® TOP412/414 ® TOPSwitch Family Three-terminal DC to DC PWM Switch Product Highlights Low Cost Replacement for Discrete Switchers • Up to 15 fewer components - cuts cost, increases reliability • Allows for a smaller and lighter solution under 12 mm height, all surface mount components Over 80% Efficiency in Flyback Topology • Built-in start-up and current limit reduce DC losses • Low capacitance MOSFET cuts switching losses • CMOS controller/gate driver consumes only 7 mW • 70% maximum duty cycle minimizes conduction losses VO VIN D CONTROL TOP414 C S PI-2371-120198 Simplifies Design - Reduces Time to Market • Integrated PWM Controller and high power MOSFET • Only one external capacitor needed for compensation, bypass and start-up/auto-restart functions System Level Fault Protection Features • Auto-restart and cycle by cycle current limiting functions handle both primary and secondary faults • On-chip latching thermal shutdown protects the entire system against overload Highly Versatile • Implements Buck, Boost, Flyback or Forward topology • Easily interfaces with both opto and primary feedback • Supports continuous or discontinuous mode of operation • Specified for operation down to 16 V DC input Description The TOPSwitch family implements, with only three terminals, all functions necessary for a DC to DC, converter: high voltage N-channel power MOSFET with controlled turn-on gate driver, voltage mode PWM controller with integrated 120 kHz oscillator, high voltage start-up bias circuit, bandgap derived reference, bias shunt regulator/error amplifier for loop compensation and fault protection circuitry. Compared to discrete MOSFET and controller or self oscillating (RCC) switching converter solutions, a TOPSwitch integrated circuit can reduce total cost, component count, size, weight and at the same time increase efficiency and system reliability. This device is well suited for Telecom, Cablecom and other DC to DC converter applications up to Figure 1. Typical Application. Output Power Capability1-4 MINIMUM INPUT VOLTAGE ORDER PART NUMBER TOP412G TOP414G 18 VDC 3W 4W 24 VDC 5W 6W 36 VDC 7W 9W 48 VDC 9W 12 W 60 VDC 12 W 15 W 72 VDC 15 W 18 W 90 VDC 18 W 21 W Table 1. TOP412/414 Output Power. Notes: 1. Assumes maximum junction temperature of 100 °C 2. Assumes output of 5 V and KRP of 0.4 3. Soldered to 1 sq. inch (645 mm2), 2 oz. copper clad (610 gm/mm2) 4. The continuous power capability in a given application depends on thermal environment, transformer design, efficiency required, input storage capacity, etc. 21W of output power. Internally, the lead frame of the SMD-8 package uses six of its pins to transfer heat from the chip directly to the board, eliminating the cost of a heat sink. April 1999 TOP412/414 VC 0 CONTROL DRAIN ZC SHUTDOWN/ AUTO-RESTART SHUNT REGULATOR/ ERROR AMPLIFIER + + 1 5.7 V 4.7 V INTERNAL SUPPLY ÷8 - 5.7 V POWER-UP RESET EXTERNALLY TRIGGERED SHUTDOWN + R Q S Q - THERMAL SHUTDOWN IFB VI LIMIT CONTROLLED TURN-ON GATE DRIVER OSCILLATOR DMAX CLOCK SAW - S Q + R Q LEADING EDGE BLANKING PWM COMPARATOR MINIMUM ON-TIME DELAY RE SOURCE PI-1746-011796 Figure 2. Functional Block Diagram. Pin Functional Description DRAIN Pin: Output MOSFET drain connection. Provides internal bias current during start-up operation via an internal switched highvoltage current source. Internal current sense point. CONTROL Pin: Error amplifier and feedback current input pin for duty cycle control. Internal shunt regulator connection to provide internal bias current during normal operation. Trigger input for latching shutdown. It is also used as the supply bypass and auto-restart/ compensation capacitor connection point. SOURCE 1 8 SOURCE (HV RTN) SOURCE 2 7 SOURCE (HV RTN) SOURCE 3 6 SOURCE (HV RTN) CONTROL 4 5 DRAIN G Package (SMD-8) SOURCE Pin: Output MOSFET source connection. Primary-side circuit common, power return, and reference point. 2 A 4/99 PI-2208-120798 Figure 3. Pin Configuration. TOP412/414 TOPSwitch Family Functional Description During normal operation, the internal output MOSFET duty cycle linearly decreases with increasing CONTROL pin current as shown in Figure 4. To implement all the required control, bias, and protection functions, the DRAIN and CONTROL pins each perform several functions as described below. Refer to Figure 2 for a block diagram and Figure 6 for timing and voltage waveforms of the TOPSwitch integrated circuit. Control Voltage Supply CONTROL pin voltage VC is the supply or bias voltage for the controller and driver circuitry. An external bypass capacitor closely connected between the CONTROL and SOURCE pins is required to supply the gate drive current. The total amount of capacitance connected to this pin (CT) also sets the auto-restart timing as well as control loop compensation. VC is regulated in either of two modes of operation. Hysteretic regulation is used for initial start-up and overload operation. Shunt regulation is used to separate the duty cycle error signal from the control circuit supply current. During start-up, VC current is supplied from a high-voltage switched current source connected internally between the DRAIN and CONTROL pins. The current source provides sufficient current to supply the control circuitry as well as charge the total external capacitance (CT). Auto-restart IB DMAX Slope = PWM Gain -16%/mA Duty Cycle (%) TOPSwitch is a self biased and protected linear control currentto-duty cycle converter with an open drain output. High efficiency is achieved through the use of CMOS and integration of the maximum number of functions possible. CMOS significantly reduces bias currents as compared to bipolar or discrete solutions. Integration eliminates external power resistors used for current sensing and/or supplying initial start-up bias current. DMIN ICD1 2.5 6.5 45 IC (mA) PI-1691-112895 Figure 4. Relationship of Duty Cycle to CONTROL Pin Current. VC 5.7 V 4.7 V IC Charging CT 0 DRAIN VIN Off 0 Switching (a) IC Charging CT VC ICD2 Discharging CT ICD1 Discharging CT 5.7 V 4.7 V 8 Cycles 0 95% DRAIN VIN Off 5% Off Off 0 Switching Switching (b) CT is the total external capacitance connected to the CONTROL pin PI-1124A-060694 Figure 5. Start-up Waveforms for (a) Normal Operation and (b) Auto-restart. A 4/99 3 TOP412/414 TOPSwitch Family Functional Description (cont.) The first time VC reaches the upper threshold, the high-voltage current source is turned off and the PWM modulator and output transistor are activated, as shown in Figure 5(a). During normal operation (when the output voltage is regulated) feedback control current supplies the VC supply current. The shunt regulator keeps VC at typically 5.7 V by shunting CONTROL pin feedback current exceeding the required DC supply current through the PWM error signal sense resistor RE. The low dynamic impedance of this pin (ZC) sets the gain of the error amplifier when used in a primary feedback configuration. The dynamic impedance of the CONTROL pin together with the external resistance and capacitance determines the control loop compensation of the power system. If the CONTROL pins total external capacitance (CT) should discharge to the lower threshold, the output MOSFET is turned off and the control circuit is placed in a low-current standby mode. The high-voltage current source is turned on and charges the external capacitance again. Charging current is shown with a negative polarity and discharging current is shown with a positive polarity in Figure 6. The hysteretic auto-restart comparator keeps VC within a window of typically 4.7 to 5.7 V by turning the high-voltage current source on and off as shown in Figure 5(b). The auto-restart circuit has a divide-by-8 counter which prevents the output MOSFET from turning on again until eight discharge-charge cycles have elapsed. The counter effectively limits TOPSwitch power dissipation by reducing the auto-restart duty cycle to typically 5%. Autorestart continues to cycle until output voltage regulation is again achieved. Bandgap Reference All critical TOPSwitch internal voltages are derived from a temperature-compensated bandgap reference. This reference is also used to generate a temperature-compensated current source which is trimmed to accurately set the oscillator frequency and MOSFET gate drive current. Oscillator The internal oscillator linearly charges and discharges the internal capacitance between two voltage levels to create a sawtooth waveform for the pulse width modulator. The oscillator sets the pulse width modulator/current limit latch at the beginning of each cycle. The nominal frequency of 120 kHz was chosen to minimize EMI and maximize efficiency in power supply applications. Trimming of the current reference improves the frequency accuracy. Pulse Width Modulator The pulse width modulator implements a voltage-mode control loop by driving the output MOSFET with a duty cycle inversely proportional to the current flowing into the CONTROL pin. The error signal across RE is filtered by an RC network with a 4 A 4/99 typical corner frequency of 7 kHz to reduce the effect of switching noise. The filtered error signal is compared with the internal oscillator sawtooth waveform to generate the duty cycle waveform. As the control current increases, the duty cycle decreases. A clock signal from the oscillator sets a latch which turns on the output MOSFET. The pulse width modulator resets the latch, turning off the output MOSFET. The maximum duty cycle is set by the symmetry of the internal oscillator. The modulator has a minimum ON-time to keep the current consumption of the TOPSwitch independent of the error signal. Note that a minimum current must be driven into the CONTROL pin before the duty cycle begins to change. Gate Driver The gate driver is designed to turn the output MOSFET on at a controlled rate to minimize common-mode EMI. The gate drive current is trimmed for improved accuracy. Error Amplifier The shunt regulator can also perform the function of an error amplifier in primary feedback applications. The shunt regulator voltage is accurately derived from the temperature compensated bandgap reference. The gain of the error amplifier is set by the CONTROL pin dynamic impedance. The CONTROL pin clamps external circuit signals to the VC voltage level. The CONTROL pin current in excess of the supply current is separated by the shunt regulator and flows through RE as the error signal. Cycle-By-Cycle Current Limit The cycle by cycle peak drain current limit circuit uses the output MOSFET ON-resistance as a sense resistor. A current limit comparator compares the output MOSFET ON-state drain-source voltage, VDS(ON), with a threshold voltage. High drain current causes VDS(ON) to exceed the threshold voltage and turns the output MOSFET off until the start of the next clock cycle. The current limit comparator threshold voltage is temperature compensated to minimize variation of the effective peak current limit due to temperature related changes in output MOSFET RDS(ON). The leading edge blanking circuit inhibits the current limit comparator for a short time after the output MOSFET is turned on. The leading edge blanking time has been set so that current spikes caused by primary-side capacitances and secondary-side rectifier reverse recovery time will not cause premature termination of the switching pulse. Shutdown/Auto-restart To minimize TOPSwitch power dissipation, the shutdown/ auto-restart circuit turns the power supply on and off at a duty cycle of typically 5% if an out of regulation condition persists. Loss of regulation interrupts the external current into the TOP412/414 VIN VIN DRAIN 0 VOUT 0 IOUT 0 1 8 2 1 2 ••• VC 8 1 ••• VC(reset) 0 45 mA 1 IC 2 8 1 ••• 0 1 2 8 1 ••• 2 3 4 1 PI-1119-110194 Figure 6. Typical Waveforms for (1) Normal Operation, (2) Auto-restart, (3) Latching Shutdown, and (4) Power Down Reset. CONTROL pin. VC regulation changes from shunt mode to the hysteretic auto-restart mode described above. When the fault condition is removed, the power supply output becomes regulated, VC regulation returns to shunt mode, and normal operation of the power supply resumes. Latching Shutdown The output overvoltage protection latch is activated by a highcurrent pulse into the CONTROL pin. When set, the latch turns off the TOPSwitch output. Activating the power-up reset circuit by removing and restoring input power, or momentarily pulling the CONTROL pin below the power-up reset threshold resets the latch and allows TOPSwitch to resume normal power supply operation. VC is regulated in hysteretic mode when the power supply is latched off. Over-Temperature Protection Temperature protection is provided by a precision analog circuit that turns the output MOSFET off when the junction temperature exceeds the thermal shutdown temperature (typically 145 °C). Activating the power-up reset circuit by removing and restoring input power or momentarily pulling the CONTROL pin below the power-up reset threshold resets the latch and allows TOPSwitch to resume normal power supply operation. VC is regulated in hysteretic mode when the power supply is latched off. High-voltage Bias Current Source This current source biases TOPSwitch from the DRAIN pin and charges the CONTROL pin external capacitance (CT) during start-up or hysteretic operation. Hysteretic operation occurs during auto-restart and latched shutdown. The current source is switched on and off with an effective duty cycle of approximately 35%. This duty cycle is determined by the ratio of CONTROL pin charge (IC) and discharge currents (ICD1 and ICD2). This current source is turned off during normal operation when the output MOSFET is switching. A 4/99 5 TOP412/414 General Circuit Operation In the example circuit, C1 provides local decoupling of the DC input. This is required when the DC input source is distant from this converter. A shottky diode (D2) with low voltage drop provides secondary rectification and does not require additional heat sinking (PC-board provides adequate heat sinking when used with DPAK diode package). Tantalum capacitors (C3,C4) provide low profile and small outline for secondary capacitance (electrolytic capacitors can also be used as replacement). Inductor L1 filters high frequency switching noise forming a π filter with the output capacitors (C3-C6). The control loop gain is set by resistor R2 and the stability is influenced by R1, C3 ,C4, C5 and C6. Resistors R3 and R4 set the DC regulation point and shunt regulator U3 along with bypass capacitor C8, provide the drive for the optocoupler U2. Any remaining switching noise in the system is filtered by ceramic capacitor C9. Figure 7 shows a typical DC-DC converter application using the TOP414G. This supply delivers 5 V at 2 A and works over a wide input range from 36-72 VDC. The power supply operates at an ambient temperature of 0-50 °C. In order to achieve the highest possible efficiency and smallest possible circuit board area, the primary and secondary current waveform is shaped to have the lowest possible RMS and ripple current. This is achieved by running very continuous and utilizing the maximum duty cycle available. For the example shown, the maximum component height is 12 mm. The EFD-20 transformer core was chosen to match this maximum component height. The TOP414G has a high current limit, which means that the EF20 core will saturate during startup, until regulation is achieved. This is acceptable with the TOP414G and does not cause device stress (provided the maximum drain voltage is below 250 V peak and provided a Zener is used for clamping). A Zener diode clamp circuit (VR1 and D1) is used in order to clamp the leakage inductance spike to a fixed maximum voltage (an RCD, resistor capacitor diode, clamp circuit would not be acceptable for this application). D2 MBRD620CT 9, 10 1 VR1 ZGL41-100 6, 7 36-72 V DC Input C1 10 µF 100 V D1 MURS120T3 2 S C4 330 µF 10 V C6 330 µF 6.3 V C5 330 µF 6.3 V C9 2.2 µF 5V 2.0 A RTN 5 C7 100 nF TOPSwitch CONTROL C3 330 µF 10 V L1 3.3 µH D3 1N4148 U1 TOP414G D Capacitor C2 and resistor R1 form part of the CONTROL pin feedback circuit. Capacitor CX is used solely to decouple high frequency noise on the control pin. T1 U2 PC317A 4 R2 150 Ω C CX 100 nF R1 15 Ω C2 47 µF R3 10k U3 TL431ACD C8 100 nF R4 10k PI-2220-120998 Figure 7. Schematic Diagram of a 5 V, 10 W Isolated DC to DC Converter. 6 A 4/99 TOP412/414 Key Application Issues Use a Kelvin connection to the SOURCE pin for the CONTROL pin bypass capacitor. Use single point grounding techniques at the SOURCE pin as shown in Figure 8. Use a ceramic high frequency decoupling capacitor to bypass noise transients which might appear on the CONTROL pin. The TOP412 and TOP414 have an over current latching shutdown feature. Failure to use a high frequency decoupling capacitor may allow incidental noise to accidentally trigger this feature. Limit peak voltage and ringing on the DRAIN voltage at turnoff to a safe value. Use a Zener or TVS Zener diode to clamp the DRAIN voltage. Do not plug the TOPSwitch device into a “hot” IC socket during test. External CONTROL pin capacitance may deliver a surge current sufficient to trigger the shutdown latch which turns the TOPSwitch off. Under some conditions, externally provided bias or supply current driven into the CONTROL pin can hold the TOPSwitch in one of the 8 auto-restart cycles indefinitely and prevent starting. Shorting the CONTROL pin to the SOURCE pin will reset the TOPSwitch. To avoid this problem when doing bench evaluations, it is recommended that the VC power supply be turned on before the DRAIN voltage is applied. CONTROL pin currents during auto-restart operation are much lower at low input voltages (< 20 V) which increases the autorestart cycle period (see the IC vs. Drain Voltage Characteristic curve). In some cases, minimum loading may be necessary to keep a lightly loaded or unloaded output voltage within the desired range due to the minimum ON-time. For additional applications information regarding the TOPSwitch family, refer to Web site, www.powerint.com. G PACKAGE Bias/Feedback Return SOURCE SOURCE High Voltage Return Bias/Feedback Input CONTROL Kelvin-connected auto-restart/bypass capacitor C5 and/or compensation network DRAIN CONTROL pin transient decoupling capacitor TOP VIEW PI-2210-102798 Figure 8. Recommended TOPSwitch Layout. A 4/99 7 TOP412/414 ABSOLUTE MAXIMUM RATINGS(1) DRAIN Voltage ............................................ -0.3 to 350 V CONTROL Voltage ..................................... - 0.3 V to 9 V Storage Temperature ..................................... -65 to 150 °C Notes: 1. All voltages referenced to SOURCE, TA = 25 °C. 2. Normally limited by internal circuitry. 3. 1/16" from case for 5 seconds. Operating Junction Temperature(2) ................ -40 to 150 °C Lead Temperature(3) ................................................ 260 °C THERMAL IMPEDANCE Thermal Impedance (θJA) ................................... 15 °C/W(1) 1. Soldered to 1 sq. inch (645 mm2), 2 oz. (610 gm/m2) copper clad. Thermal Impedance (θJC) ..................................... 11 °C/W Conditions Specification Symbol (Unless Otherwise Specified) See Figure 11 SOURCE = 0 V TJ = -40 to 125 °C Min Typ Max Units CONTROL FUNCTIONS Output Frequency fOSC IC = 4 mA, Tj = 25 °C 108 120 132 kHz Maximum Duty Cycle DCMAX IC = ICD1+ 0.5 mA, See Figure 9 64 67 70 % Minimum Duty Cycle TOP412 1.0 1.8 3.0 DCMIN TOP414 1.3 2.1 3.3 -21 -16 -11 IC = 4 mA, TJ = 25 °C PWM Gain IB Dynamic Impedance ZC 8 A 4/99 %/mA See Figure 4 IC = 4 mA, TJ = 25 °C %/mA/°C -0.05 See Note A External Bias Current Temperature Drift % See Figure 4 PWM Gain Temperature Drift Dynamic Impedance IC = 10 mA, See Figure 9 1.5 2.5 4 mA 10 15 22 Ω See Figure 10 0.18 %/°C TOP412/414 Conditions Specification Symbol (Unless Otherwise Specified) See Figure 11 SOURCE = 0 V TJ = -40 to 125 °C Min Typ Max VC = 0 V -2.4 -1.9 -1.2 VC = 5 V -2.0 -1.5 -0.8 Units SHUTDOWN/AUTO-RESTART CONTROL Pin Charging Current IC Charging Current Temperature Drift TJ = 25 °C mA See Note A 0.4 %/°C S1 open 5.7 V UV Lockout Threshold Voltage S1 open 4.7 V Auto-restart Hysteresis Voltage S1 open 1.0 V Auto-restart Duty Cycle S1 open 5 Auto-restart Frequency S1 open 1.2 Auto-restart Threshold Voltage VC(AR) 0.6 8 % Hz CIRCUIT PROTECTION TOP412 Self-protection Current Limit ILIMIT di/dt = 400 mA/µs, TJ = 25 °C 2.00 2.90 A TOP414 di/dt = 600 mA/µs, TJ = 25 °C 2.95 4.25 Leading Edge Blanking Time tLEB IC = 4 mA 150 ns Current Limit Delay tILD IC = 4 mA 100 ns °C Thermal Shutdown Temperature IC = 4 mA 125 145 Latched Shutdown Trigger Current ISD See Figure 10 25 45 75 mA Power-up Reset Threshold Voltage VC(RESET) S2 open 2.0 3.3 4.2 V A 4/99 9 TOP412/414 Conditions Specification Symbol (Unless Otherwise Specified) See Figure 11 SOURCE = 0 V TJ = -40 to 125 °C Min Typ Max Units OUTPUT ON-State Resistance RDS(ON) OFF-State Current IDSS Breakdown Voltage BVDSS TOP412 TJ = 25 °C 2.6 3.0 ID = 270 mA TJ = 100 °C 4.2 5.0 TOP414 TJ = 25 °C 1.7 2.0 ID = 400 mA TJ = 100 °C 2.8 3.3 Device in Latched Shutdown 500 IC = 4 mA, VDS = 280 V, TA = 125 °C Ω µA Device in Latched Shutdown IC = 4 mA, ID = 500 µA, TA = 25 °C V 350 Measured With Rise Time tR Fall Time tF Figure 7 Schematic 100 ns 50 ns Measured With Figure 7 Schematic SUPPLY DRAIN Supply Voltage Shunt Regulator Voltage VC(SHUNT) See Note B 36 IC = 4 mA 5.5 Shunt Regulator Temperature Drift CONTROL Supply/ Discharge Current A 4/99 5.8 6.1 ±50 ICD1 ICD2 10 V Output MOSFET Enabled ppm/°C TOP412 0.6 1.2 1.6 TOP414 0.8 1.4 1.8 0.5 0.8 1.1 Output MOSFET Disabled V mA TOP412/414 Conditions Specification Symbol (Unless Otherwise Specified) See Figure 11 VS2 = 16 V R1 = 0 Ω SOURCE = 0 V TJ = -40 to 125 °C Min Typ Max Units LOW INPUT VOLTAGE OPERATION (See Note C) DRAIN Supply Voltage CONTROL Pin Charging Current See Note D TJ = 25 °C Volts 16 VC = 0 V -2.30 -1.65 -1.00 mA VC = 5 V -1.20 -0.64 -0.28 mA 8 % Auto-restart Duty Cycle S1/Open 4 Auto-restart Frequency S1/Open 0.85 Hz NOTES: A. For specifications with negative values, a negative temperature coefficient corresponds to an increase in magnitude with increasing temperature, and a positive temperature coefficient corresponds to a decrease in magnitude with increasing temperature. B. It is possible to start up and operate TOPSwitch at DRAIN voltages well below 36 V. Refer to the "Low Input Voltage" Specification section for details. C. This section specifies only parameters affected by low input voltage operation (Drain Voltages less than 36 V). All other parameters remain unchanged. D. For low input voltage applications, the primary peak current could be set to a lower value than the current limit to increase efficiency. Refer to the Output Characteristics graph (Drain Current vs. Drain Voltage). The voltage across the transformer primary during the ON time is the difference between the input voltage and the drain voltage (VDS(ON)). For example, if the input voltage is 16 VDC and a TOP414 (2.95 A minimum current limit) is used at a primary peak current of 1A. Then the (VDS(ON)) is 3 V at 100 °C and the energizing voltage across the transformer primary is 13 V. A 4/99 11 TOP412/414 TYPICAL CONTROL PIN I-V CHARACTERISTIC 90% DRAIN VOLTAGE t DC = 1 t2 10% 0V PI-1215-091794 PI-1216-091794 t1 HV 90% CONTROL Pin Current (mA) 120 t2 100 80 Latched Shutdown Trigger Current (45 mA) 60 40 Dynamic 1 = Impedance Slope 20 0 Figure 9. TOPSwitch Duty Cycle Measurement. 0 2 4 6 8 10 CONTROL Pin Voltage (V) Figure 10. TOPSwitch CONTROL Pin I-V Characteristic. R1 470 Ω 5W D CONTROL TOPSwitch S2 R2 470 Ω C S1 S C1 0.1 µF C2 47 µF VS1 0-50 V VS2 40 V NOTES: 1. This test circuit is not applicable for current limit or output characteristic measurements. 2. For P package, short all SOURCE and SOURCE (HV RTN) pins together. PI-2212-073098 Figure 11. TOPSwitch General Test Circuit. 12 A 4/99 TOP412/414 BENCH TEST PRECAUTIONS FOR EVALUATION OF ELECTRICAL CHARACTERISTICS The following precautions should be followed when testing TOPSwitch by itself outside of a power supply. The schematic shown in Figure 11 is suggested for laboratory testing of TOPSwitch. When the DRAIN supply is turned on, the part will be in the auto-restart mode. The CONTROL pin voltage will be oscillating at a low frequency from 4.7 to 5.7 V and the DRAIN is turned on every eighth cycle of the CONTROL pin oscillation. If the CONTROL pin power supply is turned on while in this autorestart mode, there is only a 12.5% chance that the CONTROL pin oscillation will be in the correct state (DRAIN active state) so that the continuous DRAIN voltage waveform may be observed. It is recommended that the VC power supply be turned on first and the DRAIN power supply second if continuous drain voltage waveforms are to be observed. The 12.5% chance of being in the correct state is due to the 8:1 counter. Typical Performance Characteristics BREAKDOWN vs. TEMPERATURE 1.0 PI-1123A-060794 1.2 Output Frequency (Normalized to 25 °C) PI-176B-051391 1.0 0.8 0.6 0.4 0.2 0.9 0 -50 -25 0 25 50 75 100 125 150 -50 -25 Junction Temperature (°C) 50 75 100 125 150 0.8 0.6 0.4 0.2 0 IC vs. DRAIN VOLTAGE 2 CONTROL Pin Charging Current (mA) PI-1125-041494 Current Limit (Normalized to 25 °C) 1.0 25 Junction Temperature (°C) CURRENT LIMIT vs. TEMPERATURE 1.2 0 PI-1145-103194 Breakdown Voltage (V) (Normalized to 25 °C) 1.1 FREQUENCY vs. TEMPERATURE VC = 5 V 1.6 1.2 0.8 0.4 0 -50 -25 0 25 50 75 100 125 150 Junction Temperature (°C) 0 20 40 60 80 100 Drain Voltage (V) A 4/99 13 TOP412/414 Typical Performance Characteristics (cont.) OUTPUT CHARACTERISTICS Drain Current (A) DRAIN Capacitance (pF) TCASE = 25 °C TCASE = 100 °C 4 1000 PI-2214-120198 5 3 2 Scaling Factors: TOP414 1.00 TOP412 0.67 1 Scaling Factors: TOP414 1.00 TOP412 0.67 100 10 0 0 2 4 6 10 8 0 80 Drain Voltage (V) PI-2218-120195 100 Power (mW) Scaling Factors: TOP414 1.00 TOP412 0.67 50 0 0 80 160 240 DRAIN Voltage (V) A 4/99 160 240 DRAIN Voltage (V) DRAIN CAPACITANCE POWER 14 PI-2216-120198 COSS vs. DRAIN VOLTAGE 320 320 TOP412/414 SMD-8 Heat Sink is 2 oz. Copper As Big As Possible D S .004 (.10) -E- 8 inches mm A B C G H J1 J2 J3 J4 K L M P α 0.370-0.385 0.245-0.255 0.125-0.135 0.004-0.012 0.036-0.044 0.060 (NOM) 0.048-0.053 0.032-0.037 0.007-0.011 0.010-0.012 0.100 BSC 0.030 (MIN) 0.372-0.388 0-8° 9.40-9.78 6.22-6.48 3.18-3.43 0.10-0.30 0.91-1.12 1.52 (NOM) 1.22-1.35 0.81-0.94 0.18-0.28 0.25-0.30 2.54 BSC 0.76 (MIN) 9.45-9.86 0-8° 5 1 E S .010 (.25) P B .420 .046 .060 .080 .086 .186 .286 -D- A M .060 .046 Pin 1 4 L Solder Pad Dimensions J1 C K -F.004 (.10) J3 G08A DIM J4 J2 .010 (.25) M A S α G H Notes: 1. Package dimensions conform to JEDEC specification MS-001-AB (issue B, 7/85) except for lead shape and size. 2. Controlling dimensions are inches. 3. Dimensions shown do not include mold flash or other protrusions. Mold flash or protrusions shall not exceed .006 (.15) on any side. 4. D, E and F are reference datums on the molded body. PI-2077-042601 A 4/99 15 TOP412/414 For the latest updates, visit our Web site: www.powerint.com Power Integrations reserves the right to make changes to its products at any time to improve reliability or manufacturability. Power Integrations does not assume any liability arising from the use of any device or circuit described herein, nor does it convey any license under its patent rights or the rights of others. The PI Logo, TOPSwitch, TinySwitch and EcoSmart are registered trademarks of Power Integrations, Inc. ©Copyright 2001, Power Integrations, Inc. WORLD HEADQUARTERS AMERICAS Power Integrations, Inc. 5245 Hellyer Avenue San Jose, CA 95138 USA Main: +1 408-414-9200 Customer Service: Phone: +1 408-414-9665 Fax: +1 408-414-9765 e-mail: [email protected] EUROPE & AFRICA Power Integrations (Europe) Ltd. Centennial Court Easthampstead Road Bracknell Berkshire, RG12 1YQ United Kingdom Phone: +44-1344-462-300 Fax: +44-1344-311-732 e-mail: [email protected] TAIWAN Power Integrations International Holdings, Inc. 17F-3, No. 510 Chung Hsiao E. Rd., Sec. 5, Taipei, Taiwan 110, R.O.C. Phone: +886-2-2727-1221 Fax: +886-2-2727-1223 e-mail: [email protected] CHINA Power Integrations International Holdings, Inc. Rm# 1705, Bao Hua Bldg. 1016 Hua Qiang Bei Lu Shenzhen, Guangdong 518031 China Phone: +86-755-367-5143 Fax: +86-755-377-9610 e-mail: [email protected] KOREA Power Integrations International Holdings, Inc. Rm# 402, Handuk Building 649-4 Yeoksam-Dong, Kangnam-Gu, Seoul, Korea Phone: +82-2-568-7520 Fax: +82-2-568-7474 e-mail: [email protected] JAPAN Power Integrations, K.K. Keihin-Tatemono 1st Bldg. 12-20 Shin-Yokohama 2-Chome Kohoku-ku, Yokohama-shi Kanagawa 222-0033, Japan Phone: +81-45-471-1021 Fax: +81-45-471-3717 e-mail: [email protected] INDIA (Technical Support) Innovatech #1, 8th Main Road Vasanthnagar Bangalore, India 560052 Phone: +91-80-226-6023 Fax: +91-80-228-9727 e-mail: [email protected] APPLICATIONS HOTLINE World Wide +1-408-414-9660 16 A 4/99 APPLICATIONS FAX World Wide +1-408-414-9760