PIP202-12M DC to DC converter powertrain Rev. 01 — 15 July 2002 Product data M3D797 1. Description The PIP202-12M is designed for use as the power output stage of a synchronous buck DC to DC converter. It contains a MOSFET control IC, two power MOSFET transistors and a Schottky diode. By combining the power MOSFETs and the driver circuit into a single component, stray inductances are virtually eliminated, resulting in higher switching frequency, lower switching losses and a compact, efficient design. 2. Features ■ ■ ■ ■ ■ ■ ■ ■ Input voltage conversion range from 3.3 V to 12 V Output voltages from 0.8 V to 5 V Capable of up to 25 A continuous output current Operating frequency up to 1 MHz Peak system efficiency >92% at 500 kHz High efficiency Low-profile, surface mount package (10 × 10 × 0.85 mm) Compatible with any single or multi-phase PWM controller. 3. Applications ■ High-current DC to DC point-of-load converters ■ Small form-factor Voltage Regulator Modules ■ Microprocessor and memory voltage regulators. 4. Ordering information Table 1: Ordering information Type number PIP202-12M Package Name Description HVQFN68 (MLF68) plastic, thermal enhanced very thin quad flat package; no leads; SOT687-1 68 terminals; body 10 × 10 × 0.85 mm Version PIP202-12M Philips Semiconductors DC to DC converter powertrain 5. Block diagram VDDC control cct supply 1 to 8, 60, 61 68, PAD1 11, 12 13, 14 PIP202-12M VDDO CB bootstrap capacitor driveH VI VSSC n.c. pwm input 16, 17 10, 26, 27, 45 to 59 62 to 67, PAD3 sourceH 9, 15 22 to 24, PAD2 control cct gnd 18 to 21, 25 VO driveL 28 to 44 sourceL VSSO 03ag51 A bootstrap diode is integrated into the design of the PIP202-12M between VDDC and CB. Fig 1. Block diagram. 6. Pinning information 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 VDDO VO VO VO VO VO VO VDDO VDDO VO VO VO VO VO VO VO VO 6.1 Pinning 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 VDDO PAD 1 VO PAD 3 VSSC PAD 2 PIP202-12M 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 VO VO VO VO VO VO VO VSSO VSSO V SSO VSSO VSSO VSSO VSSO VSSO VSSO VSSO VSSC VSSC VSSC n.c. VO VO VSSO VSSO VSSO VSSO VSSO VSSO VSSO n.c. n.c. n.c. n.c. 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 VDDO VDDO VDDO VDDO VDDO VDDO VDDO VDDO VSSC VO CB CB VDDC VDDC VSSC VI VI 03ag52 Grey area denotes terminal 1 index area. Fig 2. Pin configuration (footprint view). © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 2 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 6.2 Pin description Table 2: Pin description Symbol Pin VDDO 1 to 8, 60, 61, 68 [1] [4] 9, 15, 22 to 24 VO 10, 26, 27, 45 to 59, 62 to 67 CB VDDC VSSC I/O Description - output stage supply voltage [2] [4] - control circuit supply ground [3] [4] O output 11, 12 I/O bootstrap capacitor connection 13, 14 - control circuit supply voltage VI 16, 17 I pulse width modulated input VSSO 28 to 44 − output stage supply ground n.c. 18 to 21, 25 − no internal connection [1] [2] [3] [4] [5] [5] All pins connected to PAD1 All pins connected to PAD2 All pins connected to PAD3 PAD1, PAD2 and PAD3 are electrical connections and must be soldered to the printed circuit board All n.c. pins should be connected to VSSC. 7. Functional description 7.1 Basic functionality output stage supply voltage control circuit supply (12 V) VDDC CB input voltage VI from PWM controller VI VSSC tp T δ= tp T 100 nF VDDO Lout VO output Cout VSSO signal ground power ground 03ad36 Fig 3. Simplified functional block diagram of a synchronous DC to DC converter output stage. In order to understand the functions performed by the PIP202-12M, consider the requirements of a synchronous DC to DC converter output stage, driven from a PWM controller (Figure 3). When the input voltage is HIGH, the upper MOSFET must be on and the lower MOSFET must be off. Current flows from the supply (VDDO), through the upper MOSFET and the inductor (Lout), to the output. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 3 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain When the input voltage is LOW and current is flowing in the inductor, the upper MOSFET must be off and the lower MOSFET must be on. Current flows from the power ground (VSSO), through the lower MOSFET and the inductor (Lout), to the output. Finally, when switching between states, both MOSFETs must not be on at the same time. 7.2 MOSFET driver function input voltage upper MOSFET gate drive delay lower MOSFET gate drive delay output voltage 03ag35 Fig 4. Input, output and gate drive waveforms of a synchronous DC to DC converter output stage. The input, output and gate drive waveforms are shown in Figure 4. When the input voltage goes HIGH, the gate drive to the lower MOSFET immediately goes LOW. This causes the output current to flow through the Schottky diode, connected between the drain and source of the lower MOSFET. This causes output voltage to fall from zero to approximately −0.5 V. After a delay, if the input voltage is still HIGH, the gate drive to the upper MOSFET goes HIGH. This causes the output voltage to rise to the output stage supply voltage, VDDO. When the input voltage goes LOW, the gate drive to the upper MOSFET immediately goes LOW. The output voltage falls from VDDO, until it is clamped by the Schottky diode at approximately −0.5 V. After a delay, if the input voltage is still LOW, the gate drive to the lower MOSFET goes HIGH. The lower MOSFET turns on, and the output voltage rises from −0.5 V to zero. 7.3 Bootstrap diode A bootstrap diode is integrated into the design of the PIP202-12M between VDDC and CB. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 4 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 7.4 3-state function If the input from the PWM controller becomes high impedance (3-state) for longer than144 ns, then both MOSFETs are turned off and the VI input is driven to 2.5 V by an internal 2 x 10 kΩ resistor voltage divider between an internal 5 V reference and ground. 8. Limiting values Table 3: Limiting values In accordance with the Absolute Maximum Rating System (IEC 60134). Symbol Parameter VDDC Conditions Min Max Unit control circuit supply voltage −0.5 14 V VDDO output stage supply voltage −0.5 25 V VI input voltage −0.5 5.25 V VO output voltage −0.5 VDDO + 0.5 V VCB bootstrap voltage −0.5 VO + 14 V IO(AV) average output current VDDC = 12 V; Tpcb ≤ 110 °C; Figure 5 A IORM repetitive peak output current Ptot total power dissipation - 25 VDDC = 12 V; tp ≤ 10 µs [1] - 200 A Tpcb = 25 °C [2] - 25 W Tpcb = 90 °C [2] - 12 W Tstg storage temperature −55 +150 °C Tj junction temperature −55 +150 °C [1] [2] Pulse width and repetition rate limited by maximum value of Tj. Assumes a thermal resistance from junction to printed-circuit board of 5 K/W. 03ag41 30 IO(AV) (A) 20 10 0 0 50 100 150 Tpcb (°C) VDDC = 12 V; VDDO = 12 V; fi = 500 kHz; VO = 1.6 V. Fig 5. Average output current as a function of printed-circuit board temperature. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 5 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 9. Thermal characteristics Table 4: Thermal characteristics Symbol Parameter Rth(j-pcb) thermal resistance from junction to printed-circuit board Rth(j-a) thermal resistance from junction to ambient Rth(j-c) thermal resistance from junction to case Conditions Min Typ Max Unit - 4 5 K/W no thermal vias - 25 - K/W with thermal vias - 20 - K/W with thermal vias and forced air cooling; airflow = 0.8 ms-1 (150 LFM) - 15 - K/W - 11 - K/W Min Typ Max Unit device mounted on FR4 printed-circuit board; copper area around device 25 × 25 mm measured on upper surface of package. 10. Characteristics Table 5: Characteristics VDDC = 12 V; Tj = 25 °C unless otherwise specified. Symbol Parameter Conditions Static characteristics control circuit supply voltage 25 °C ≤ Tj ≤ 150 °C HIGH-level input voltage VIL 7 12 14 V 25 °C ≤ Tj ≤ 150 °C [1] 2.55 2.8 3.05 V LOW-level input voltage 25 °C ≤ Tj ≤ 150 °C [1] 1.95 2.1 2.25 V ILI input leakage current 0 V ≤ VI ≤ 5 V - 0.3 1.2 mA IDDC control circuit supply current fi = 0 Hz - 1.5 3 mA fi = 500 kHz; Figure 10 - 45 60 mA VDDO = 12 V; IO(AV) = 20 A; fi = 500 kHz; VO = 1.6 V; Tpcb ≤ 120 °C; Figure 6 - 4.5 5.7 W td(on)(IH-OH) turn-on delay time input HIGH VDDO = 12 V; IO(AV) = 25 A to output HIGH - 77 85 ns td(off)(IL-OL) turn-off delay time input LOW to output LOW - 30 45 ns to(r) output rise time - 18 25 ns to(f) output fall time - 12 20 ns td(3-state) 3-state enable delay time 115 144 173 ns VDDC VIH total power dissipation Ptot Dynamic characteristics [1] If the input voltage remains between VIH and VIL (2.5 V typ) for longer than td(3-state), then both MOSFETs are turned off. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 6 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 03ag53 8 03ag54 1.6 Ptot (W) a 6 (1) 1.4 (2) 4 1.2 2 1 0 0.8 0 5 10 15 20 25 IO(AV) (A) 5 10 15 VDDO (V) 20 VDDC = 12 V; VDDO = 12 V; VO = 1.6 V; fi = 500 kHz VDDC = 12 V; VO = 1.6 V; fi = 500 kHz; IO(AV) = 12.5 A (1) maximum P tot a = --------------------------------------P tot ( V = 12V ) (2) typical DDO Fig 6. Total power dissipation as a function of average output current; maximum and typical values. 03ag74 03ag55 1.3 Fig 7. Normalized power dissipation as a function of output stage supply voltage; typical values. 1.6 c b 1.4 1.2 1.2 1.1 1 1 0.8 0.9 0.6 1 2 3 4 VO (V) 5 200 VDDC = 12 V; VDDO = 12 V; fi = 500 kHz; IO(AV) = 12.5 A 600 800 1000 fi (kHz) VDDC = 12 V; VDDO = 12 V; VO = 1.6 V; IO(AV) = 12.5 A P tot b = ---------------------------------P tot ( V = 1.6V ) P tot c = -------------------------------------P tot ( f = 500kHz ) O i Fig 8. Normalized power dissipation as a function of output voltage; typical values. Fig 9. Normalized power dissipation as a function of input frequency; typical values. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data 400 Rev. 01 — 15 July 2002 7 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 03ae75 100 IDDC (mA) 80 60 40 20 0 250 500 750 fi (kHz) 1000 VDDC = 12 V; VDDO = 12 V; VO = 1.6 V; IO(AV) = 12.5 A. Fig 10. Control circuit supply current as a function of input frequency; typical values. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 8 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 11. Application information 11.1 Typical application 10 Ω control circuit supply (12 V) conversion supply (12 V) 1 µF 100 nF 22 µF (4x) VDDC CB VDDO 360 nH VI VO PIP202-12M VSSC VSSO 100 µF (2x) 2.2 nF 2.2 Ω 10 Ω 22 µF (4x) 1 µF 100 nF VDDC CB VDDO 360 nH VI VO PIP202-12M PWM 1 PWM 2 PWM Controller 2.2 nF 100 µF (2x) 2.2 Ω 10 Ω PWM 3 PWM 4 VSSO VSSC 1 µF 100 nF 22 µF (4x) VDDC CB VDDO 360 nH VI VO PIP202-12M VSSC VSSO 2.2 nF 100 µF (2x) 2.2 Ω 10 Ω 1 µF 22 µF (4x) 100 nF VDDC CB VDDO output voltage 360 nH VI signal ground power ground VO PIP202-12M VSSC VSSO 2.2 nF 100 µF (2x) 2.2 Ω 03ag56 Fig 11. Typical application circuit using the PIP202-12M in a four-phase converter. A typical four-phase buck converter is shown in Figure 11. This system uses four PIP202-12M devices to deliver a continuous output current of 80 A at an operating frequency of 500 kHz. Remark: An external bootstrap diode is not required as one is already integrated into the design of the PIP202-12M between VDDC and CB. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 9 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain At 500 KHz and 20 A output current, the maximum dissipation in each PIP202-12M is 5.7 W. The typical thermal resistance from junction to ambient is given in Table 4. With thermal vias and forced air cooling, the thermal resistance of each PIP202-12M from junction to ambient is15 K/W. Assuming a maximum ambient temperature of 55 °C, the maximum junction temperature (Tj(max)) is given by: T j ( max ) = P tot × R th ( j – a ) + T amb = 5.7 × 15 + 55 = 140.5°C (1) The thermal resistance between the junction and the printed-circuit board is 5 K/W. Therefore, the maximum printed-circuit board temperature (Tpcb(max)) is given by: T pcb ( max ) = T j ( max ) – P tot × R th ( j – pcb ) = 140.5 – 5.7 × 5 = 112°C (2) 11.2 Advantages of an integrated driver One problem in the design of low-voltage, high-current DC to DC converters using discrete components, is stray inductance between the various circuit elements. Stray inductance in the gate drive circuit increases the switching times of the MOSFETs and causes high-frequency oscillation of the gate voltage. Stray inductance in the high-current loop between VDDO and VSSO causes switching losses and electromagnetic interference. In discrete designs, high-frequency electric and magnetic fields radiate from PCB tracks and couple into adjacent circuits. By integrating the power MOSFETs and their drive circuits into a single package, stray inductance is virtually eliminated, resulting in a compact, efficient design. In discrete designs, the delays in the MOSFET drivers must be long enough to ensure no cross-conduction even when using the slowest MOSFETs. Use of an integrated driver allows the propagation delays in the MOSFET drivers to be precisely matched to the MOSFETs. This minimizes switching losses and eliminates cross-conduction whilst allowing the circuit to operate at a higher frequency. 11.3 External connection of power and signal lines A major benefit of the PIP202-12M module is the ability to switch the internal power MOSFETs faster than a DC to DC converter built from discrete components. This not only reduces switching losses and increases system efficiency but it also results in higher transient voltages on the device supply lines (VDDO and VSSO). This is due to the high rate of change of current (dI/dt) through the combined parasitic inductance of the PCB tracks and the decoupling capacitors. To minimize the amplitude of these transients, decoupling capacitors must be placed between VDDO and VSSO, as close as possible to the device pins. Low inductance, chip ceramic capacitors are recommended. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 10 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain output stage supply voltage 10 Ω control circuit supply (12 V) 1 µF input voltage from PWM controller 100 nF VDDC CB VDDO Lout VO VI VSSC VSSO output Cin Cout signal ground power ground 03ae27 Fig 12. External connection of power and signal lines. To protect the control circuit from the transient voltages, the following precautions must be taken. Refer to Figure 12. 1. The output stage ground (VSSO) must be connected to the decoupling capacitor (Cin) before joining the ground plane. Otherwise, the switching noise on VSSO will couple into the control circuit ground (VSSC). 2. The control circuit supply must be filtered using a resistor-capacitor (RC) filter. The values shown in Figure 12 are suitable for most applications. 3. It is essential that the VSSC (signal ground) connection at the device is not connected in the current return path between the VSSO (power ground) connection at the device and the VDDO input capacitor. 4. It is also essential that the input to the VDDC (logic power) filter is not connected in the current path between the VDDO (conversion power) connection at the device. 11.4 Switching frequency A high operating frequency reduces the size and number of capacitors needed to filter the output current, and also reduces the size of the output inductors. The disadvantage, however is higher dissipation due to switching and MOSFET driver losses. For example, doubling the operating frequency of the circuit in Figure 11 from 500 kHz to 1 MHz would increase the power dissipation in each PIP202-12M from 4 W to 6 W, at an output current of 20 A in each PIP202-12M. The maximum switching frequency is limited by thermal considerations, the dissipation in the PIP202-12M device(s) and the thermal resistance from junction to ambient. 11.5 Thermal design The PIP202-12M has three pads on its underside. These are designated PAD1, PAD2 and PAD3 (Figure 2). PAD1 is connected to VDDO, PAD2 is connected to VSSC and PAD3 is connected to VO. In addition to providing low inductance electrical connections, these pads conduct heat away efficiently from the MOSFETs and control IC to the printed-circuit board. The thermal resistance from junction to printed-circuit board is approximately 5 K/W. In order to take full advantage of the low © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 11 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain thermal resistance of this package, the printed-circuit board must be designed so that heat is conducted away efficiently from the package. This can be achieved by maximizing the area of copper around each pad, and by incorporating thermal vias to conduct the heat to inner and/or bottom layers of the printed-circuit board. An example of a thermal via pattern is shown in Figure 13. In a typical application, with no forced air cooling, the use of thermal vias typically reduces the thermal resistance from 25 K/W to 20 K/W. The additional use of a small fan can reduce this further to approximately 15 K/W. PAD1 PAD3 PAD2 03ag36 All holes 0.5 mm diameter with 1 mm spacing. Fig 13. Printed-circuit board thermal via pattern. The thermal resistance of a particular design can be measured by passing a known current between VSSO and VDDO. The current flows through the Schottky diode and through the source-drain diode of the upper MOSFET. The direction of current flow is into VSSO and out of VDDO. The volt drop between VSSO and VDDO is then measured and used to calculate the power dissipation in the PIP202-12M. The case temperature of the PIP202-12M can be measured using an infra-red thermometer. The thermal resistance can then be calculated using the following equation: T case – T amb R th ( j – pcb ) = ------------------------------- ( K ⁄ W ) I × VF (3) where Tcase is the measured case temperature (°C), Tamb is the ambient temperature (°C), I is the MOSFET current (A), and VF is the voltage drop between VSSO and VDDO (V). Where more than one phase is used, for example the circuit of Figure 11, the thermal resistance of each PIP202-12M should be measured with current flowing in all phases. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 12 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 12. Test information Figure 14 shows the test circuit used to measure power loss in the PIP202-12M. The output voltage is measured using an averaging circuit. This eliminates losses in the output inductor and the PCB tracks. The calculated power loss, using this method, includes the losses in the Equivalent Series Resistance (ESR) of the input filter capacitors. This must be subtracted from the total loss to give the net loss in the PIP202-12M. IDDO output stage supply control circuit supply (12 V) A IDDC V VDDO A 100 nF VDDC CB VDDO IO 500 nH VO VI input voltage from pulse generator A VSSC VSSO load VI signal ground power ground averaging circuit VO(AV) V 03ai73 P DDO = V DDO × I DDO P DDC = V DDC × I DDC P O = V O ( AV ) × I O P tot = P DDO + P DDC – P O Fig 14. Power loss (Ptot) test circuit. 13. Marking terminal 1 index area TYPE No. Design centre k = Hazel Grove, UK Release status code X = Development Sample Y = Customer Qualification Sample blank = Released for Supply DIFFUSION LOT No. Diffusion centre h = Hazel Grove, UK MANUFACTURING CODE hfkYYWWY COUNTRY OF ORIGIN Assembly centre f = Anam Korea Date code YY = last two digits of year WW = week number 03ag38 03ai72 TYPE No: PIP202-12M-NN (NN is version number) DIFFUSION LOT No: 7 characters MANUFACTURING CODE: see Figure 16 COUNTRY OF ORIGIN: Korea Fig 15. SOT687-1 marking. Fig 16. Interpretation of manufacturing code. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 13 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 14. Package outline HVQFN68: plastic thermal enhanced very thin quad flat package; no leads; 68 terminals; body 10 x 10 x 0.85 mm SOT687-1 B D A D1 A A4 A1 c E1 E detail X terminal 1 index area C e1 terminal 1 index area e 17 y y1 C v M C A B w M C b 1 L 18 68 e Eh1 e2 Eh1 34 52 51 35 Dh1 Dh1 X Dh 0 2.5 5 mm scale DIMENSIONS (mm are the original dimensions) UNIT A max. A1 A4 b c mm 1 0.05 0.00 0.80 0.65 0.30 0.18 0.2 D D1 10.15 9.95 9.85 9.55 Dh Dh1 7.85 7.55 3.8 3.5 E E1 10.15 9.95 9.85 9.55 Eh1 e e1 e2 L v w y y1 3.8 3.5 0.5 8 8 0.75 0.50 0.1 0.05 0.05 0.1 REFERENCES OUTLINE VERSION IEC JEDEC JEITA SOT687-1 --- MO-220 --- EUROPEAN PROJECTION ISSUE DATE 01-12-04 02-04-24 Fig 17. SOT687-1. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 14 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 15. Soldering 15.1 Introduction to soldering MLF packages The MicroLeadFrame package (MLF) is a near Chip Scale Package (CSP) with a copper leadframe. It is a leadless package, where electrical contact to the printed circuit board is made through metal pads on the underside of the package. In addition to the small pads around the periphery of the package, there are large pads on the underside that provide low thermal resistance, low electrical resistance, low inductance connections between the power components inside the MLF package and the PCB. It is this feature of the MLF package that makes it ideally suited for VRM applications. Electrical connection between the package and the printed circuit board is made by printing solder paste on the printed circuit board, placing the component and reflowing the solder in a convection or infra-red oven. The solder reflow process is shown in Figure 18 and the typical temperature profile is shown in Figure 19. To ensure good solder joints, the peak temperature Tp should not exceed 220° C for thin packages such as MLF, and the time above liquidus temperature should be less than 1.25 minutes. The maximum temperature can be increased for lead free solder. The ramp rate during preheat should not exceed 3 K/s. Nitrogen purge is recommended during reflow. SOLDER PASTE PRINTING POST PRINT INSPECTION 03aj26 300 Temp (°C) COMPONENT PLACEMENT Tp 200 Tr PRE REFLOW INSPECTION 1 min max REFLOW SOLDERING 100 rate of rise of temperature < 3 K/s POST REFLOW INSPECTION (PREFERABLY X-RAY) REWORK AND TOUCH UP 0 0 03aj25 Fig 18. Typical reflow soldering process flow. 1 2 time (minutes) 3 Fig 19. Typical reflow soldering temperature profile. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data 1.25 min max Te Rev. 01 — 15 July 2002 15 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 15.2 Rework guidelines Since the solder joints are largely inaccessible, only the side fillets can be touched up. If there are defects underneath the package, then the whole package has to be removed. The first step in component removal is to reflow the solder joints. It is recommended that the board is heated from the underside using a convective heater whilst hot air or gas is directed at the upper surface of the component. Nozzles should be used to direct the hot air or gas to minimize heating of adjacent components. Excessive airflow should be avoided since this may cause the package to skew. An airflow of 15 to 20 liters per minute is usually adequate. Once the solder joints have reflowed, the component should be lifted off the board using a vacuum pen. The next step is to clean the solder pads using solder braid and a blade shaped soldering tool. Finally, the pads should be cleaned with a solvent. The solvent is usually specific to the type of solder paste used in the original assembly and the paste manufacturers recommendations should be followed. 16. Mounting 16.1 PCB design guidelines The terminals on the underside of the package are rectangular in shape with a rounded edge on the inside. Electrical connection between the package and the printed-circuit board is made by printing solder paste onto the PCB footprint followed by component placement and reflow soldering. The PCB footprint shown in Figure 20 is designed to form reliable solder joints. The use of solder resist between each solder land is recommended. PCB tracks should not be routed through the corner areas shown in Figure 20. This is because there is a small, exposed remnant of the leadframe in each corner of the package, left over from the cropping process. Good surface flatness of the PCB lands is desirable to ensure accuracy of placement after soldering. Printed-circuit boards that are finished with a roller tin process tend to leave small lumps of tin in the corners of each land. Levelling with a hot air knife improves flatness. Alternatively, an electro-less silver or silver immersion process produces completely flat PCB lands. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 16 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 11.15 OA (2×) handbook, full pagewidth 7.6 Cu (2×) e = 0.5 4.1 0.4 SP (2×) 0.6 Cu 1 SP (8×) 1 SP (8×) 0.4 SP 8.63 OA (4×) 4.1 0.6 Cu 0.4 SP 1 SP (10×) 0.28 Cu (68×) 0.5 SP (4×) solder lands 0.9 SP (10×) 8.9 Cu (2×) 0.1 Cu pattern 10.8 Cu (2×) MGW820 0.2 clearance 0.025 solder paste occupied area All dimensions in mm. Fig 20. PCB footprint for SOT687-1 package (reflow soldering). 16.2 Solder paste printing The process of printing the solder paste requires care because of the fine pitch and small size of the solder lands. A stencil thickness of 0.125 mm is recommended. The stencil apertures can be made the same size as the PCB lands in Figure 20. The type of solder paste recommended for MLF packages is "No clean", Type 3, due to the difficulty of cleaning flux residues from beneath the MLF package. © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 17 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 17. Revision history Table 6: Revision history Rev Date 01 20020715 CPCN Description - Product data (9397 750 10031) © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Product data Rev. 01 — 15 July 2002 18 of 20 PIP202-12M Philips Semiconductors DC to DC converter powertrain 18. Data sheet status Data sheet status[1] Product status[2] Definition Objective data Development This data sheet contains data from the objective specification for product development. Philips Semiconductors reserves the right to change the specification in any manner without notice. Preliminary data Qualification This data sheet contains data from the preliminary specification. Supplementary data will be published at a later date. Philips Semiconductors reserves the right to change the specification without notice, in order to improve the design and supply the best possible product. Product data Production This data sheet contains data from the product specification. Philips Semiconductors reserves the right to make changes at any time in order to improve the design, manufacturing and supply. Changes will be communicated according to the Customer Product/Process Change Notification (CPCN) procedure SNW-SQ-650A. [1] Please consult the most recently issued data sheet before initiating or completing a design. [2] The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet at URL http://www.semiconductors.philips.com. 19. Definitions 20. Disclaimers Short-form specification — The data in a short-form specification is extracted from a full data sheet with the same type number and title. For detailed information see the relevant data sheet or data handbook. Life support — 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 Semiconductors customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application. Limiting values definition — Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 60134). 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 — Applications that are described herein for any of these products are for illustrative purposes only. Philips Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or modification. Right to make changes — Philips Semiconductors reserves the right to make changes, without notice, in the products, including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no licence or title under any patent, copyright, or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless otherwise specified. Contact information For additional information, please visit http://www.semiconductors.philips.com. For sales office addresses, send e-mail to: [email protected]. Product data Fax: +31 40 27 24825 © Koninklijke Philips Electronics N.V. 2002. All rights reserved. 9397 750 10031 Rev. 01 — 15 July 2002 19 of 20 Philips Semiconductors PIP202-12M DC to DC converter powertrain Contents 1 2 3 4 5 6 6.1 6.2 7 7.1 7.2 7.3 7.4 8 9 10 11 11.1 11.2 11.3 11.4 11.5 12 13 14 15 15.1 15.2 16 16.1 16.2 17 18 19 20 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Ordering information . . . . . . . . . . . . . . . . . . . . . 1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Pinning information . . . . . . . . . . . . . . . . . . . . . . 2 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 3 Functional description . . . . . . . . . . . . . . . . . . . 3 Basic functionality . . . . . . . . . . . . . . . . . . . . . . . 3 MOSFET driver function . . . . . . . . . . . . . . . . . . 4 Bootstrap diode. . . . . . . . . . . . . . . . . . . . . . . . . 4 3-state function . . . . . . . . . . . . . . . . . . . . . . . . . 5 Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . . 5 Thermal characteristics. . . . . . . . . . . . . . . . . . . 6 Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Application information. . . . . . . . . . . . . . . . . . . 9 Typical application. . . . . . . . . . . . . . . . . . . . . . . 9 Advantages of an integrated driver . . . . . . . . . 10 External connection of power and signal lines 10 Switching frequency . . . . . . . . . . . . . . . . . . . . 11 Thermal design. . . . . . . . . . . . . . . . . . . . . . . . 11 Test information . . . . . . . . . . . . . . . . . . . . . . . . 13 Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Package outline . . . . . . . . . . . . . . . . . . . . . . . . 14 Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Introduction to soldering MLF packages. . . . . 15 Rework guidelines . . . . . . . . . . . . . . . . . . . . . 16 Mounting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 PCB design guidelines . . . . . . . . . . . . . . . . . . 16 Solder paste printing. . . . . . . . . . . . . . . . . . . . 17 Revision history . . . . . . . . . . . . . . . . . . . . . . . . 18 Data sheet status . . . . . . . . . . . . . . . . . . . . . . . 19 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 © Koninklijke Philips Electronics N.V. 2002. Printed in The Netherlands All rights are reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license under patent- or other industrial or intellectual property rights. Date of release: 15 July 2002 Document order number: 9397 750 10031