2011年1月28日に発表しました「SPICEの活用方法」の資料です。このデータは、パワー・ポイント版になります。お問い合わせは、ビー・テクノロジーまで。info@bee-tech.com

1. Copyright (C) Bee Technologies Inc. 2011 1 SPICEの活用方法 「コンセプトキット」でパラメータベース・シミュレーション 1.PWM Buck Converter Average Model←[DEMO] フィードバック制御におけるアベレージモデルを活用した 位相余裕度のシミュレーションの活用方法を解説していきます。2.ステッピングモータのコンセプトキット [事例紹介]2.1 ユニポーラ・ステッピングモーター制御回路2.2 バイポーラ・ステッピングモーター制御回路 2011年1月28日(金曜日) 株式会社ビー・テクノロジーhttp://www.bee-tech.com/horigome@bee-tech.com

2. コンセプトキットの位置付け Copyright (C) Bee Technologies Inc. 2011 2 [スパイスモデル]デバイスモデリングサービス(58種類のデバイスモデリング) スパイス・パーク www.spicepark.com シンプルモデル(NEW)←ブロックベースのスパイスモデル [デザインキット]回路方式のテンプレート コンセプトキット(NEW)←(概念設計のテンプレート) デザインキット(各回路方式のテンプレート) 回路解析シミュレータSpice 系回路解析シミュレータPSpice,LTspice,MultiSim,MicroCap,HSPICE,SmartSPICE,Simplorer, and so on

3. コンセプトキットとは Copyright (C) Bee Technologies Inc. 2011 3

4. デザインキット Copyright (C) Bee Technologies Inc. 2011 4 要望が多いインバータ回路方式を中心に20種類の新製品を開発中。

5. Concept Kit:PWM Buck Converter Average Model Copyright (C) Bee Technologies Inc. 2011 5

6. Contents Concept of Simulation Buck Converter Circuit Averaged Buck Switch Model Buck Regulator Design Workflow Setting PWM Controller’s Parameters. Programming Output Voltage: Rupper, Rlower Inductor Selection: L Capacitor Selection: C, ESR Stabilizing the Converter (Example) Load Transient Response Simulation (Example) Appendix Type 2 Compensation Calculation using Excel Feedback Loop Compensators Simulation Index Copyright (C) Bee Technologies Inc. 2011 6

8. C

9. ESR

11. VREFVOUT VREF Models:

12. Buck Converter Circuit Copyright (C) Bee Technologies Inc. 2011 8 Power Switches Filter & Load PWM Controller

16. Step2: Set C1=1kF, C2=1fF, (always keep the default value) and R2= calculated value (Rupper//Rlower) as the initial values.

17. Step3: Select a crossover frequency (about 10kHz or fc < fosc/4). Then complete the table.

18. Step4: Read the Gain and Phase value at the crossover frequency (10kHz) from the Bode plot, Then put the values to the table

19. Step5: Select the phase margin at the fc ( > 45 ). Then change the K value until it gives the satisfied phase margin, for this example K=6 is chosen for Phase margin = 46.

20. Remark: If K-factor fail to gives the satisfied phase margin, Increase the output capacitor C then try Step1 to Step5 again.5 Load Transient Response Simulation 6

21. Buck Regulator Design Workflow Copyright (C) Bee Technologies Inc. 2011 11 3 4 5 2 1

23. VP= (Error Amp. Gain  vFB ) / d

24. vFB = vFBH – vFBL

25. d = dMAX – dMIN

26. Error Amp. Gain is 100 (approximated) where VP is the sawtooth peak voltage. vFBH is maximum FB voltage where d = 0 vFBL is minimum FB voltage where d =1(100%) dMAX is maximum duty cycle, e.g. d = 0(0%) dMIN is minimum duty cycle, e.g. d =1(100%) Setting PWM Controller’s Parameters Copyright (C) Bee Technologies Inc. 2011 12 1 The PWM block is used to transfer the error voltage (between FB and REF) to be the duty cycle.  If vFBH and vFBLare not provided, the default value, VP=2.5 could be used.

27. Copyright (C) Bee Technologies Inc. 2011 13 Setting PWM Controller’s Parameters (Example) 1  If the VP ( sawtooth signal amplitude ) does not informed by the datasheet, It can be approximated from the characteristics below. from VP= (Error Amp. Gain  vFB )/d Error Amp. Gain = 100 (approximated) from the graph on the left, vFB= 25mV (15m - (-10m)) d = 1 – 0 = 1 VP ≈ ( 100  25mV )/1 ≈ 2.5V vFBH vFB = 25mV vFBL d = 1 (100%) dMIN dMAX LM2575: Feedback Voltage vs. Duty Cycle  If vFBH and vFBLare not provided, the default value, VP=2.5 could be used.

30. VI,max is input maximum voltage

31. RL,min is load resistance at the minimum output current ( IOUT,min )

32. fosc is switching frequency3

33. Inductor Selection: L (Example) Copyright (C) Bee Technologies Inc. 2011 16 Inductor Value from Given: VI,max = 40V, VOUT = 5V IOUT,min = 0.2A RL,min = (VOUT /IOUT,min ) = 25 fosc = 52kHz Then: LCCM 210(uH), L = 330(uH) is selected 3

35. Capacitor Selection: C, ESR (Example) Copyright (C) Bee Technologies Inc. 2011 18 Capacitor Value From and Given: VI, max = 40 V VOUT = 5 V L (H) = 330 Then: C 188 (F) In addition: ESR 100m 4

38. Copyright (C) Bee Technologies Inc. 2011 21 Stabilizing the Converter (Example) 5 The element of the Type 2 compensator ( R2, C1, and C2 ), that stabilize the converter, can be extracted by using Type 2 Compensator Calculator (Excel sheet) and open-loop simulation with the Average Switch Models (ac models). Step2 Set C1=1kF, C2=1fF, and R2=calculated value (Rupper//Rlower) as the initial values. Step1 Open the loop with LoL=1kH and CoL=1kF then inject an AC signal to generate Bode plot.  C1=1kF is AC shorted, and C2 1fF is AC opened (or Error-Amp without compensator).

39. Stabilizing the Converter (Example) Copyright (C) Bee Technologies Inc. 2011 22 5 Step3 Select a crossover frequency (about 10kHz or fc < fosc/4 ), for this example, 10kHz is selected. Then complete the table. values from 2 Calculated value of the Rupper//Rlower values from 1

40. Copyright (C) Bee Technologies Inc. 2011 23 Stabilizing the Converter (Example) 5 Gain: T(s) = H(s)GPWM Step4 Read the Gain and Phase value at the crossover frequency(10kHz) from the Bode plot, Then put the values to the table. Phase  atfc Tip: To bring cursor to the fc = 10kHz type “ sfxv(10k) ” in Search Command. Cursor Search

41. Stabilizing the Converter (Example) Copyright (C) Bee Technologies Inc. 2011 24 5 Step5 Select the phase margin at fc (> 45 ). Then change the K value (start from K=2) until it gives the satisfied phase margin, for this example K=6 is chosen for Phase margin = 46. As the result; R2, C1, and C2 are calculated. Remark: If K-factor fail to gives the satisfied phase margin, Increase the output capacitor C then try Step1 to Step5 again.  K Factor enable the circuit designer to choose a loop cross-over frequency and phase margin, and then determine the necessary component values to achieve these results. A very big K value (e.g. K > 100) acts like no compensator (C1 is shorted and C2 is opened).

42. Stabilizing the Converter (Example) Copyright (C) Bee Technologies Inc. 2011 25 5 The element of the Type 2 compensator ( R2, C1, and C2 ) extraction can be completed by Type 2 Compensator Calculator (Excel sheet) with the converter average models (ac models) and open-loop simulation. The calculated values of the type 2 elements are, R2=122.780k, C1=0.778nF, and C2=21.6pF. *Analysis directives: .AC DEC 100 0.1 10MEG

43. Copyright (C) Bee Technologies Inc. 2011 26 Stabilizing the Converter (Example) 5 Gain and Phase responses after stabilizing Gain: T(s) = H(s) G(s)GPWM Phase  atfc Phase margin = 45.930 at the cross-over frequency - fc = 9.778kHz. Tip: To bring cursor to the cross-over point (gain = 0dB) type “ sfle(0) ” in Search Command. Cursor Search

44. Load Transient Response Simulation (Example) Copyright (C) Bee Technologies Inc. 2011 27 The converter, that have been stabilized, are connected with step-load to perform load transient response simulation. 5V/2.5 = 0.2A step to 0.2+0.8=1.0A load *Analysis directives: .TRAN 0 20ms 0 1u

46. Copyright (C) Bee Technologies Inc. 2011 30 B. Feedback Loop Compensators Type1 Compensator Type2 Compensator Type2a Compensator Type2b Compensator Type3 Compensator

48. Copyright (C) Bee Technologies Inc. 2011 33 Unipolar Stepping Motor Drive Circuit

51. Two-Phase

53. RModels:

54. 2.Unipolar Stepping Motor Drive Circuit Copyright (C) Bee Technologies Inc. 2011 35 Signal generator Hysteresis Based Current Controller Switches Supply Voltage Unipolar Stepping Motor

55. 3.Unipolar Stepping Motor Copyright (C) Bee Technologies Inc. 2011 36 The electrical equivalent circuit of each phase consists of an inductance of the phase winding series with resistance. The inductance is ideal (without saturation characteristics and the mutual inductance between phases) The motor back EMF is set as zero to simplified the model parameters extraction. Input the inductance and resistance values (parameter: L, R) of the stepping motor, that are usually provided by the manufacturer datasheet, to generally model the phase winding.

56. 4.Switches Copyright (C) Bee Technologies Inc. 2011 37 A near-ideal DIODE can be modeled by using spice primitive model (D), which parameter: N=0.01 RS=0. A near-ideal MOSFET can be modeled by using PSpice VSWITCH that is voltage controlled switch. The parameter RON represents Rds(on) characteristics of MOSFET, that are usually provide by the manufacturer datasheet. The value could be about 10m to 10 ohm.

60. Reduces motor resonance which could cause a motor to stall at a resonant frequency.

62. 5.2 Two-Phase Sequence Copyright (C) Bee Technologies Inc. 2011 40 Clock Phase A ON Phase /A ON Phase B ON Phase /B ON ON 1 Sequence

63. 5.3 Half-Step Sequence Copyright (C) Bee Technologies Inc. 2011 41 Clock Phase A ON Phase /A ON Phase B ON Phase /B ON 1 Sequence

64. 6.Hysteresis-Based Current Controller Copyright (C) Bee Technologies Inc. 2011 42 Controlled by the signal from the microcontroller. Generate the switch (MOSFET) drive signal by comparing the measured phase current with their references. Input the reference value at the I_SET (e.g. I_SET=0.5A) to set the regulated current level. The hysteresis current value is set at the VHYS (e.g. VHYS=0.1A).

65. 7.1 One-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 43 One-Phase Step Sequence Generator (100 pps) *Analysisdirectives: .TRAN 0 40ms 0 10u

66. 7.1 One-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 44 Clock Phase A Current I_HYS=0.1A I_SET=0.5A Phase /A Current Phase B Current Phase /B Current

67. 7.2 Two-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 45 Two-Phase Step Sequence Generator (100 pps) *Analysisdirectives: .TRAN 0 40ms 0 10u SKIPBP .OPTIONS ITL4= 40

68. 7.2 Two-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 46 Clock Phase A Current I_HYS=0.1A I_SET=0.5A Phase /A Current Phase B Current Phase /B Current

69. 7.3 Half-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 47 Half-Phase Step Sequence Generator (100 pps) *Analysisdirectives: .TRAN 0 80ms 0 10u SKIPBP .OPTIONS ITL4= 40

70. 7.3 Half-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 48 Clock Phase A Current I_HYS=0.1A I_SET=0.5A Phase /A Current Phase B Current Phase /B Current

71. 8.Drive Circuit Efficiency (%) Copyright (C) Bee Technologies Inc. 2011 49 Half-Phase Step Sequence Generator (100 pps) *Analysisdirectives: .TRAN 0 40ms 0ms 10u SKIPBP .STEP PARAM RON LIST 10m, 100m, 1 .OPTIONS ITL4= 40

72. 8.Drive Circuit Efficiency (%) Copyright (C) Bee Technologies Inc. 2011 50 at switches Ron = 10m, (99.6%) at switches Ron = 100m, (99.3%) at switches Ron = 1,(95.9%) Note: Add trace 100*AVG(W(U1))/(-AVG(W(Vcc))) for the Efficiency.

73. Copyright (C) Bee Technologies Inc. 2011 51 Bipolar Stepping Motor Drive Circuit

74. Bipolar Stepping Motor Drive Circuit Contents Concept of Simulation Unipolar Stepping Motor Drive Circuit Unipolar Stepping Motor Switches Signal Generator Hysteresis-Based Current Controller Unipolar Stepping Motor Drive Circuit (Example) 7.1 One-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A 7.2 Two-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A 7.3 Half-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Drive Circuit Efficiency Copyright (C) Bee Technologies Inc. 2011 52

77. Two-Phase

79. RModels:

80. Signal generator Hysteresis Based Current Controller 2.Unipolar Stepping Motor Drive Circuit Copyright (C) Bee Technologies Inc. 2011 54 Bipolar Stepping Motor H-Bridge Switches (Driver) Supply Voltage

81. 3.Bipolar Stepping Motor Copyright (C) Bee Technologies Inc. 2011 55 The electrical equivalent circuit of each phase consists of an inductance of the phase winding series with resistance. The inductance is ideal (without saturation characteristics and the mutual inductance between phases) The motor back EMF is set as zero to simplified the model parameters extraction. Input the inductance and resistance values (parameter: L, R) of the stepping motor, that are usually provided by the manufacturer datasheet, to generally model the phase winding.

82. 4.Switches Copyright (C) Bee Technologies Inc. 2011 56 A near-ideal DIODE can be modeled by using spice primitive model (D), which parameter: N=0.01 RS=0. A near-ideal MOSFET can be modeled by using PSpice VSWITCH that is voltage controlled switch. MOSFETs are used as a H-Bridge. The parameter RON represents Rds(on) characteristics of MOSFET, that are usually provide by the manufacturer datasheet. The value could be about 10m to 10 ohm.

86. Reduces motor resonance which could cause a motor to stall at a resonant frequency.

88. 5.2 Two-Phase Sequence Copyright (C) Bee Technologies Inc. 2011 59 Clock Phase A ON Phase /A ON Phase B ON Phase /B ON ON 1 Sequence

89. 5.3 Half-Step Sequence Copyright (C) Bee Technologies Inc. 2011 60 Clock Phase A ON Phase /A ON Phase B ON Phase /B ON 1 Sequence

90. 6.Hysteresis-Based Current Controller Copyright (C) Bee Technologies Inc. 2011 61 Controlled by the signal from the microcontroller. Generate the switch (MOSFET) drive signal by comparing the measured phase current with their references. Input the reference value at the I_SET (e.g. I_SET=0.5A) to set the regulated current level. The hysteresis current value is set at the VHYS (e.g. VHYS=0.1A).

91. 7.1 One-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 62 One-Phase Step Sequence Generator (100 pps) *Analysisdirectives: .TRAN 0 80ms 0 10u SKIPBP .OPTIONS ITL4= 40

92. 7.1 One-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 63 Clock Phase A Current I_HYS=0.1A I_SET=0.5A Phase /A Current Phase B Current Phase /B Current

93. 7.2 Two-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 64 One-Phase Step Sequence Generator (100 pps) *Analysisdirectives: .TRAN 0 80ms 0 10u SKIPBP .OPTIONS ITL4= 40

94. 7.2 One-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 65 Clock Phase A Current I_HYS=0.1A I_SET=0.5A Phase /A Current Phase B Current Phase /B Current

95. 7.3 Half-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 66 One-Phase Step Sequence Generator (100 pps) *Analysisdirectives: .TRAN 0 160ms 0 10u SKIPBP .OPTIONS ITL4= 40

96. 7.3 One-Phase Sequence Drive, IPHASE=0.5A, IRIPPLE=0.1A Copyright (C) Bee Technologies Inc. 2011 67 Clock Phase A Current I_HYS=0.1A I_SET=0.5A Phase /A Current Phase B Current Phase /B Current

97. 8.Drive Circuit Efficiency (%) Copyright (C) Bee Technologies Inc. 2011 68 One-Phase Step Sequence Generator (100 pps) *Analysisdirectives: .TRAN 0 80ms 0 10u SKIPBP .STEP PARAM RON LIST 10m, 100m, 1 .OPTIONS ITL4= 40

98. 8.Drive Circuit Efficiency (%) Copyright (C) Bee Technologies Inc. 2011 69 at switches Ron = 10m, (99.7%) at switches Ron = 100m, (99.8%) at switches Ron = 1, (86%) Note: Add trace 100*AVG(W(U1))/(-AVG(W(Vcc))) for the Efficiency.

99. Bee Technologies Group デバイスモデリング スパイス・パーク(スパイスモデル・ライブラリー) シンプルモデル(準備中) デザインキット コンセプトキット(準備中) デバイスモデリング教材 【本社】 株式会社ビー・テクノロジー 〒105-0012 東京都港区芝大門二丁目2番7号 7セントラルビル4階 代表電話: 03-5401-3851 設立日:2002年9月10日 資本金:8,830万円 【子会社】 Bee Technologies Corporation (アメリカ) Siam Bee Technologies Co.,Ltd. (タイランド) 本ドキュメントは予告なき変更をする場合がございます。 ご了承下さい。また、本文中に登場する製品及びサービスの名称は全て関係各社または個人の各国における商標または登録商標です。本原稿に関するお問い合わせは、当社にご連絡下さい。 お問合わせ先) info@bee-tech.com 70 Copyright (C) Bee Technologies Inc. 2011