per section); RGS =4 Ω (per section). (1) Th =2 5°C. (2) Th =7 0°C. handbook, halfpage 600 400 200 51 0 1 5 MGE684 Pi (W) PL (W) (1) (2)
1996 Oct 21 8
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Fig.12 Class-B test circuit at f = 108 MHz. handbook, full pagewidth MGE688 R11 IC1 C36 C37 C11 C35 L14 L18 L20 C14 C15 C10 C6 C7 C27 C28C26 C29 C30 C33 C31 L21 L22 L23 L19L17L13 D.U.T. C32 C34 R10 L3 L5 L7 50 Ω input 50 Ω output L4 L6 L8 C8 C12 C13 C20 C16 C21 C22 L11R8 L12 C17 +VDD1 /,/,/,/, /,/,/,/, /,/,/,/, /,/,/,/, /,/, /,/, A A +VDD1 L10 C18 C19 R9 L16 C24 C25 C23 L15 +VDD2
1996 Oct 21 9
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 List of components (see Figs12 and 13). COMPONENT DESCRIPTION VALUE DIMENSIONS CATALOGUE NO. C1, C2, C33, C34 multilayer ceramic chip capacitor; note 1 22 pF, 500 V C3, C4 multilayer ceramic chip capacitor; note 1 100 pF + 68 pF in parallel, 500 V C5, C6, C28 film dielectric trimmer 5 to 60 pF 2222 809 08003 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 2222 852 47104 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 2222 809 09006 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 4312 020 36642 L12, L15 4 turns enamelled 2 mm copper wire 85 nH length 13.5 mm int. dia. 10 mm leads 2× 7m m L13, L14 stripline; note 2 43 Ω length 19.5 mm width 6 mm
1996 Oct 21 10
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 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 (ε r = 2.2), thickness1⁄16 inch; thickness of copper sheet 2× 35 µm. 3. L22 is soldered on to stripline L21. 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 k Ω R3, R6 metal film resistor 3 × 12.1Ω 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 R11 metal film resistor 5.11 k Ω, 1W IC1 voltage regulator 78L05 T1 1:1 Balun; 7 turns type 4C6 50 Ω coaxial cable wound around toroid 14 × 9 × 5 mm 4322 020 90770 COMPONENT DESCRIPTION VALUE DIMENSIONS CATALOGUE NO.
1996 Oct 21 11
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Fig.13 Printed-circuit board and component layout for 108 MHz class-B test circuit. 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. Dimensions in mm. handbook, full pagewidth 130 150 100 strap strap strap strap strap strap strap strap MBC438 R11 C36 IC1V DD1 R2 and R7 C11 C7 L5 C13R3 C12 slider R2 slider R7 C15 C10 C14 C23 C24 C25 C19 C18 V DD2 L11 L11C22 C21 C20 C16 C17 V DD1 L10 L13 L14 L17 L18 C26 C27 C28 L19 L20 C29 C30 C31 C32 C33 C34 R10 50 Ω input 50 Ω output L23 L21 L22 L12 L15 C35 L16 L16
1996 Oct 21 12
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Fig.14 Input impedance as a function of frequency (series components), typical values per section. Class-B operation; VDS = 50 V; IDQ =2 × 0.1 A; R GS =4 Ω (per section); PL = 300 W. handbook, halfpage 25 75 125 f (MHz) 175 Zi (Ω ) ri xi MGE685 Fig.15 Load impedance as a function of frequency (series components), typical values per section. Class-B operation; VDS = 50 V; IDQ =2 × 0.1 A; R GS =4 Ω (per section); PL = 300 W. handbook, halfpage 25 75 125 f (MHz) 175 ZL (Ω ) XL R L MGE686 Fig.16 Definition of MOS impedance. handbook, halfpage MBA379Zi ZL Fig.17 Power gain as a function of frequency, typical values per section. Class-B operation; VDS = 50 V; IDQ =2 × 0.1 A; R GS =4 Ω (per section); PL = 300 W. handbook, halfpage 75 125 175 MGE687 f (MHz) G p (dB)
1996 Oct 21 13
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 =2 5°C; Rth mb-h= 0.15 K/W unless otherwise specified. RGS = 2.8Ω per section; optimum load impedance per section = 0.74 + j2Ω ; (VDS = 50 V). 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. MODE OF OPERATION f (MHz) VDS (V) IDQ (A) PL (W) G p (dB) ηD (%) CW, class-AB 225 50 2 × 0.5 250 >14 typ. 16 >50 typ. 55
1996 Oct 21 14
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Fig.18 Power gain as a function of load power, typical values. Class-AB operation; VDS = 50 V; IDQ =2 × 0.5 A; f = 225 MHz; ZL = 0.74 + j2Ω (per section); RGS = 2.8Ω (per section). (1) Th =2 5°C. (2) Th =7 0°C. handbook, halfpage 0 100 200 300 MGE614 G p (dB) PL (W) (2) (1) Fig.19 Efficiency as a function of load power, typical values. Class-AB operation; VDS = 50 V; IDQ =2 × 0.5 A; f = 225 MHz; ZL = 0.74 + j2Ω (per section); RGS = 2.8Ω (per section). (1) Th =2 5°C. (2) Th =7 0°C. handbook, halfpage ηD (%) 100 200 PL (W) 300 MGE612 (2) (1) Fig.20 Load power as a function of input power, typical values. Class-AB operation; VDS = 50 V; IDQ =2 × 0.5 A; f = 225 MHz; ZL = 0.74 + j2Ω (per section); RGS = 2.8Ω (per section). (1) Th =2 5°C. (2) Th =7 0°C. handbook, halfpage 0 5 10 15 400 300 100 200 MGE613 PL (W) Pi (W) (1) (2)
1996 Oct 21 15
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Fig.21 Class-AB test circuit at f = 225 MHz. handbook, full pagewidth MGE617 L13 C17 C18 C19 R9R11 IC1 C38 C37 C36 C35 L17 C26 C27 C25 L19 L21 C12 C13 L16 C22 C14 C23 C24 L14R8 L4L1 C6 C7 C20 C21 C28 C29 C30 C33 C31 L22 L23 L24 L20L18L12 D.U.T. L15 C32 C34 R10 L6 L8 L10 L5L3 L250 Ω input 50 Ω output L7 L9 L11 C15 C10 C11 C16 +VDD1 /,/,/, /,/,/, /,/,/, /,/,/,/, /,/,/,/, /,/,/, /,/, /,/, A A +VDD1 +VDD2
1996 Oct 21 16
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 2222 809 09005 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 17
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 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 (ε r = 2.2), thickness1⁄16 inch; thickness of copper sheet 2× 35 µm. 3. L2 and L23 are soldered on to striplines L1 and L24 respectively. L14, L17 2 × grade 3B Ferroxcube wideband HF chokes in parallel 4312 020 36642 L15, L16 1 3⁄4 turns enamelled 2 mm copper wire 40 nH int. dia. 10 mm leads 2× 7m m 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 k Ω R3, R6 metal film resistor 1 k Ω , 0.4 W R4, R5 metal film resistor 2 × 5.62Ω, in parallel, 0.4 W R8, R9 metal film resistor 10 Ω± 5%, 1 W R10 metal film resistor 4 × 42.2Ω in parallel, 1 W R11 metal film resistor 5.11 k Ω, 1W IC1 voltage regulator 78L05 COMPONENT DESCRIPTION VALUE DIMENSIONS CATALOGUE NO.
1996 Oct 21 18
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Fig.22 Printed-circuit board and component layout for 225 MHz class-AB test circuit. 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. Dimensions in mm. handbook, full pagewidth MBC436 119 130 100 Hollow rivets Hollow rivets strap strap strap strap strap strap strap strap R11 C38 C35 C37 C36 C16 IC1 slider R2 slider R7 C13 R6 C12 C17 L10 L11 L8L6 L7 L9 VDD1 C10 R3 C11 C8 to R2,R7 VDD1 VDD2C9 L17 L17 C18 C25 C27 C26C19 L12 C20 L13 C21 C28L18 L19 L20 L21 C29 C31 C32 C30 C33 C34 R10 50 Ω output 50 Ω input L23 L24 L22 C14 C22 C23L14 L14 C15 C24 L15 L16
1996 Oct 21 19
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 Fig.23 Input impedance as a function of frequency (series components), typical values per section. Class-AB operation; VDS = 50 V; IDQ =2 × 0.5 A; R GS = 2.8Ω (per section); PL = 250 W. handbook, halfpage 150 200 250 MGE611 ri zi (Ω ) xi f (MHz) Fig.24 Load impedance as a function of frequency (series components), typical values per section. Class-AB operation; VDS = 50 V; IDQ =2 × 0.5 A; R GS = 2.8Ω (per section); PL = 250 W. handbook, halfpage 150 250 200 f (MHz) MGE625 XL R L ZL (Ω ) Fig.25 Definition of MOS impedance. handbook, halfpage MBA379Zi ZL Fig.26 Power gain as a function of frequency, typical values per section. Class-AB operation; VDS = 50 V; IDQ =2 × 0.5 A; R GS = 2.8Ω (per section); PL = 250 W. handbook, halfpage 150 200 250 MGE624 G p (dB) f (MHz)
1996 Oct 21 20
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 PACKAGE OUTLINE Fig.27 SOT262A1. Dimensions in mm. 3.3 3.0 9.8 15.6 max 5.525 11.05 27.94 34.3 max 2.54 10.4 max 0.25M 5.9 5.5 (4x) 21.85 seating plane 1.65 5.8 max2.92 2.29 1.02 0.13 11 max 11 max 0.25 MSA285 - 2
1996 Oct 21 21
Philips Semiconductors Product Specification VHF push-pull power MOS transistor BLF278 DEFINITIONS 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. 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. Where application information is given, it is advisory and does not form part of the specification.