Intermediate Bus Converter Demo Board Using SiP11205 or SiP11206

Transcription

1 Intermediate Bus Converter Demo Board Using SiP05 or SiP06 SiP05/06DB INTRODUCTION Both SiP05 and SiP06 are controllers for half-bridge intermediate bus converters. The difference between SiP05 and SiP06 is that SiP05 has built-in feedforward circuitry and SiP06 does not. The feed-forward circuitry adjusts duty cycle when input voltage changes. The duty cycle increases with the decrease of input voltage and the duty cycle decreases while input voltage increases. This feed-forward feature allows an IBC to be semi-regulated. While SiP06 allows better efficiency throughout the whole range of input voltage, since its duty cycle can be set to an optimized value for the whole range of input voltage. Therefore SiP05 is more suited for point of load applications that require tighter range of input voltage, which is the output of an SiP05 controlled IBC, and SiP06 is better for applications that efficiency is a key for whole input voltage range. This demo board is an eighth-brick IBC power converter, which plugs into a baseboard. The IBC board has the following specifications and options: Narrow input voltage range ( to 55 V) with SiP05 or SiP06 controller IC Wide input voltage range (6 to 75 V) with SiP05 controller IC Nominal V output, nominal load current 5 A PolarPAK SO-8 or PowerPAK SO-8 options for primary and secondary power MOSFETs The baseboard contains input fuse, input, output, and remote enable connectors, enable switch, input bulk capacitance and output voltage measurement SMC connector. The cutout in the baseboard allows for probing of both sides of the IBC board. Photos are shown in Figure. Figure. Photos of Demo Board with PolarPAK MOSFET Options This document details the following of the demo board:. Set up. Operation. Waveforms and Performance curves. Schematic and BOM 5. Board Layout S-777-Rev. A, -Oct-07

2 SiP05/06DB SET UP The connection diagram for the demo board is depicted in Figure. Power and sense connections are provided at the input and output for the main current path and for voltage sensing for efficiency monitoring. Wire rated at 5 A should be used for the input connections and x 8 A rated wire should be used for the output lines. The board can be enabled/ disabled manually by using the on-board switch S or by connecting a 0 V/5 V logic signal in the disable connector. 5 V represents Disable. Wiring lengths should be kept as short as possible, especially at the output in order to avoid excessive voltage drop across the cable length. If the input cables are less than meter long, connection of one bulk capacitor on the baseboard is sufficient. However if longer lengths are utilized, both capacitors should be connected. It should be noted that with long cable lengths, the input voltage might be quite oscillatory on power up, potentially leading to undervoltage or the converter cycling in and out of operation until the voltage becomes steady. A small fan should be placed so that cooling air is blown over the demo board in the direction shown. If the temperature of the board exceeds 05 ºC, the board will be disabled by the over temperature shutdown mechanism. Enable/disable Signal Enable/disable Switch C DISABLE D Q R R S Input Connector TP + F P D TP TP Vins+ Vin+ Vin- Vins- Vos- Vo- Vo- Vo+ Vo+ Vos+ Output Connector C SiP05/6 Demonstrator Board TP C Airflow Figure. Connection Diagram OPERATION AND TEST RESULTS The power circuit is a half-bridge converter controlled by the SiP05/6 IC. In the SiP06 version, the converter duty cycle is fixed and is set by R. It is typically set to a value close to 50 % for maximum efficiency. The output voltage is then determined by the input voltage variation and the transformer turns ratio. In this demo board, the transformer turns ratio is :. In the SiP05 version, the maximum duty cycle is set at the minimum input voltage. The duty cycle will then decrease as the input voltage increases, in a feedforward manner, resulting in a much smaller variation in output voltage over the line voltage range. The controller IC is powered at startup by its own internal 9.5 V pre-regulator, which is driven from the line voltage. Once converter switching commences, a separate 0. V V CC supply is supplied from an auxiliary transformer winding, and linear regulator R 8, Q 7, D 8. The secondary side synchronous rectifiers are self-driven, but with a controlled gate voltage that does not vary with input voltage. This results in improved efficiency and safer drive voltages. A local 0 V bias supply is generated on the secondary side through D 9, R 9, C and D 0. MOSFETs Q 8 and Q are triggered by the opposite transformer node, and the 0 V is coupled to the synchronous rectifier gate less a threshold voltage drop. In the feed-forward version, a Schottky diode is connected across the output filter. There are longer dead times in the feedforward version due to the smaller duty cycle at higher line voltages. During this dead time, the synchronous rectifiers are off as there is no transformer voltage available to turn them on. Hence, without the Schottky diode present, the inductor current will flow through the two body diodes of the synchronous rectifiers. The Schottky diode has a smaller on voltage drop than the body diodes, and so will enhance efficiency. Some typical converter waveforms are shown in Figure to 0. This demo board is laid out in such a way that Vishay Siliconix's PowerPAK and PolarPAK MOSFETs can both be used as long as they satisfy voltage and current requirements for primary and secondary. Therefore system performance may be slightly different when different MOSFETs with different footprints are used. Figure to illustrate typical system efficiency and line and load regulation curves when the PolarPAK MOSFETs SiE88DF and SiE8DF are used respectively for primary and secondary. S-777-Rev. A, -Oct-07

3 SiP05/06DB (a) V with 0.5 A load (b) V with 5 A load (c) 8 V with 0.5 A Load (d) 8 V with 5 A Load (e) 55 V with 0.5 A Load (f) 55 V with 5 A Load Figure. SiP05 Driving Signal and Inductor Voltage S-777-Rev. A, -Oct-07

4 SiP05/06DB Figure. SiP05 Startup Waveforms Figure 5. SiP05 Shutdown Waveforms Figure 6. SiP05 Hiccup Waveforms when Output is Shorted Figure 7. SiP06 Switching Waveforms S-777-Rev. A, -Oct-07

5 SiP05/06DB Figure 8. SiP06 Startup Waveforms Figure 9. SiP06 Shutdown Waveforms Efficiency 8 V Efficiency V Efficiency 55 V Figure 0. SiP06 Hiccup Waveforms when Output is Shorted Figure. SiP06 Efficiency at f SW = 5 khz Efficiency (%) Efficiency (%) Io (A) Io (A) Vin 8 Vin 55 Vin 6 Vin 8 Vin 7 Vin a) to 55 V Input Range b) 6 to 7 V Input Range Figure. SiP05 Efficiency S-777-Rev. A, -Oct-07 5

6 SiP05/06DB 8 6 Vo (V) Vo (V) Io (A) Io (A) Vin 8 Vin 55 Vin 6 Vin 8 Vin 7 Vin a) to 55 V Input Range b) 6 to 7 V Input Range Figure. SiP05 Line and Load Regulation at f SW = 5 khz 0 Vo (V) Io (A) Vin 8 Vin 55 Vin Figure. SiP06 Line and Load Regulation at f SW = 5 khz PCB LAYOUT The demo board is an 8 layer board in the eighth-brick form factor, manufactured with oz copper on the outer layers and oz copper on the inner layers. The circuit schematics for the demo board are illustrated in Figure 7 to 9. The transformer is a planar magnetic component with an E/6/6 core. The primary winding has turns, located on layers and 7, with turns per layer. Each secondary winding has turns, located on layers,, 5, and 6, with turn per layer. The auxiliary winding has turns, consisting of turns on the top layer and turn on the bottom layer. The PCB layout plots are shown in Figure to 6. 6 S-777-Rev. A, -Oct-07

7 SiP05/06DB Figure 5. Layers to of PCB (l - r) Figure 6. Layers 5 to 8 of PCB (l - r) S-777-Rev. A, -Oct-07 7

8 SiP05/06DB Figure 7. Top and Bottom PCB Component Placement (l - r) The schematics are shown in Figure 8 to 0, and parts list are shown in table and. TABLE - IBC PARTS LIST Item Ref. Description Part Number Value Footprint Manufacturer C Capacitor 00 nf, 50 V 060 C Capacitor. nf, 0 V 060 C Capacitor µf, 5 V 060 C Capacitor 00 pf, 0 V (70 khz) pf, 0 V (5 khz) C5 Capacitor nf, 0 V C6 Capacitor 0 pf, 0 V C7 Capacitor nf, 0 V C8 Capacitor C5X7RH75M.7 µf, 50 V 8 TDK 9 C0 Capacitor.7 µf, 50 V 8 TDK 0 C Capacitor C5X7RH75M 00 nf, 50 V 060 C Capacitor µf, 5 V 060 C Capacitor GRMER6C6KE0L µf, 6 V 0 Murata C5 Capacitor (Tantalum) TAJB6K06R µf, 6 V Case B AVX C7 Capacitor 00 nf, 50 V C8 Capacitor µf, 5 V D Small Signal switching diode BAV9WS-V 0. A, 00 V SOD Vishay 7 D5 SSC5 Schottky Diode 5 A, 0 V SMC Vishay 8 D7 Schottky Diode BAS70WS 70 V, 70 ma SOD Vishay 9 D8 Zener Diode BZX8B-V V, % SOD Vishay 8 S-777-Rev. A, -Oct-07

9 SiP05/06DB TABLE - IBC PARTS LIST Item Ref. Description Part Number Value Footprint Manufacturer 0 D9 Schottky Diode BAS70WS 70 V, 70 ma SOD Vishay D0 Zener Diode BZX8B-V V, % SOD Vishay J.0 mm Pin xx Mill-Max J.0 mm Pin xx Mill-Max J.0 mm Pin xx Mill-Max 5 J.58 mm Pin --00-xx Mill-Max 6 J5.58 mm Pin --00-xx Mill-Max 7 L Inductor IHLP00DZ-0 µh (. µh) b 00 Vishay 8 Q Power MOSFET Notes: a. Part values are for narrow input feed-forward version b. Part values are for wide input feed-forward version Si785DP b 80 V b PowerPAK SO8 Vishay Si78DP 60 V PowerPAK SO8 Vishay Si785DP b 80 V b PowerPAK SO8 Vishay 9 Q Power MOSFET Si78DP 60 V b PowerPAK SO8 Vishay 0 Q MOSFET Si08 60 V, A SOT Vishay Q Synch MOSFET Si756DP 0 V PowerPAK SO8 Vishay Si78DP b 60 V b PowerPAK SO8 Vishay Q5 Synch MOSFET Si756DP 0 V PowerPAK SO8 Vishay Si78DP b 60 V b PowerPAK SO8 Vishay Q6 Power MOSFET SiE88DF 75 V PolarPAK Vishay Q7 Small signal npn BJT ZXTN0F 50 V, A SOT Zetex 5 Q8 MOSFET Si08 60 V, A SOT Vishay 6 Q9 Power MOSFET SiE88DF 75 V PolarPAK Vishay 7 Q0 Synch MOSFET SiE8DF 0 V PolarPAK Vishay 8 Q Synch MOSFET SiE8DF 0 V PolarPAK Vishay 9 R Resistor 8k % R Resistor 8k, (8k) a, (80k6) b, % 060 R Resistor 0 R, % 060 R5 Resistor 6k, (6k) a, (k) b, % 060 R6 Resistor k6, % 060 R9 Resistor 00k, % R0 Resistor 00k, % R Resistor NC (75k) a, (8k) b R5 Resistor 0k, % R6 Resistor 0k, % R7 Current Sense Resistor WSLP06R0000DEA 0R0 06 Vishay 50 R8 Resistor k5, % R9 Resistor k5, % T Power Transformer :: + (Aux) E/6/6+I 5 U IBC Control IC SiP05/06 TSSOP-6 Vishay 5 U Temperature Sensor LM6CIMM 55 Z Micropower Voltage Reference LM0. V, 0. % SOT-5 National Semi S-777-Rev. A, -Oct-07 9

10 SiP05/06DB TABLE - BASE BOARD PARTS LIST Item Designator Part Number Manufacturer C EEUEDC70 Panasonic C EEUEDC70 Panasonic C Phycomp D BAS6 Philips 5 D BAS6 Philips 6 F 6FF5-R Bussmann 7 J 7706 Phoenix Contact 8 J 7700 Phoenix Contact 9 J 7705 Phoenix Contact 0 J R6000 Radiall J5 H8-05 Harwin J6 H8-05 Harwin J7 H8-05 Harwin J Mill-Max 5 J Mill-Max 6 Q MMUNLTG ON Semi 7 R 6K 06 8 R K S ET0MDABE C&K 0 TP 0-7 Vero TP 0-7 Vero TP 0-7 Vero TP 0-7 Vero 0 S-777-Rev. A, -Oct-07

11 SiP05/06DB D 6 5 Only populate on feedforward version HYST 5 OS GND Vtemp V+ U LM6 C PolarPAK or PowerPAK options Q Q R R R6 R5 R0 R9 R C6 C C C5 C7 C8 C0 R7 D7 C7 Q7 D8 C8 R8 R MILL_MAX 0_PIN J- J- MILL_MAX 0_PIN J- MILL_MAX 0_PIN C Vcc Comp CS GND Vref Rosc Cosc Rdb U Vin Vindet BST DH LX DL PGND SS MUNTZ 5 Z Q6 Q9 T-B T-A T-G 6 5 T-H 8 7 CS SHDN VCC VCC SHDN T-I VCC CS VCC Figure 8. Schematic - Primary Side S-777-Rev. A, -Oct-07

12 SiP05/06DB L IHLP00 60 nh Feedforward version only Q Q Q5 Q0 D5 Q PolarPAK or PowerPAK options C + C5 R5 R9 R6 Q8 D9 D0 C J MILL_MAX 58_PIN J5 MILL_MAX 58_PIN 5 T-C 7 6 T-D T-E T-F SECGND SECGND Figure 9. Schematic - Secondary Side S-777-Rev. A, -Oct-07

13 SiP05/06DB TP TESTPOINT_LOOP TP TESTPOINT_LOOP PRI_GND VIN_REFUSE VIN J-A SCREW_TERMINAL_WAY J-B SCREW_TERMINAL_WAY J-C SCREW_TERMINAL_WAY J-D SCREW_TERMINAL_WAY VIN_REFUSE C C PRI_GND F J5- PIN_RECEPTICLE J6- PIN_RECEPTICLE J8 PIN_RECEPTIBLE_HICURRENT SCREW_TERMINAL_6WAY J- SCREW_TERMINAL_6WAY J- SCREW_TERMINAL_6WAY J- C SCREW_TERMINAL_6WAY J- SEC_VOUT SEC_GND J SMC_CONN 5 TP- TESTPOINT_LOOP TP- TESTPOINT_LOOP VIN J9 SCREW_TERMINAL_6WAY J-5 SEC_GND R S D PIN_RECEPTIBLE_HICURRENT J-6 SCREW_TERMINAL_6WAY SEC_VOUT R PRI_GND PRI_GND J7- PIN_RECEPTICLE J- SCREW_TERMINAL_WAY J- SCREW_TERMINAL_WAY D PRI_GND Q Figure 0. Schematic - Base Board maintains worldwide manufacturing capability. Products may be manufactured at one of several qualified locations. Reliability data for Silicon Technology and Package Reliability represent a composite of all qualified locations. For related documents such as package/tape drawings, part marking, and reliability data, see S-777-Rev. A, -Oct-07