IP5661C IP5561C SEME LAB TOP VIEW VCC 1 8 GND VZ 2 7 OUTPUT FEEDBACK 3 6 CURRENT SENSE GAIN 4 5 RT/CT SWITCHED–MODE POWER SUPPLY CONTROL CIRCUIT FEATURES • STABILISED POWER SUPPLY • TEMPERATURE COMPENSATED REFERENCE SOURCE J Package – 8 Pin Ceramic DIP N Package – 8 Pin Plastic DIP D Package – 8 Pin Plastic (150) SOIC • SAWTOOTH GENERATOR • PULSE WIDTH MODULATOR BLOCK DIAGRAM • CURRENT LIMITING RT CT • 8 PIN DIP 5 VCC REFERENCE VOLTAGE DESCRIPTION SAWTOOTH GENERATOR ERROR AMP FEEDBACK GAIN 3 OUTPUT LATCH R 0.5V CURRENT SENSE 7 S PWM 4 2 STABILISED SUPPLY 6 8.2V 1 8 VCC GND Vz The IP5561 is a control circuit for use in switched mode power supplies. This single monolithic chip incorporates all the control and supervisory (protection) functions required in switched mode power supplies, including an inter nal temperature compensated reference source, internal zener reference, sawtooth generator, pulse width modulator, output stage and cycle by cycle current limit. Order Information Part Number IP5561 IP5561C J–Pack 8 Pin ✔ ✔ N–Pack 8 Pin D–8 8 Pin ✔ ✔ Temp. Range -55 to +125°C 0 to +70°C Note: To order, add the package identifier to the part number. eg. IP5561J IP5561CD–8 ABSOLUTE MAXIMUM RATINGS (Tcase = 25°C unless otherwise stated) SUPPLY Voltage Sourced Current Sourced 18V 30mA OUTPUT TRANSISTOR TJ TSTG Output Current Collector Voltage (Pin 7) Operating Junction Temperature Storage Temperature Range Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. 40mA 18V See Ordering Information –55 to +150°C Prelim. 4/95 IP5661C IP5561C SEME LAB ELECTRICAL CHARACTERISTICS (TJ = 25°C unless otherwise stated) Parameter Test Conditions Min. IP5561 Typ. Max. Min. IP5561C Typ. Max. Units REFERENCE SECTIONS 3.69 Internal Reference Voltage (VREF) TJ = Over Temp. Range 3.65 3.84 3.57 3.88 3.55 ±100 Temperature Coefficient of VREF Internal Reference (VZ) 3.75 IL = -7mA 7.8 Temperature Coefficient of VZ 8.2 3.75 3.96 3.98 ppm/°C ±100 8.8 7.8 ±200 8.2 V 8.8 V ppm/°C ±200 OSCILLATOR SECTION TJ = Over Temp. Range Frequency Range Initial Accuracy Oscillator Duty Cycle Range 50 100k 50 12 fO = 20kHz 0–90 100k 12 0–98 0–90 Hz % 0–98 CURRENT LIMITING Vpin6 = 250mV IIN –2 TJ = Over Temp. Range Single Pulse Inhibit Delay –10 –2 -20 –10 -20 Inhibit Delay Time IOUT = 20mA 0.88 1.10 0.88 1.10 for 20% overdrive IOUT = 40mA 0.7 0.8 0.7 0.8 0.50 0.60 0.50 0.60 Current Limit Trip Level 0.40 0.40 µA µs V ERROR AMPLIFIER Output Voltage Swing (VOH) 6.2 6.2 Output Voltage Swing (VOL) 0.7 Open Loop Gain 0.7 60 Feedback Resistor Small Signal Bandwidth dB 60 10k Ω 10k 3 V MHz 3 OUTPUT STAGE VCE(sat) IC = 20mA TJ = Over Temp. Range Output Current TJ = Over Temp. Range 0.4 20 0.4 V mA 20 SUPPLY VOLTAGE/CURRENT Supply Current (ICC) Supply Voltage (VCC) IZ = 0, Voltage Fed TJ = Over Temp. Range ICC = 10mA, Voltage Fed 20 ICC = 30mA, Voltage Fed 20 21 10 10 13 13 22 19 30 20 10.5 8 21 24 30 mA V LOW SUPPLY PROTECTION Pin 1 Threshold 8 9 9 10.5 V NOTES 1) Test Conditions: VCC = 12V , TJ = 25°C unless otherwise stated 2) Tests marked TJ = Over Temp. Range apply over the full temperature range ie. TJ = -55 to +125°C for IP5561 TJ = 0 to +70°C for IP5561C Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Prelim. 4/95 IP5661C IP5561C SEME LAB TYPICAL PERFORMANCE CHARACTERISTICS — ERROR AMPLIFIER Open Loop Gain 60 -30 50 -60 40 GAIN (dB) PHASE ANGLE (˚) Open Loop Phase 0 -90 30 -120 20 -150 10 -180 0 1k 10k 100k 1M 10M 1k 10k 1M 100k 10M FREQUENCY (Hz) FREQUENCY (Hz) Transfer Curve of Pulse Width Modulator Duty Cycle vs Input Voltage Maximum Duty Cycle vs Base Voltage on Q1 100 90 90 δ MAX – MAXIMUM DUTY CYCLE (%) 100 δ – DUTY CYCLE (%) 80 70 60 50 40 30 20 10 0 80 70 60 50 40 30 20 10 0 0 1 2 3 4 5 6 0 1 2 3 4 5 V V Pin 1 Pin 4 Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Prelim. 4/95 IP5661C IP5561C SEME LAB TYPICAL PERFORMANCE CHARACTERISTICS — ERROR AMPLIFIER Power Derating Curve Slow Start Voltage VPIN4 1.00 PD MAX (W) 0.75 0.50 0.25 0.00 25 50 75 100 125 t t = R'C 150 TA AMBIENT TEMPERATURE (˚C) PD = VCC ICC + ( VCC – VZ ) IZ + ( Vpin7 Ipin7 x δ ) Typical Frequency Plot vs RT and CT Start-up Circuit (Optional) 200 OSCILLATOR FREQUENCY (kHz) VZ 2 R=5 kΩ 100 R=1 0 50 IP5561 R1 kΩ 4 2 R=2 0kΩ RT R=4 0kΩ 10 V1 IP5561 C Q1 R2 5 CT 5 δmax = f 1 1.5 2 2.5 3 3.5 4 TIMING CAPACITANCE Semelab plc. 4.5 ( R2 R1+R2 VZ + VBE Q1 ) 5 (nF) Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Prelim. 4/95