PD494 Pulse-Width-Modulation Control Circuits

Transcription

1 PD494 Pulse-Width-Modulation Control Circuits Description The PD494 is a voltage mode pulse-width-modulation switching regulator control circuit designed primarily for power supply control. The PD494 consists of a reference voltage circuit, two error amplifies, an on-chip adjustable oscillator, a dead-time control (DTC) comparator, a pulse-steering control flip-flop, and an output control circuit. The precision of voltage reference (V REF ) is improved up to ±1% through trimming and this provides a better output voltage regulation. The PD494 provides for push pull or single-ended output operation, which can be selected through the output control. The PD494 is available in standard packages of DIP-16 and SOIC-16. Feature Stable 5V Reference Voltage Trimmed to ±1% Accuracy Uncommitted output TR for 200mA sink or Source current Single-End or push-pull Operation Selected by Output Control Internal Circuitry Prohibits Double Pulse at Either Output Complete PWM Control Circuit with Variable Duty Cycle On-Chip Oscillator with Master or Slave Operation Application SMPS Back Light Inverter Charger Figure 1. Package Types of PD494 Rev

2 Pin Configuration M/P Package (SOIC-16/DIP-16) 1IN IN 1IN IN- Feedback 3 14 Ref DTC 4 13 Output Ctrl CT 5 12 V CC RT 6 11 C2 GND 7 10 E2 C1 8 9 E1 Figure 2. Pin Configuration of PD494 (Top View) Output Function Control Table Signal for Output Control V I =GND V I =V REF Output Function Single-ended or parallel output Normal push-pull operation Functional Block Diagram RT CT DTC 1IN 1IN V Error Amplifier Oscillator Dead-Time Control Comparator - PWM Comparator Pulse-Steering Flip-Flop D >CK Output Ctrl 13 8 Q Q C1 E1 C2 E2 V CC 2IN 2IN- FEEDBACK mA Reference Regulator 14 7 REF GND Figure 3. Functional Block Diagram of PD494 Rev

3 Absolute maximum rating(note 1) Parameter Symbol Value Unit Supply Voltage(Note 2) V CC 40 V Amplifier Input Voltage V I -0.3 to V CC 0.3 V Collector Output Voltage V O 40 V Collector Output Current I O 250 ma Package Thermal Impedance (Note 3) R θja M Package 73 P Package 67 /W Lead Temperature 1.6mm from case for 10 seconds 260 Storage Temperature Range T STG -65 to 150 ESD rating (Machine Model) 200 V Rev

4 Recommended Operating Conditions Parameter Symbol Min Typ Max Unit Supply Voltage V CC V Collector Output Voltage V C1,V C V Collector Output Current (Each Transistor) I C1,I C2 200 ma Amplifier Input Voltage V I 0.3 V CC -2 V Current Into Feedback Terminal I FB 0.3 ma Reference Output Current I REF 10 ma Timing Capacitor C T μf Timing Resistor R T KΩ Oscillator Frequency f osc KHz PWM Input Voltage(Pin3,4,14) V Operating Free-Air Temperature T A Note 1: Stresses greater than those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "Recommended Operating Conditions" is not implied. Exposure to "Absolute Maximum Ratings"for extended periods may affect device reliability. Note 2: All voltage values are with respect to the network ground terminal. Note 3: Maximum power dissipation is a function of T J (max), R θja and T A. The maximum allowable power dissipation at any allowable ambient temperature is P D = ( T J (max) - T A )/R θja. Operating at the absolute maximum T J of 150 can affect reliability. Rev

5 Electrical Characteristics T A =25, V CC =20V,f=10KHz unless otherwise noted Reference Section Parameter Symbol Conditions Min. Typ. Max. Unit Output Reference Voltage for PD494 V REF I REF =1mA V I REF =1mA,T A =-40 to V Line Regulation R LINE V CC =7V to 36V 2 25 mv Load Regulation R LOAD I REF =1mA to 10mA 1 15 mv Short-Circuit Output Current (Note 4) I SC V REF =0V ma Oscillator Section C T =0.001μF,R T =30 KΩ 40 Oscillator Frequency fosc C T =0.01μF,R T =12 KΩ C T =0.01μF,R T =12 KΩ, T A =-40 to KHz Frequency Change with Temperature f/ T Dead-Time Control Section C T =0.01μF,R T =12 KΩ, T A =-40 to 85 2 % Input Bias Current I BIAS V CC =15V,V PIN4 =0 to 5.25V μa Maximum Duty Cycle D(MAX) V CC =15V,V PIN4 =0V, V PIN13 =V REF 45 % Input Threshold Voltage V ITH Zero Duty Cycle Maximum Duty Cycle 0 V Error-Amplifier Section Input Offset Voltage V IO V PIN3 =2.5V 2 10 mv Input Offset Current I IO V PIN3 =2.5V na Input Bias Current I BIAS V PIN3 =2.5V μa Common-Mode Input Voltage Range V CM V CC =7V to 36V -0.3 V CC -2 V Open-Loop Voltage Gain G VO V O =3V, R L =2kΩ, V O =0.5V to 3.5V db Unity-Gain Bandwidth BW R L =2kΩ,V O =0.5V to 3.5V 650 KHz Common-Mode Rejection Ratio CMRR V O =40V,T A = db Output Sink Current (Feedback) I SINK V ID =-15mV to -5V, V(Feedback)=0.7V ma Output Soure Current(Feedback) I SOURCE V ID =15mV to 5V V(Feedback)=3.5V -2 ma Rev

6 Note 4: Duration of short circuit should not exceed one second. Electrical Characteristics(Continued) T A =25,V CC =20V,f=10KHz unless otherwise Parameter Symbol Conditions Min. Typ. Max. Unit PWM Comparator Section Input Threshold Voltage V ITH Zero duty Cycle V Input Sink Current I SINK V(Feedback)=0.7V ma Output Section Output Saturation Voltage Common Emitter Emitter Follower V CE(SAT) V E =0V,I C =200mA V CC(SAT) V CC =15V I E =-200mA V Collector Off-State Current I C(OFF) V CE =36V,V CC =36V μa Emitter Off-State Current I E(OFF) V CC =V C =36V,V E =0-100 μa Total Device Supply Current I CC V PIN6 =V REF,V CC =15V 6 10 ma Output Switching Characteristics Rise Time t R Common Emitter Common Collector ns Fall Time t F Common Emitter Common Collector ns Naming Rule PD 494 P 16 Prisemi Device 494 Series Package: M: SOIC-16 P: DIP-16 16:16 Lead Rev

7 Parameter Measurement information V CC =20V V CC Test 4 DTC Inputs 3 Feedback 12KΩ 6 RT 5 CT 0.01μF 1 1IN 2 1IN- 16 2IN 15 2IN- 8 C1 9 E1 C2 11 E Output Ctrl REF 14 GND 50KΩ 7 150Ω 4W 150Ω 4W Output 1 Output 2 Test Circuit Voltage at C1 Voltage at C2 V CC 0V V CC 0V Voltage at CT Threshold Voltage DTC 0V FEEDBACK Threshold Voltage 0.7V Duty Cycle 0% MAX 0% Voltage Waveforms Figure 4. Operational Test Circuit and Waveforms Rev

8 Parameter Measurement information(continued) V I - Amplifier Under Test FEEDBACK V REF - Other Amplifier Figure 5. Error Amplifier Characteristics 20V 68Ω 4W Each Output Circuit Output t f 90% 90% t f C L =15pF (See Note 5) 10% 10% Note 5: CL includes probe and jig capacitance Figure 6. Common-Emitter Configuration Each Output Circuit 20V 90% 90% C L =15pF (See Note 6) Output 68Ω 4W 10% 10% t f t f Note 6: C L includes probe and jig capacitance. Figure 7. Emitter-Follower Configuration Rev

9 Typical Performance Characteristics Voltage Gain(dB) f-oscillator Frequency(Hz) 100K 10K 0.1μF 0.01μF V CC =20V, T A = μF 1K 1K 10K 100K 1M RT-Timing Resistance(Ω) Figure 8. Oscillator Frequency vs. RT and CT V CC =20V, V O =3V T A = K 1M Frequency (Hz) Figure 9. Error Amplifier Small-Signal Voltage Gain vs. Frequency Rev

10 Typical Applications (V I =10V to 40V) V I () KSA1010 1mH 2A (V O =5V, I O =1A) V O 47Ω 150Ω 0.1μF 1M KΩ V CC C2 C1 Feed Back 50μF PD494 50V Output DTC GND E1 Control E IN- REF 2IN- 1IN 2IN RT CT KΩ 150Ω 5.1KΩ 50μF 10V 50μF 10V 47KΩ 0.001μF GND V I (-) Figure 10.Pulse Width Modulated Step-Down Converter 0.1Ω Rev

11 Product dimension (SOIC-16) Unit:mm(inch) 1.350(0.053) 1.750(0.069) 1.250(0.049) 0.300(0.013) (0.065) 0.510(0.020) A 20:1 B 0.250(0.010) 0.400(0.016) 1.270(0.050) 1.270(0.050) BSC 9.800(0.386) (0.402) 0 8 R0.200(0.008) R0.200(0.008) 0.170(0.007) 0.250(0.010) (0.228) 6.240(0.246) 3.800(0.150) 4.040(0.159) A 0.400(0.016) 45 B 20: (0.002) 0.250(0.010) C 0.200(0.008) SΦ1.000(0.039) Depth 0.200(0.008) C C-C 50: (0.008) 0.250(0.010) 1.000(0.039) Rev

12 Product dimension (DIP-16) Unit:mm(inch) (0.060)TYP 3.710(0.146) 4.310(0.170) 0.700(0.028) 7.320(0.288) 7.920(0.312) (0.126) 3.600(0.142) 0.360(0.014) 0.560(0.022) 2.540(0.100) TYP 0.510(0.020)MIN 3.000(0.118) 3.600(0.142) 0.204(0.008) 0.360(0.014) 8.200(0.323) 9.400(0.370) Φ3.000(0.118) Depth 0.050(0.002) 0.150(0.006) 6.200(0.244) 6.600(0.260) (0.740) (0.756) R0.750(0.030) Rev

13 IMPORTANT NOTICE and are registered trademarks of Prisemi Electronics Co., Ltd (Prisemi),Prisemi reserves the right to make changes without further notice to any products herein. Prisemi makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Prisemi 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 special, consequential or incidental damages. Typical parameters which may be provided in Prisemi 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. Prisemi does not convey any license under its patent rights nor the rights of others. The products listed in this document are designed to be used with ordinary electronic equipment or devices, Should you intend to use these products with equipment or devices which require an extremely high level of reliability and the malfunction of with would directly endanger human life (such as medical instruments, aerospace machinery, nuclear-reactor controllers, fuel controllers and other safety devices), please be sure to consult with our sales representative in advance. Website: For additional information, please contact your local Sales Representative. Copyright 2009, Prisemi Electronics is a registered trademark of Prisemi Electronics. All rights are reserved. Rev