IP1524B SERIES SEME LAB REGULATING PULSE WIDTH MODULATORS TOP VIEW INV. INPUT 1 16 VREF N. I. INPUT 2 15 VIN OSC. OUTPUT 3 14 EB +C.L. SENSE 4 13 CB –C.L. SENSE 5 12 CA RT 6 11 EA CT 7 10 SHUTDOWN GROUND 8 9 FEATURES COMPENSATION J Package – 16 Pin Ceramic DIP N Package – 16 Pin Plastic DIP D Package – 16 Pin Plastic (300) SOIC • • • • • • • • • • • • Pin Compatible with IP1524 Series 7 to 40 volt operation 5 volt reference trimmed to ±1% Undervoltage lockout Excellent external sync capability Wide current limit common mode range +5 Volt error amplifier common mode PWM data latch Full double-pulse suppression logic 50ns shutdown function Dual 200mA, 60V output transistors Fully specified over temperature Order Information Part Number IP1524B IP2524B IP3524B J–Pack 16 Pin ✔ ✔ ✔ N–Pack 16 Pin D–16 16 Pin ✔ ✔ ✔ ✔ Temp. Range -55 to +125°C -25 to +85°C 0 to +70°C Note: To order, add the package identifier to the part number. eg. IP1524BJ IP3524BD–16 ABSOLUTE MAXIMUM RATINGS (Tcase = 25°C unless otherwise stated) +VIN Input Voltage +40V Collector Voltage +60V Logic Inputs –0.3 to +5.5V Current Limit Sense Inputs –0.3 to +VIN Oscillator Charging Current 5mA PD Power Dissipation TA = 25°C Derate @ TA > 50°C 1W 10mW/°C PD Power Dissipation TC = 25°C Derate @ TC > 25°C 2W 16mW/°C TJ Operating Junction Temperature TSTG Storage Temperature Range TL Lead Temperature Semelab plc. See Ordering Information –65 to +150°C (soldering, 10 seconds) Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. +300°C Prelim. 3/95 IP1524B SERIES SEME LAB DESCRIPTION The IP1524B is a pulse width modulator for switching power supplies which features improved performance over industry standards like the SG1524. A direct pin-for-pin replacement for the earlier device, it combines advanced processing techniques and circuit design to provide improved reference accuracy/ and extended common mode range at the error amplifier and current limit inputs. A DC-coupled flip-flop eliminates triggering and glitch problems, and a PWM data latch prevents edge oscillations. The circuit incorporates true digital shutdown for high speed response, while an undervoltage lockout circuit prevents spurious outputs when the supply voltage is too low for stable operation. Full double-pulse suppression logic insures alternating output pulses when the shutdown pin is used for pulse-by-pulse current limiting. BLOCK DIAGRAM VREF 16 15 +VIN UNDER VOLTAGE LOCKOUT REFERENCE REGULATOR 8 GND TO INTERNAL CIRCUITRY RT CT OSC. 7 12 3 6 CA OSCILLATOR S 11 Q EA T R INV. INPUT N.I. INPUT +C.L. SENSE –C.L. SENSE 2 Q 13 TOGGLE F/F CB D PWM 14 Q ERROR EB PWM LATCH 4 5 MEMORY F/F S Q 1 Q C.L. 10 9 SHUTDOWN COMPENSATION RECOMMENDED OPERATING CONDITIONS VIN Input Voltage +7 to +40V Collector Voltage 0 to +60V Error Amp Common Mode Range +2.3 to VREF Current Limit Sense Common Mode Range Output Current 0 to VIN – 2.5V (each transistor) Reference Load Current 0 to 200mA 0 to 20mA Oscillator Charging Current 25µA to 1.8mA Oscillator Frequency Range 50Hz to 500kHz RT Oscillator Timing Resistor 2kΩ to 150kΩ CT Oscillator Timing Capacitor 1nF to 0.1µF Operating Ambient Temperature Range Semelab plc. IP1524B IP2524B IP3524B Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. –55 to +125°C –25 to +85°C 0 to +70°C Prelim. 3/95 IP1524B SERIES SEME LAB ELECTRICAL CHARACTERISTICS (TJ = Over Operating Temperature Range unless otherwise stated) IP1524B IP2524B Min. Typ. Max. Test Conditions 1 Parameter Min. IP3524B Typ. Max. Units TURN–ON CHARACTERISTICS VIN Undervoltage Threshold VIN Rising 4.3 5.2 6.5 4.3 5.2 6.5 Turn–on Hysteresis 0.1 0.3 0.6 0.1 0.3 0.6 7 10 7 10 5.00 5.05 4.90 5.00 5.10 5.10 4.85 VIN = 7 to 40V Operating Current V mA REFERENCE SECTION TJ = 25°C Output Voltage VIN = 7 to 40V 4.95 IL = 0 to 20mA 4.90 5.15 Line Regulation VIN = 7 to 40V 1 10 1 15 Load Regulation IL = 0 to 20mA 5 15 5 25 40 75 40 75 70 120 70 120 1 10 43 45 0.1 Temperature Stability Short Circuit Current VREF = 0 Long Term Stability TJ = 25°C 25 OSCILLATOR SECTION Initial Accuracy TJ = 25°C Voltage Stability VIN = 7 to 40V 25 V mV mA mV 1 khr 2 41 Temperature Stability 39 43 47 1 0.1 1 1 2 1 2 80 140 80 140 kHz % Minimum Frequency RT = 150kΩ CT = 0.1µF Maximum Frequency RT = 2kΩ CT = 470pF 400 700 400 700 kHz Clock Amplitude Output, Pin 3 CT = 0.01µF 3.0 4.0 3.0 4.0 V Clock Pulse Width Output, Pin 3 CT = 0.01µF 0.4 0.5 1.2 0.4 0.5 1.2 Sawtooth Peak Voltage CT = 0.01µF 3.7 4.0 3.7 4.0 Sawtooth Valley Voltage CT = 0.01µF 1 1.1 1 1.1 Sawtooth Valley T.C. TJ = 25°C 0.6 0.6 µs V mV/°C -1 -1 Hz ERROR AMP SECTION Input Offset Voltage VCM = 2.3 to VREF 0.1 5 2 10 Input Bias Current VCM = 2.3 to VREF 1 5 1 10 Input Offset Current VCM = 2.3 to VREF 0.1 1 0.1 1 mV µA NOTES 1. Test Conditions unless otherwise stated: VIN = 20V , IREF = 0. TJ = –55 to +125°C for IP1524B TJ = –25 to +85°C for IP2524B for IP3524B TJ = 0 to +70°C Semelab plc. 2. RT = 2.7KΩ , CT = 0.01µF unless otherwise stated. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Prelim. 3/95 IP1524B SERIES SEME LAB ELECTRICAL CHARACTERISTICS (TJ = Over Operating Temperature Range unless otherwise stated) IP1524B IP2524B Min. Typ. Max. Test Conditions 1 Parameter Min. IP3524B Typ. Max. Units ERROR AMP SECTION (cont.) DC Open Loop Gain ∆VO = 1 to 3V Common Mode Rejection RL ≥ 10MΩ 60 75 60 75 VCM = 2.3 to VREF 70 90 70 90 Supply Voltage Rejection VIN = 7 to 40V 76 120 76 120 Output Low Level ISINK = 100µA Output High Level ISOURCE = 100µA Gain Bandwidth Product TJ = 25°C 0.2 0.2 0.5 3.8 4.2 3.8 4.2 1 2 1 2 dB 0.5 V MHz PWM COMPARATOR Minimum Duty Cycle VPIN1 – VPIN2 ≥ 150mV Maximum Duty Cycle VPIN2 – VPIN1 ≥ 150mV 0 0 45 49 180 200 220 -1 -10 % 45 49 180 200 220 mV -1 -10 µA CURRENT LIMIT AMPLIFIER VCM = 0 to 17.5V Sense Voltage VIN = 7 to 40V VCM = 0 to 17.5V Input Bias Current VIN = 7 to 40V SHUTDOWN INPUT VSHUTDOWN = 5V High Input Current V 2.0 2.0 High Input Voltage 0.1 0.1 1 0.6 Low Input Voltage Pin 10 to output Shutdown Delay TJ = 25°C 1 mA 0.6 V ns 50 50 OUTPUT SECTION (each transistor) Collector Leakage Current Collector Saturation Voltage Emitter Output Voltage VCE = 60V 0.1 20 0.1 20 IC = 20mA 0.2 0.4 0.2 0.4 IC = 200mA 1.0 2.2 1.0 2.2 IE = 50mA 17 19 17 19 IE = 200mA 16.5 18 16.5 18 Emitter Voltage Rise Time RE = 2kΩ TJ = 25°C 0.2 0.4 0.2 Collector Voltage Fall Time RC = 2kΩ TJ = 25°C 0.1 0.2 0.1 µA V V µs NOTES 1. Test Conditions unless otherwise stated: VIN = 20V , IREF = 0. TJ = –55 to +125°C for IP1524B TJ = –25 to +85°C for IP2524B for IP3524B TJ = 0 to +70°C Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Prelim. 3/95 IP1524B SERIES SEME LAB APPLICATIONS INFORMATION Current Sensing in the Output Line Current Sensing in the Ground Line +VOUT –C.L. +C.L. 5 RSENSE RAW SUPPLY GND 4 8 12 CA 100Ω RAW SUPPLY RETURN +VOUT 13 CB 4 5 +C.L. –C.L. RETURN RETURN RSENSE Sensing Primary Current with an Emitter Resistor Oscillator Sync to an External Clock 16 EB 14 16 EA 11 3 TTL CMOS 1N914 2N2369 3.2kΩ +C.L. 3 4 3.2kΩ RSENSE –C.L. 5 A. TTL Logic B. 5 Volt CMOS Logic Driving Power Bipolar Transistors Driving Power MOSFETs +15V 1.6kΩ 12 11 12 TO LOAD D1 Q2 Q1 1.6kΩ Semelab plc. TO LOAD 0.01µF 11 Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Q1 4.7kΩ Prelim. 3/95 IP1524B SERIES SEME LAB TYPICAL PERFORMANCE CHARACTERISTICS Semelab plc. Oscillator Frequency vs. Timing Components Output Dead Time vs. Timing Capacitance Value Pulse Width Modulation Transfer Function Output Saturation Voltage Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Prelim. 3/95 IP1524B SERIES SEME LAB TYPICAL PERFORMANCE CHARACTERISTICS Error Amplifier Voltage Gain vs. Frequency Semelab plc. Undervoltage Lockout Characteristics Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Prelim. 3/95