Order this document by MC34167/D The MC34167, MC33167 series are high performance fixed frequency power switching regulators that contain the primary functions required for dc–to–dc converters. This series was specifically designed to be incorporated in step–down and voltage–inverting configurations with a minimum number of external components and can also be used cost effectively in step–up applications. These devices consist of an internal temperature compensated reference, fixed frequency oscillator with on–chip timing components, latching pulse width modulator for single pulse metering, high gain error amplifier, and a high current output switch. Protective features consist of cycle–by–cycle current limiting, undervoltage lockout, and thermal shutdown. Also included is a low power standby mode that reduces power supply current to 36 µA. • Output Switch Current in Excess of 5.0 A • • • • • • • • • • • POWER SWITCHING REGULATORS SEMICONDUCTOR TECHNICAL DATA TH SUFFIX PLASTIC PACKAGE CASE 314A Fixed Frequency Oscillator (72 kHz) with On–Chip Timing Provides 5.05 V Output without External Resistor Divider 1 5 Precision 2% Reference 0% to 95% Output Duty Cycle 1 TV SUFFIX PLASTIC PACKAGE CASE 314B Cycle–by–Cycle Current Limiting 5 Undervoltage Lockout with Hysteresis Internal Thermal Shutdown Heatsink surface connected to Pin 3. Operation from 7.5 V to 40 V Standby Mode Reduces Power Supply Current to 36 µA Economical 5–Lead TO–220 Package with Two Optional Leadforms Also Available in Surface Mount D2PAK Package T SUFFIX PLASTIC PACKAGE CASE 314D 1 5 Pin 1. 2. 3. 4. 5. Simplified Block Diagram (Step Down Application) Voltage Feedback Input Switch Output Ground Input Voltage/VCC Compensation/Standby Vin D2T SUFFIX PLASTIC PACKAGE CASE 936A (D2PAK) 4 ILIMIT 1 Oscillator 5 S Q Heatsink surface (shown as terminal 6 in case outline drawing) is connected to Pin 3. 2 R PWM ORDERING INFORMATION UVLO Thermal L Reference EA 1 3 5 This device contains 143 active transistors. VO 5.05 V/5.0 A Device Operating Temperature Range Surface Mount Straight Lead Horiz. Mount Vertical Mount MC34167D2T MC34167T MC34167TH MC34167TV Surface Mount Straight Lead Horiz. Mount Vertical Mount TA = 0° to + 70°C Motorola, Inc. 1996 MOTOROLA ANALOG IC DEVICE DATA Package MC33167D2T MC33167T TA = – 40° to +85°C MC33167TH MC33167TV Rev 3 1 MC34167 MC33167 MAXIMUM RATINGS Rating Symbol Power Supply Input Voltage Value Unit VCC 40 V VO(switch) –2.0 to + Vin V VFB, VComp –1.0 to + 7.0 V PD θJA θJC PD θJA θJC Internally Limited 65 5.0 Internally Limited 70 5.0 W °C/W °C/W W °C/W °C/W Operating Junction Temperature TJ +150 °C Operating Ambient Temperature (Note 3) MC34167 MC33167 TA Switch Output Voltage Range Voltage Feedback and Compensation Input Voltage Range Power Dissipation Case 314A, 314B and 314D (TA = +25°C) Thermal Resistance, Junction–to–Ambient Thermal Resistance, Junction–to–Case Case 936A (D2PAK) (TA = +25°C) Thermal Resistance, Junction–to–Ambient Thermal Resistance, Junction–to–Case °C 0 to + 70 – 40 to + 85 Storage Temperature Range Tstg – 65 to +150 °C ELECTRICAL CHARACTERISTICS (VCC = 12 V, for typical values TA = +25°C, for min/max values TA is the operating ambient temperature range that applies [Notes 2, 3], unless otherwise noted.) Characteristic Symbol Min Typ Max Unit TA = +25°C TA = Tlow to Thigh fOSC 65 62 72 – 79 81 kHz TA =+ 25°C TA = Tlow to Thigh VFB(th) 4.95 4.85 5.05 – 5.15 5.20 V Regline – 0.03 0.078 %/V OSCILLATOR Frequency (VCC = 7.5 V to 40 V) ERROR AMPLIFIER Voltage Feedback Input Threshold Line Regulation (VCC = 7.5 V to 40 V, TA = +25°C) Input Bias Current (VFB = VFB(th) + 0.15 V) Power Supply Rejection Ratio (VCC = 10 V to 20 V, f = 120 Hz) Output Voltage Swing High State (ISource = 75 µA, VFB = 4.5 V) Low State (ISink = 0.4 mA, VFB = 5.5 V) IIB – 0.15 1.0 µA PSRR 60 80 – dB VOH VOL 4.2 – 4.9 1.6 – 1.9 V DC(max) DC(min) 92 0 95 0 100 0 % Vsat – (VCC –1.5) (VCC –1.8) V PWM COMPARATOR Duty Cycle (VCC = 20 V) Maximum (VFB = 0 V) Minimum (VComp = 1.9 V) SWITCH OUTPUT Output Voltage Source Saturation (VCC = 7.5 V, ISource = 5.0 A) Isw(off) – 0 100 µA Ipk(switch) 5.5 6.5 8.0 A tr tf – – 100 50 200 100 Startup Threshold (VCC Increasing, TA = +25°C) Vth(UVLO) 5.5 5.9 6.3 V Hysteresis (VCC Decreasing, TA = +25°C) VH(UVLO) 0.6 0.9 1.2 V – – 36 40 100 60 µA mA Off–State Leakage (VCC = 40 V, Pin 2 = Gnd) Current Limit Threshold (VCC = 7.5 V) Switching Times (VCC = 40 V, Ipk = 5.0 A, L = 225 µH, TA = +25°C) Output Voltage Rise Time Output Voltage Fall Time ns UNDERVOLTAGE LOCKOUT TOTAL DEVICE Power Supply Current (TA = +25°C ) Standby (VCC = 12 V, VComp < 0.15 V) Operating (VCC = 40 V, Pin 1 = Gnd for maximum duty cycle) ICC NOTES: 1. Maximum package power dissipation limits must be observed to prevent thermal shutdown activation. 2. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible. 3. Tlow = 0°C for MC34167 Thigh = + 70°C for MC34167 = – 40°C for MC33167 = + 85°C for MC33167 2 MOTOROLA ANALOG IC DEVICE DATA Figure 1. Voltage Feedback Input Threshold versus Temperature Figure 2. Voltage Feedback Input Bias Current versus Temperature 5.25 100 VCC = 12 V VFB(th) Max = 5.15 V I IB, INPUT BIAS CURRENT (nA) V FB(th), VOLTAGE FEEDBACK INPUT THRESHOLD (V) MC34167 MC33167 5.17 5.09 VFB(th) Typ = 5.05 V 5.01 VFB(th) Min = 4.95 V 4.93 4.85 – 55 – 25 0 25 50 75 TA, AMBIENT TEMPERATURE (°C) 100 VCC = 12 V VFB = VFB(th) 80 60 40 20 0 – 55 125 80 Gain 0 30 60 60 40 90 Phase 20 120 0 150 – 20 10 100 1.0 k 10 k 100 k f, FREQUENCY (Hz) 1.0 M 180 10 M 125 1.6 1.2 0.8 VCC = 12 V VFB = 5.5 V TA = +25°C 0.4 0 Figure 5. Oscillator Frequency Change versus Temperature 0.4 0.8 1.2 1.6 ISink, OUTPUT SINK CURRENT (mA) 2.0 Figure 6. Switch Output Duty Cycle versus Compensation Voltage 100 4.0 VCC = 12 V 0 – 4.0 – 8.0 – 12 – 55 100 2.0 0 DC, SWITCH OUTPUT DUTY CYCLE (%) ∆ f OSC , OSCILLATOR FREQUENCY CHANGE (%) VCC = 12 V VComp = 3.25 V RL = 100 k TA = +25°C Vsat , OUTPUT SATURATION VOLTAGE (V) 100 0 25 50 75 TA, AMBIENT TEMPERATURE (°C) Figure 4. Error Amp Output Saturation versus Sink Current φ, EXCESS PHASE (DEGREES) A VOL , OPEN LOOP VOLTAGE GAIN (dB) Figure 3. Error Amp Open Loop Gain and Phase versus Frequency – 25 – 25 0 25 50 75 100 TA, AMBIENT TEMPERATURE (°C) MOTOROLA ANALOG IC DEVICE DATA 125 80 VCC = 12 V TA = +25°C 60 40 20 0 1.5 2.0 2.5 3.0 3.5 4.0 VComp, COMPENSATION VOLTAGE (V) 4.5 3 Figure 7. Switch Output Source Saturation versus Source Current Figure 8. Negative Switch Output Voltage versus Temperature 0 0 VCC Vsw, SWITCH OUTPUT VOLTAGE (V) Vsat, SWITCH OUTPUT SOURCE SATURATION (V) MC34167 MC33167 – 0.5 TA = +25°C –1.0 –1.5 – 2.0 – 2.5 – 3.0 0 2.0 4.0 6.0 ISource, SWITCH OUTPUT SOURCE CURRENT (A) Gnd – 0.2 VCC = 12 V Pin 5 = 2.0 V Pins 1, 3 = Gnd Pin 2 Driven Negative – 0.4 – 0.6 – 0.8 Isw = 10 mA –1.0 –1.2 – 55 8.0 I pk(switch), CURRENT LIMIT THRESHOLD (A) Figure 9. Switch Output Current Limit Threshold versus Temperature I CC , SUPPLY CURRENT ( µ A) 6.8 6.4 6.0 V th(UVLO) , UNDERVOLTAGE LOCKOUT THRESHOLD (V) 100 125 – 25 0 25 50 75 TA, AMBIENT TEMPERATURE (°C) 100 Pin 4 = VCC Pins 1, 3, 5 = Gnd Pin 2 Open TA = +25°C 120 80 40 0 0 125 Figure 11. Undervoltage Lockout Thresholds versus Temperature 10 20 30 VCC, SUPPLY VOLTAGE (V) 40 Figure 12. Operating Supply Current versus Supply Voltage 6.5 50 I CC, SUPPLY CURRENT (mA) Startup Threshold VCC Increasing 6.0 5.5 Turn–Off Threshold VCC Decreasing 5.0 4.5 4 0 25 50 75 TA, AMBIENT TEMPERATURE (°C) 160 VCC = 12 V Pins 1, 2, 3 = Gnd 4.0 – 55 – 25 Figure 10. Standby Supply Current versus Supply Voltage 7.2 5.6 – 55 Isw = 100 µA – 25 0 25 50 75 TA, AMBIENT TEMPERATURE (°C) 100 125 40 30 20 Pin 4 = VCC Pins 1, 3 = Gnd Pins 2, 5 Open TA = +25°C 10 0 0 10 20 30 VCC, SUPPLY VOLTAGE (V) 40 MOTOROLA ANALOG IC DEVICE DATA MC34167 MC33167 Figure 13. MC34167 Representative Block Diagram Vin Current Sense + 4 Input Voltage/VCC Cin Oscillator S CT Switch Output Q R Pulse Width Modulator 2 Undervoltage Lockout PWM Latch Thermal Shutdown L 5.05 V Reference + + Error Amp 100 µA 1 120 Gnd 3 Compensation = 5 Voltage Feedback Input CF Sink Only Positive True Logic R2 VO CO RF R1 Figure 14. Timing Diagram 4.1 V Timing Capacitor CT Compensation 2.3 V ON Switch Output OFF MOTOROLA ANALOG IC DEVICE DATA 5 MC34167 MC33167 INTRODUCTION The MC34167, MC33167 series are monolithic power switching regulators that are optimized for dc–to–dc converter applications. These devices operate as fixed frequency, voltage mode regulators containing all the active functions required to directly implement step–down and voltage–inverting converters with a minimum number of external components. They can also be used cost effectively in step–up converter applications. Potential markets include automotive, computer, industrial, and cost sensitive consumer products. A description of each section of the device is given below with the representative block diagram shown in Figure 13. Oscillator The oscillator frequency is internally programmed to 72 kHz by capacitor CT and a trimmed current source. The charge to discharge ratio is controlled to yield a 95% maximum duty cycle at the Switch Output. During the discharge of CT, the oscillator generates an internal blanking pulse that holds the inverting input of the AND gate high, disabling the output switch transistor. The nominal oscillator peak and valley thresholds are 4.1 V and 2.3 V respectively. Pulse Width Modulator The Pulse Width Modulator consists of a comparator with the oscillator ramp voltage applied to the noninverting input, while the error amplifier output is applied into the inverting input. Output switch conduction is initiated when CT is discharged to the oscillator valley voltage. As CT charges to a voltage that exceeds the error amplifier output, the latch resets, terminating output transistor conduction for the duration of the oscillator ramp–up period. This PWM/Latch combination prevents multiple output pulses during a given oscillator clock cycle. Figures 6 and 14 illustrate the switch output duty cycle versus the compensation voltage. Current Sense The MC34167 series utilizes cycle–by–cycle current limiting as a means of protecting the output switch transistor from overstress. Each on cycle is treated as a separate situation. Current limiting is implemented by monitoring the output switch transistor current buildup during conduction, and upon sensing an overcurrent condition, immediately turning off the switch for the duration of the oscillator ramp–up period. The collector current is converted to a voltage by an internal trimmed resistor and compared against a reference by the Current Sense comparator. When the current limit threshold is reached, the comparator resets the PWM latch. The current limit threshold is typically set at 6.5 A. Figure 9 illustrates switch output current limit threshold versus temperature. Error Amplifier and Reference A high gain Error Amplifier is provided with access to the inverting input and output. This amplifier features a typical dc voltage gain of 80 dB, and a unity gain bandwidth of 600 kHz with 70 degrees of phase margin (Figure 3). The noninverting input is biased to the internal 5.05 V reference and is not pinned out. The reference has an accuracy of ± 2.0% at room temperature. To provide 5.0 V at the load, the reference is programmed 50 mV above 5.0 V to compensate for a 1.0% voltage drop in the cable and connector from the 6 converter output. If the converter design requires an output voltage greater than 5.05 V, resistor R1 must be added to form a divider network at the feedback input as shown in Figures 13 and 18. The equation for determining the output voltage with the divider network is: Vout + 5.05 ǒ )Ǔ R2 R1 1 External loop compensation is required for converter stability. A simple low–pass filter is formed by connecting a resistor (R2) from the regulated output to the inverting input, and a series resistor–capacitor (RF, CF) between Pins 1 and 5. The compensation network component values shown in each of the applications circuits were selected to provide stability over the tested operating conditions. The step–down converter (Figure 18) is the easiest to compensate for stability. The step–up (Figure 20) and voltage–inverting (Figure 22) configurations operate as continuous conduction flyback converters, and are more difficult to compensate. The simplest way to optimize the compensation network is to observe the response of the output voltage to a step load change, while adjusting RF and CF for critical damping. The final circuit should be verified for stability under four boundary conditions. These conditions are minimum and maximum input voltages, with minimum and maximum loads. By clamping the voltage on the error amplifier output (Pin 5) to less than 150 mV, the internal circuitry will be placed into a low power standby mode, reducing the power supply current to 36 µA with a 12 V supply voltage. Figure 10 illustrates the standby supply current versus supply voltage. The Error Amplifier output has a 100 µA current source pull–up that can be used to implement soft–start. Figure 17 shows the current source charging capacitor CSS through a series diode. The diode disconnects CSS from the feedback loop when the 1.0 M resistor charges it above the operating range of Pin 5. Switch Output The output transistor is designed to switch a maximum of 40 V, with a minimum peak collector current of 5.5 A. When configured for step–down or voltage–inverting applications, as in Figures 18 and 22, the inductor will forward bias the output rectifier when the switch turns off. Rectifiers with a high forward voltage drop or long turn on delay time should not be used. If the emitter is allowed to go sufficiently negative, collector current will flow, causing additional device heating and reduced conversion efficiency. Figure 8 shows that by clamping the emitter to 0.5 V, the collector current will be in the range of 100 µA over temperature. A 1N5825 or equivalent Schottky barrier rectifier is recommended to fulfill these requirements. Undervoltage Lockout An Undervoltage Lockout comparator has been incorporated to guarantee that the integrated circuit is fully functional before the output stage is enabled. The internal reference voltage is monitored by the comparator which enables the output stage when VCC exceeds 5.9 V. To prevent erratic output switching as the threshold is crossed, 0.9 V of hysteresis is provided. MOTOROLA ANALOG IC DEVICE DATA MC34167 MC33167 Thermal Protection Internal Thermal Shutdown circuitry is provided to protect the integrated circuit in the event that the maximum junction temperature is exceeded. When activated, typically at 170°C, the latch is forced into a ‘reset’ state, disabling the output switch. This feature is provided to prevent catastrophic failures from accidental device overheating. It is not intended to be used as a substitute for proper heatsinking. The MC34167 is contained in a 5–lead TO–220 type package. The tab of the package is common with the center pin (Pin 3) and is normally connected to ground. DESIGN CONSIDERATIONS Do not attempt to construct a converter on wire–wrap or plug–in prototype boards. Special care should be taken to separate ground paths from signal currents and ground paths from load currents. All high current loops should be kept as short as possible using heavy copper runs to minimize ringing and radiated EMI. For best operation, a tight component layout is recommended. Capacitors Cin, CO, and all feedback components should be placed as close to the IC as physically possible. It is also imperative that the Schottky diode connected to the Switch Output be located as close to the IC as possible. Figure 16. Over Voltage Shutdown Circuit Figure 15. Low Power Standby Circuit + + Error Amp 100 µA 1 120 Compensation Error Amp 100 µA 120 Compensation 5 1 5 R1 R1 I = Standby Mode VShutdown = VZener + 0.7 Figure 17. Soft–Start Circuit + Error Amp 100 µA 120 Compensation D2 1 5 D1 R1 Vin 1.0 M Css tSoft–Start ≈ 35,000 Css MOTOROLA ANALOG IC DEVICE DATA 7 MC34167 MC33167 Figure 18. Step–Down Converter Vin 12 V + 4 ILIMIT + Oscillator Cin 330 S Q1 Q R 2 PWM D1 1N5825 UVLO L 190 µH Thermal Reference + + EA R2 1 5 3 Test Line Regulation Load Regulation Output Ripple Short Circuit Current Efficiency CF RF 0.1 68 k CO 4700 6.8 k VO 5.05 V/5.0 A + R1 Conditions Results Vin = 10 V to 36 V, IO = 5.0 A Vin = 12 V, IO = 0.25 A to 5.0 A 4.0 mV = ± 0.039% Vin = 12 V, IO = 5.0 A Vin = 12 V, RL = 0.1 Ω 20 mVpp Vin = 12 V, IO = 5.0 A Vin = 24 V, IO = 5.0 A 78.9% 82.6% 1.0 mV = ± 0.01% 6.5 A L = Coilcraft M1496–A or General Magnetics Technology GMT–0223, 42 turns of #16 AWG on Magnetics Inc. 58350–A2 core. Heatsink = AAVID Engineering Inc. 5903B, or 5930B. The Step–Down Converter application is shown in Figure 18. The output switch transistor Q1 interrupts the input voltage, generating a squarewave at the LCO filter input. The filter averages the squarewaves, producing a dc output voltage that can be set to any level between Vin and Vref by controlling the percent conduction time of Q1 to that of the total oscillator cycle time. If the converter design requires an output voltage greater than 5.05 V, resistor R1 must be added to form a divider network at the feedback input. Figure 19. Step–Down Converter Printed Circuit Board and Component Layout + 8 + R2 + D1 Cin R1 L CF RF + (Bottom View) – VO ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉ ÉÉÉÉÉ – CO Vin 1.9 ″ MC34167 STEP–DOWN 3.0″ (Top View) MOTOROLA ANALOG IC DEVICE DATA MC34167 MC33167 Figure 20. Step–Up/Down Converter V in 12 V + 4 ILIMIT + Oscillator Cin 330 S D1 1N5825 Q1 Q R 2 PWM L 190 µH UVLO *RG 620 D4 1N4148 Thermal Q2 MTP3055EL Reference + D3 1N967A + D2 1N5822 EA R2 1 5 3 CF RF 0.47 4.7 k *Gate resistor RG, zener diode D3, and diode D4 are required only when Vin is greater than 20 V. Test Line Regulation Load Regulation Output Ripple Short Circuit Current Efficiency CO 2200 6.8 k + VO 28 V/0.9 A R1 1.5 k Conditions Results Vin = 10 V to 24 V, IO = 0.9 A Vin = 12 V, IO = 0.1 A to 0.9 A 10 mV = ± 0.017% Vin = 12 V, IO = 0.9 A Vin = 12 V, RL = 0.1 Ω 140 mVpp Vin = 12 V, IO = 0.9 A Vin = 24 V, IO = 0.9 A 80.1% 87.8% 30 mV = ± 0.053% 6.0 A L = Coilcraft M1496–A or General Magnetics Technology GMT–0223, 42 turns of #16 AWG on Magnetics Inc. 58350–A2 core. Heatsink = AAVID Engineering Inc. MC34167: 5903B, or 5930B MTP3055EL: 5925B Figure 20 shows that the MC34167 can be configured as a step–up/down converter with the addition of an external power MOSFET. Energy is stored in the inductor during the ON time of transistors Q1 and Q2. During the OFF time, the energy is transferred, with respect to ground, to the output filter capacitor and load. This circuit configuration has two significant advantages over the basic step–up converter circuit. The first advantage is that output short circuit protection is provided by the MC34167, since Q1 is directly in series with Vin and the load. Second, the output voltage can be programmed to be less than Vin. Notice that during the OFF time, the inductor forward biases diodes D1 and D2, transferring its energy with respect to ground rather than with respect to Vin. When operating with Vin greater than 20 V, a gate protection network is required for the MOSFET. The network consists of components RG, D3, and D4. Figure 21. Step–Up/Down Converter Printed Circuit Board and Component Layout D3 MOTOROLA ANALOG IC DEVICE DATA CO D2 + Cin R1 D1 CF L R2 + RF + (Bottom View) ÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎ ÎÎÎÎÎÎ ÎÎÎ ÎÎÎÎÎÎ – – VO ÎÎ ÎÎ Î Q2 + Vin 1.9 ″ MC34167 STEP UP-DOWN 3.45″ RG (Top View) 9 MC34167 MC33167 Figure 22. Voltage–Inverting Converter Vin 12 V + 4 ILIMIT + Oscillator Cin 330 S Q1 Q R 2 PWM L 190 µH UVLO D1 1N5825 Thermal Reference + + EA R1 1 Load Regulation Output Ripple Short Circuit Current Efficiency RF 0.47 4.7 k VO –12 V/1.7 A CO 4700 + Test Line Regulation CF 5 3 2.4 k C1 R2 3.3 k Conditions 0.047 Results Vin = 10 V to 24 V, IO = 1.7 A Vin = 12 V, IO = 0.1 A to 1.7 A 15 mV = ± 0.61% Vin = 12 V, IO = 1.7 A Vin = 12 V, RL = 0.1 Ω 78 mVpp Vin = 12 V, IO = 1.7 A Vin = 24 V, IO = 1.7 A 79.5% 86.2% 4.0 mV = ± 0.020% 5.7 A L = Coilcraft M1496–A or General Magnetics Technology GMT–0223, 42 turns of #16 AWG on Magnetics Inc. 58350–A2 core. Heatsink = AAVID Engineering Inc. 5903B, or 5930B. Two potential problems arise when designing the standard voltage–inverting converter with the MC34167. First, the Switch Output emitter is limited to –1.5 V with respect to the ground pin and second, the Error Amplifier’s noninverting input is internally committed to the reference and is not pinned out. Both of these problems are resolved by connecting the IC ground pin to the converter’s negative output as shown in Figure 22. This keeps the emitter of Q1 positive with respect to the ground pin and has the effect of reversing the Error Amplifier inputs. Note that the voltage drop across R1 is equal to 5.05 V when the output is in regulation. Figure 23. Voltage–Inverting Converter Printed Circuit Board and Component Layout 3.0″ + Cin CF L R2 ÎÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ ÎÎÎ ÎÎÎÎÎ ÎÎÎÎÎ RF + 10 – + D1 Vin R1 C1 + + (Bottom View) VO – CO + 1.9 ″ MC34167 VOLTAGE-INVERTING + + (Top View) MOTOROLA ANALOG IC DEVICE DATA MC34167 MC33167 Figure 24. Triple Output Converter Vin 24 V + 4 ILIMIT + Oscillator 1000 S Q R 2 PWM 1N5825 UVLO MUR110 VO3 1000 –12 V/200 mA + Thermal T1 Reference + VO2 + 1000 12 V/250 mA MUR110 + EA 6.8 k 1 1000 + VO1 5.0 V/3.0 A 5 3 0.1 68 k Tests Conditions Results Line Regulation 5.0 V 12 V –12 V Vin = 15 V to 30 V, IO1 = 3.0 A, IO2 = 250 mA, IO3 = 200 mA 3.0 mV = ± 0.029% 572 mV = ± 2.4% 711 mV = ± 2.9% Load Regulation 5.0 V 12 V –12 V Vin = 24 V, IO1 = 30 mA to 3.0 A, IO2 = 250 mA, IO3 = 200 mA Vin = 24 V, IO1 = 3.0 A, IO2 = 100 mA to 250 mA, IO3 = 200 mA Vin = 24 V, IO1 = 3.0 A, IO2 = 250 mA, IO3 = 75 mA to 200 mA 1.0 mV = ± 0.009% 409 mV = ±1.5% 528 mV = ± 2.0% Output Ripple 5.0 V 12 V –12 V Vin = 24 V, IO1 = 3.0 A, IO2 = 250 mA, IO3 = 200 mA 75 mVpp 20 mVpp 20 mVpp Short Circuit Current 5.0 V 12 V –12 V Vin = 24 V, RL = 0.1 Ω 6.5 A 2.7 A 2.2 A Vin = 24 V, IO1 = 3.0 A, IO2 = 250 mA, IO3 = 200 mA 84.2% Efficiency TOTAL T1 = Primary: Coilcraft M1496–A or General Magnetics Technology GMT–0223, 42 turns of #16 AWG on Magnetics Inc. 58350–A2 core. T1 = Secondary: VO2 – 69 turns of #26 AWG T1 = Secondary: VO3 – 104 turns of #28 AWG Heatsink = AAVID Engineering Inc. 5903B, or 5930B. Multiple auxiliary outputs can easily be derived by winding secondaries on the main output inductor to form a transformer. The secondaries must be connected so that the energy is delivered to the auxiliary outputs when the Switch Output turns off. During the OFF time, the voltage across the primary winding is regulated by the feedback loop, yielding a constant Volts/Turn ratio. The number of turns for any given secondary voltage can be calculated by the following equation: # TURNS(SEC) ǒ Ǔ ) VF(SEC) + VO(SEC) VO(PRI))VF(PRI) #TURNS(PRI) Note that the 12 V winding is stacked on top of the 5.0 V output. This reduces the number of secondary turns and improves lead regulation. For best auxiliary regulation, the auxiliary outputs should be less than 33% of the total output power. MOTOROLA ANALOG IC DEVICE DATA 11 MC34167 MC33167 Figure 25. Negative Input/Positive Output Regulator + 4 ILIMIT Oscillator 22 0.01 1N5825 S Q1 Q R + ǒ Ǔ) 5.05 R1 R2 0.7 2 UVLO PWM VO L D1 Thermal + R1 36 k MTP 3055E Reference + VO + 36 V/0.3 A MUR415 R1 + EA Z1 1000 2N3906 1 6.8 k 5 3 0.22 470 k R2 5.1 k 0.002 Vin –12 V 1000 + *Gate resistor RG, zener diode D3, and diode D4 are required only when Vin is greater than 20 V. Test Conditions Results Line Regulation Vin = –10 V to – 20 V, IO = 0.3 A 266 mV = ± 0.38% Load Regulation Vin = –12 V, IO = 0.03 A to 0.3 A 7.90 mV = ±1.1% Output Ripple Vin = –12 V, IO = 0.3 A 100 mVpp Efficiency Vin = –12 V, IO = 0.3 A 78.4% L = General Magnetics Technology GMT–0223, 42 turns of #16 AWG on Magnetics Inc. 58350–A2 core. Heatsink = AAVID Engineering Inc. 5903B or 5930B Figure 26. Variable Motor Speed Control with EMF Feedback Sensing + Vin 18 V 4 ILIMIT + Oscillator 1000 S Q R UVLO 2 PWM Brush Motor Thermal + Reference EA 1N5825 + 1 5.6 k 1.0 k 50 k Faster + 47 5 3 Test 12 0.1 Conditions 56 k Results Low Speed Line Regulation Vin = 12 V to 24 V 1760 RPM ±1% High Speed Line Regulation Vin = 12 V to 24 V 3260 RPM ± 6% MOTOROLA ANALOG IC DEVICE DATA MC34167 MC33167 Figure 27. Off–Line Preconverter 0.001 T1 MBR20100CT + 1000 0.001 1N5404 MC34167 Step–Down Converter + Output 1 0.001 RFI 115 VAC Filter + 220 MJE13005 MBR20100CT 0.047 1N4937 100k T2 + 1000 0.01 50 0.001 MC34167 Step–Down Converter + MC34167 Step–Down Converter + Output 2 0.001 3.3 + 100 1N4003 MBR20100CT + 1000 0.001 Output 3 T2 = Core – TDK T6 x 1.5 x 3 H5C2 T2 = 14 turns center tapped #30 AWG T2 = Heatsink = AAVID Engineering Inc. T2 = MC34167 and MJE13005 – 5903B T2 = MBR20100CT – 5925B T1 = Core and Bobbin – Coilcraft PT3595 T1 = Primary – 104 turns #26 AWG T1 = Base Drive – 3 turns #26 AWG T1 = Secondaries – 16 turns #16 AWG T1 = Total Gap – 0.002, The MC34167 can be used cost effectively in off–line applications even though it is limited to a maximum input voltage of 40 V. Figure 27 shows a simple and efficient method for converting the AC line voltage down to 24 V. This preconverter has a total power rating of 125 W with a conversion efficiency of 90%. Transformer T1 provides output isolation from the AC line and isolation between each of the secondaries. The circuit self–oscillates at 50 kHz and is controlled by the saturation characteristics of T2. Multiple MC34167 post regulators can be used to provide accurate independently regulated outputs for a distributed power system. JUNCTION-TO-AIR (°C/W) R θ JA, THERMAL RESISTANCE 80 3.5 PD(max) for TA = +50°C 70 3.0 Free Air Mounted Vertically 60 ÎÎÎÎ ÎÎÎÎ ÎÎÎÎ ÎÎÎÎ 2.0 oz. Copper L Minimum Size Pad 50 L 40 RθJA 30 0 5.0 10 15 20 25 2.5 2.0 1.5 PD, MAXIMUM POWER DISSIPATION (W) Figure 28. D2PAK Thermal Resistance and Maximum Power Dissipation versus P.C.B. Copper Length 1.0 30 L, LENGTH OF COPPER (mm) MOTOROLA ANALOG IC DEVICE DATA 13 MC34167 MC33167 Table 1. Design Equations Calculation Step–Down ton toff (Notes 1, 2) Vin Vout ) VF * Vsat * Vout Duty Cycle (Note 3) ton fosc IL avg Iout L Vripple(pp) Vout * DIL 1 Ǔ ) (ESR)2 1 ) D2IL Vin * VsatQ1 * VsatQ2 ton ǒ ǒ ) Ǔ Ǹǒ Ǔ ) ǒ )Ǔ ton toff DIL 1 1 2 foscCo R Vref 2 R1 ǒ )Ǔ t Iout on toff 1 IL avg 1 1 ton fosc ǒ )Ǔ t Iout on toff ǒ )Ǔ R Vref 2 R1 ǒ )Ǔ ton toff ton fosc toff ton fosc DIL 1 2 8foscCo ) * |Vout| VF Vin Vsat ǒ )Ǔ 1 IL avg Ǹǒ Ǔ ) VF2 * VsatQ2 ton toff ton fosc toff ) D2IL Vin * Vsat * Vout ton ǒ ) Voltage–Inverting Vout VF1 Vin VsatQ1 ǒ )Ǔ ton toff ton fosc toff ton Ipk(switch) Step–Up/Down Ǔ (ESR)2 1 ) D2IL ǒ * Ǔ ǒ ) Ǔ Ǹǒ Ǔ ) ǒ )Ǔ IL avg Vin ton toff 1 Vsat ton DIL 1 2 foscCo R Vref 2 R1 (ESR)2 1 NOTES: 1. Vsat – Switch Output source saturation voltage, refer to Figure 7. 2. VF – Output rectifier forward voltage drop. Typical value for 1N5822 Schottky barrier rectifier is 0.35 V. 3. Duty cycle is calculated at the minimum operating input voltage and must not exceed the guaranteed minimum DC(max) specification of 0.92. The following converter characteristics must be chosen: Vout – Desired output voltage. Iout – Desired output current. ∆IL – Desired peak–to–peak inductor ripple current. For maximum output current especially when the duty cycle is greater than 0.5, it is suggested that ∆IL be chosen minimum current limit threshold of 5.5 A. If the design goal is to use a minimum inductance value, let ∆IL = 2 (IL avg). This will proportionally reduce the converter’s output current capability. Vripple(pp) – Desired peak–to–peak output ripple voltage. For best performance, the ripple voltage should be kept to less than 2% of Vout. Capacitor CO should be a low equivalent series resistance (ESR) electrolytic designed for switching regulator applications. 14 MOTOROLA ANALOG IC DEVICE DATA MC34167 MC33167 OUTLINE DIMENSIONS TH SUFFIX PLASTIC PACKAGE CASE 314A–03 –T – –P – B NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH. 3. DIMENSION D DOES NOT INCLUDE INTERCONNECT BAR (DAMBAR) PROTRUSION. DIMENSION D INCLUDING PROTRUSION SHALL NOT EXCEED 0.043 (1.092) MAXIMUM. SEATING PLANE C Q E OPTIONAL CHAMFER A U F L K 1 2 3 4 5 G J 5 PL S D 5 PL 0.014 (0.356) M T P M DIM A B C D E F G J K L Q S U INCHES MIN MAX 0.572 0.613 0.390 0.415 0.170 0.180 0.025 0.038 0.048 0.055 0.570 0.585 0.067 BSC 0.015 0.025 0.730 0.745 0.320 0.365 0.140 0.153 0.210 0.260 0.468 0.505 MILLIMETERS MIN MAX 14.529 15.570 9.906 10.541 4.318 4.572 0.635 0.965 1.219 1.397 14.478 14.859 1.702 BSC 0.381 0.635 18.542 18.923 8.128 9.271 3.556 3.886 5.334 6.604 11.888 12.827 TV SUFFIX PLASTIC PACKAGE CASE 314B–05 C B –P – Q OPTIONAL CHAMFER K E A U F NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH. 3. DIMENSION D DOES NOT INCLUDE INTERCONNECT BAR (DAMBAR) PROTRUSION. DIMENSION D INCLUDING PROTRUSION SHALL NOT EXCEED 0.043 (1.092) MAXIMUM. S L W V 1 2 3 4 5 G 0.24 (0.610) J 5 PL M T H D 5 PL 0.10 (0.254) M T P M N –T – SEATING PLANE DIM A B C D E F G H J K L N Q S U V W INCHES MIN MAX 0.572 0.613 0.390 0.415 0.170 0.180 0.025 0.038 0.048 0.055 0.850 0.935 0.067 BSC 0.166 BSC 0.015 0.025 0.900 1.100 0.320 0.365 0.320 BSC 0.140 0.153 0.620 – 0.468 0.505 0.735 – 0.090 0.110 MILLIMETERS MIN MAX 14.529 15.570 9.906 10.541 4.318 4.572 0.635 0.965 1.219 1.397 21.590 23.749 1.702 BSC 4.216 BSC 0.381 0.635 22.860 27.940 8.128 9.271 8.128 BSC 3.556 3.886 – 15.748 11.888 12.827 – 18.669 2.286 2.794 Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. “Typical” parameters which may be provided in Motorola data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. Motorola does not convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury or death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall indemnify and hold Motorola and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that Motorola was negligent regarding the design or manufacture of the part. Motorola and are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal Opportunity/Affirmative Action Employer. MOTOROLA ANALOG IC DEVICE DATA 15 MC34167 MC33167 OUTLINE DIMENSIONS T SUFFIX PLASTIC PACKAGE CASE 314D–03 –T – C –Q – B SEATING PLANE NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH. 3. DIMENSION D DOES NOT INCLUDE INTERCONNECT BAR (DAMBAR) PROTRUSION. DIMENSION D INCLUDING PROTRUSION SHALL NOT EXCEED 10.92 (0.043) MAXIMUM. E U A DIM A B C D E G H J K L Q U S L 1 2 3 4 5 K S J H G D 5 PL 0.356 (0.014) M T Q INCHES MIN MAX 0.572 0.613 0.390 0.415 0.170 0.180 0.025 0.038 0.048 0.055 0.067 BSC 0.087 0.112 0.015 0.025 1.020 1.065 0.320 0.365 0.140 0.153 0.105 0.117 0.543 0.582 MILLIMETERS MIN MAX 14.529 15.570 9.906 10.541 4.572 4.318 0.965 0.635 1.397 1.219 1.702 BSC 2.845 2.210 0.635 0.381 25.908 27.051 9.271 8.128 3.886 3.556 2.972 2.667 13.792 14.783 M D2T SUFFIX PLASTIC PACKAGE CASE 936A–02 (D2PAK) OPTIONAL CHAMFER E A TERMINAL 6 –T – U S K V B H 1 2 3 4 5 M L P N D R 0.010 (0.254) M T G C NOTES: 1 DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2 CONTROLLING DIMENSION: INCH. 3 TAB CONTOUR OPTIONAL WITHIN DIMENSIONS A AND K. 4 DIMENSIONS U AND V ESTABLISH A MINIMUM MOUNTING SURFACE FOR TERMINAL 6. 5 DIMENSIONS A AND B DO NOT INCLUDE MOLD FLASH OR GATE PROTRUSIONS. MOLD FLASH AND GATE PROTRUSIONS NOT TO EXCEED 0.025 (0.635) MAXIMUM. DIM A B C D E G H K L M N P R S U V INCHES MIN MAX 0.386 0.403 0.356 0.368 0.170 0.180 0.026 0.036 0.045 0.055 0.067 BSC 0.539 0.579 0.050 REF 0.000 0.010 0.088 0.102 0.018 0.026 0.058 0.078 5 _ REF 0.116 REF 0.200 MIN 0.250 MIN MILLIMETERS MIN MAX 9.804 10.236 9.042 9.347 4.318 4.572 0.660 0.914 1.143 1.397 1.702 BSC 13.691 14.707 1.270 REF 0.000 0.254 2.235 2.591 0.457 0.660 1.473 1.981 5 _ REF 2.946 REF 5.080 MIN 6.350 MIN How to reach us: USA / EUROPE / Locations Not Listed: Motorola Literature Distribution; P.O. Box 20912; Phoenix, Arizona 85036. 1–800–441–2447 or 602–303–5454 JAPAN: Nippon Motorola Ltd.; Tatsumi–SPD–JLDC, 6F Seibu–Butsuryu–Center, 3–14–2 Tatsumi Koto–Ku, Tokyo 135, Japan. 03–81–3521–8315 MFAX: [email protected] – TOUCHTONE 602–244–6609 INTERNET: http://Design–NET.com ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, 51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298 16 ◊ *MC34167/D* MOTOROLA ANALOG IC DEVICE DATA MC34167/D