AMC7660 DC - DC CONVERTER CONTROL CIRCUIT www.addmtek.com DESCRIPTION FEATURES The AMC7660 is designed for the applications which require DC - DC converters. It can be operated in a wide input range from 3.0V to 40V and has the controlled duty cycle oscillator, driver and high current output switch. Also, With the internal temperature compensation circuit, the AMC7660 provides an internally trimmed precision 1.5% reference voltage of 1.25V. These features make the AMC7660 suitable for step-up, step-down and voltage–inverting applications. Internally trimmed 1.5% 1.25V Reference Voltage Wide Input Operating Range: 3.0V to 40V Output Switch Current up to 1.5A Low Standby Current 100KHz operational Frequency Adjustable Output Voltage Available in 8 Pin Plastic DIP and 8 Pin S.O Packages APPLICATIONS PACKAGE PIN OUT Automobile Chargers Adaptors Mother Board External Modem ISDN Modem Scanner Cellular Phones/Radios Laptop/Notebook OC1 1 8 OC2 E1 2 7 IS CT 3 6 VCC GND 4 5 VIN- M PACKAGE (TOP VIEW) OC1 1 8 OC2 E1 2 7 IS CT 3 6 VCC GND 4 5 VIN- DM PACKAGE (TOP VIEW) ORDER INFORMATION TA (OC) 0 to 70 0 to 70 Note: Plastic DIP 8-pin AMC7660M AMC7660MF(Lead Free) Plastic SO-8 8-pin AMC7660DM AMC7660DMF(Lead Free) M 1.All surface-mount packages are available in Tape & Reel. 2.The letter ”F” is marked for Lead Free process. Copyright © 2006 ADDtek Corp. DM Append the letter “T” to part number (i.e. AMC7660DMT). 1 DD057_C -- JUNE 2006 AMC7660 ABSOLUTE MAXIMUM RATINGS Power Supply Voltage (VCC) ………………………………………………………………………………..…40V Operating Junction temperature Plastic (M, DM Package) …………………………………………………………………………….…….. 150 OC Storage Temperature Range …………………………………………………………………...…. -65 OC to 150 OC Lead temperature (Soldering, 10 seconds) …………………………………………………………..………300 OC Note 1: Exceeding these ratings could cause damage to the device. negative out of the specified terminal. All voltages are with respect to Ground. Currents are positive into, THERMAL DATA M PACKAGE: Thermal Resistance-Junction to Ambient, θJA DM PACKAGE: Thermal Resistance-Junction to Ambient, θJA 95 OC/W 165 OC/W BLOCK DIAGRAM IS VCC 7 6 OC2 8 5 VINS Q Q2 OC1 1 R 1.25V Q1 100 I sense E1 2 CT Oscillator 4 GND 3 CT Copyright © 2006 ADDtek Corp. 2 DD057_C -- JUNE 2006 AMC7660 RECOMMENDED OPERATING CONDITIONS Recommended Operating Parameter Symbol Min. Typ. Max. VIR Comparator Input Voltage -0.3 to + 40 VOC1 Switch Collector Voltage 40 VE1 Switch Emitter Voltage (VPin1=40V) 40 V Switch Collector to Emitter Voltage 40 CE1 VC2 Driver Collector Voltage 40 IC2 Driver Collector Current (Note 1) 100 ISWITCH Switch Current 1.5 CT Oscillator Timing Capacitor (connected to CT pin) 1.0 Operating Ambient Temperature Range TA 0 to +70 Units V V V V V mA A nF °C Note 1: Maximum package power dissipation limits must be observed. ELECTRICAL CHARACTERISTICS VCC=5.0 V, TA=0 C to 70 C, unless otherwise specified. O O Parameter Symbol OSCILLATOR Frequency Fosc Charge Current Ichg Discharge Current Idischg Discharge to Charge Current Ratio Idischg/Ichg Current Limit Sense Voltage VIS OUTPUT SWITCH Saturation Voltage, Darlington Connection VCE1(sat) Saturation Voltage DC Current Gain Collector Off－State Current VCE1(sat) hFE IC(off) Test Conditions O VIN- = 0 V, CT = 1.0 nF, TA = 25 C VCC = 5.0 V to 40 V, TA = 25 OC VCC = 5.0 V to 40 V, TA = 25OC IS to VCC, TA = 25 OC Ichg = Idischg, TA = 25 OC ISW = 1.0 A, OC1, OC2 connected ISW = 1.0 A, 82 Ω connected from OC2 to VCC, Forced β = 20 ISW = 1.0 A, VCE = 5.0 V, TA = 25 O C VCE = 40 V AMC7660 Min. Typ. Max. Units 24 24 140 5.2 250 33 35 220 6.5 300 42 42 260 7.5 350 KHz µA µA mV - 0.9 1.3 V - 0.4 0.7 V 50 75 - - - 0.01 100 µA COMPARATOR Threshold Voltage Threshold Voltage Line Regulation Input Bias Current Vth Vth(line) IIB TA = 25 OC TA =0 OC to 70 OC VCC = 3.0 V to 40 V VIN- = 0 V 1.23 1.25 1.27 1.22 1.28 1.4 5.6 -20 -400 V mV nA TOTAL DEVICE Supply current Copyright © 2006 ADDtek Corp. ICC VCC = 5.0 V to 40 V, CT = 1.0nF, Pin 7 = VCC, VIN- > Vth, Pin 2= Gnd, remaining pins open 3 - 3.0 3.9 DD057_C -- mA JUNE 2006 AMC7660 CHARACTERIZATION CURVES VCC = 5V, Pin 1, 5, 8 open VCC = 5V, Pin 1, 5, 8 open CT = 470pF CT = 470pF CT pin (PIN#3) waveform CT pin (PIN#3) waveform VCC = 5V, Pin 1, 5, 8 open VCC = 25V, Pin 1, 5, 8 open CT = 470pF CT = 470pF CT pin (PIN#3) waveform CT pin (PIN#3) waveform VCC = 25V, Pin 1, 5, 8 open VCC =25V, Pin 1, 5, 8 open CT = 470pF CT = 470pF CT pin (PIN#3) waveform Copyright © 2006 ADDtek Corp. CT pin (PIN#3) waveform 4 DD057_C -- JUNE 2006 AMC7660 CHARACTERIZATION CURVES VCC = 5V, Pin 1, 5, 8 open VCC = 5V, Pin 1, 5, 8 open CT = 1nF CT = 1nF CT pin (PIN#3) waveform CT pin (PIN#3) waveform VCC = 5V, Pin 1, 5, 8 open VCC = 25V, Pin 1, 5, 8 open CT = 1nF CT = 1nF CT pin (PIN#3) waveform CT pin (PIN#3) waveform VCC = 25V, Pin 1, 5, 8 open VCC =25V, Pin 1, 5, 8 open CT = 1nF CT = 1nF CT pin (PIN#3) waveform Copyright © 2006 ADDtek Corp. CT pin (PIN#3) waveform 5 DD057_C -- JUNE 2006 AMC7660 CHARACTERIZATION CURVES VCC = 25V, 500mA load VCC = 25V, 500mA load 23.3V CT = 470pF CT = 470pF CT pin waveform - 0.8V 5V output E1 pin (PIN#2) waveform Step down 5V output performance on 5V step down converter Copyright © 2006 ADDtek Corp. 6 DD057_C -- JUNE 2006 AMC7660 Figure 1 – Step-Up Converter Application Circuits 47K V IN 12V R1 0.22 Rsc 7 100uF 6 180 8 5 OC2 170uH VOUT 28V/175mA OC1 1 Co D1 330uF Q Q2 R2 2.2K S R 1.25V Q1 100 I sense 2 Oscillator CT 4 3 1.5nF Figure 2 – Step-Down Converter Application Circuit 3.6K V IN 25V R1 0.33 Rsc 7 8 100uF 6 5 OC2 1 OC1 Q2 Q R R2 1.2K S 1.25V Q1 VOUT 5V/500mA 100 220uH Co 470uF I sense 2 Oscillator CT D1 4 3 470pF Copyright © 2006 ADDtek Corp. 7 DD057_C -- JUNE 2006 AMC7660 Figure 3 – Voltage Inverting Converters 953 Co 1000uF V IN 4.5V to 6.0V R2 0.24 Rsc 7 8 100uF 6 5 OC2 8.2K S V OUT -12V/100mA 1 OC1 Q2 Q R R1 1.25V Q1 100 D1 I sense 2 CT 88uH Oscillator 4 3 1.5nF Note: For step-up, step-down or voltage inverting applications requiring peak current greater than 1.5A, external boost current circuitry by NPN or PNP transistors can be used. Copyright © 2006 ADDtek Corp. 8 DD057_C -- JUNE 2006 AMC7660 Typical Design Reference Table: Calculation Step-Down Step-Up Voltage-Inverting ton/toff Vout + VF Vin(min) − Vsat− Vout Vout + VF − Vin(min) Vin(min) − Vsat ?Vout? + VF Vin − Vsat ton + toff 1 f 1 f 1 f toff ton + toff ton/toff + 1 ton + toff ton/toff + 1 ton + toff ton/toff + 1 ton (ton + toff) − toff (ton + toff) − toff (ton + toff) − toff CT 4.0 × 10 ton 4.0 × 10 ton 4.0 × 10-5 ton Ipk(switch) 2Iout(max) 2Iout(max) (ton/toff + 1) 2Iout(max) (ton/toff + 1) RSC 0.3/Ipk(switch) 0.3/Ipk(switch) 0.3/Ipk(switch) L(min) -5 ( (V CO in(min) − Vsat− Vout) Ipk(switch) -5 )t on(max) ( (V I in(min) − Ipk(switch)( ton + toff) 8Vripple(pp) VF: Forward Voltage drop of the output rectifier Vsat: Saturation voltage of the output switch. Vsat) pk(switch) 9 )t on(max) ( (V I in(min) − Vsat) pk(switch) Iout ton Vripple(pp) 9 )t on(max) Iout ton Vripple(pp) The following power supply characteristics must be chosen: Vin - Nominal input voltage Vout - Desired output voltage, ?Vout? = 1.25(1 + R1/R2) Iout - Desired output current. fmin – Minimum desired output switching frequency at the selected values of Vin and IO Vripple(pp) – Desired peak – to – peak output ripple voltage. Application concerns: To get the best regulation performance, Low ESR capacitors at Vout are suggested. Copyright © 2006 ADDtek Corp. 9 DD057_C -- JUNE 2006 AMC7660 PACKAGE 8-Pin Plastic DIP INCHES 5 8 MIN MAX MIN TYP MAX A 0.355 0.365 0.400 9.02 9.27 10.16 B 0.240 0.250 0.280 6.10 6.35 7.11 B 1 4 A L F TYP MILLIMETERS C - - 0.210 - - 5.33 D - 0.018 - - 0.46 - F - 0.060 - - 1.52 - G - 0.100 - - 2.54 - H 0.050 - 0.090 1.27 - 2.29 J 0.008 - 0.015 0.20 - 0.38 K 0.115 0.130 0.150 2.92 3.30 3.81 L 0.300 BSC. C J K H G M D M - 7º 7.62 BSC. 15º - 7º 15º 8-Pin Plastic S.O.I.C. INCHES A B P F D L C SEATING PLAN K Copyright © 2006 ADDtek Corp. MIN TYP MAX MIN TYP MAX A 0.183 - 0.202 4.65 - 5.13 B 0.144 - 0.163 3.66 - 4.14 C 0.068 - 0.074 1.73 - 1.88 D 0.010 - 0.020 0.25 - 0.51 F - 0.035 0.38 - 0.89 0.015 G G M J 10 MILLIMETERS 0.050 BSC 1.27 BSC J 0.007 - 0.010 0.19 - 0.25 K 0.005 - 0.010 0.13 - 0.25 L 0.189 - 0.205 4.80 - 5.21 M - - 8º - - 8º P 0.228 - 0.244 5.79 - 6.20 DD057_C -- JUNE 2006 AMC7660 IMPORTANT NOTICE ADDtek reserves the right to make changes to its products or to discontinue any integrated circuit product or service without notice, and advises its customers to obtain the latest version of relevant information to verify, before placing orders, that the information being relied on is current. A few applications using integrated circuit products may involve potential risks of death, personal injury, or severe property or environmental damage. ADDtek integrated circuit products are not designed, intended, authorized, or warranted to be suitable for use in life-support applications, devices or systems or other critical applications. Use of ADDtek products in such applications is understood to be fully at the risk of the customer. In order to minimize risks associated with the customer’s applications, the customer should provide adequate design and operating safeguards. ADDtek assumes to no liability to customer product design or application support. ADDtek warrants the performance of its products to the specifications applicable at the time of sale. ADDtek Corp. 9F, No. 20, Sec. 3, Bade Rd., Taipei, Taiwan, 105 TEL: 2-25700299 FAX: 2-25700196 Copyright © 2006 ADDtek Corp. 11 DD057_C -- JUNE 2006