L1 GS SS14 EXT AIC1639 GND. 100mA Load Current Step-Up Converter

Transcription

1 FEATURES A Guaranteed Start-Up from less than 0.9 V. High Efficiency. ow Quiescent Current. ess Number of External Components needed. ow Ripple and ow Noise. Fixed Output Voltage: 2.7, 3.0V, 3.1V, 3.3V, 3.6V, 5V and 5.5V. river for External Transistor. Space Saving package: SOT-23, SOT-89 and TO-92. APPICATIS Pagers. Cameras. Wireless Microphones. Pocket Organizers. Battery Backup Suppliers. Portable Instruments. AIC Cell, 3-Pin, Step-Up C/C Controller ESCRIPTI The AIC1639 is a high efficiency step-up C/C controller for applications using 1 to 4 battery cells. Only three external components are required to deliver a fixed output voltage of 2.7, 3.0V, 3.1V, 3.3V, 3.6V, 5V or 5.5V. The AIC1639 starts up from less than 0.9V input with 1mA load. Pulse Frequency Modulation scheme brings optimized performance for applications with light output loading and low input voltages. The output ripple and noise are lower compared with the circuits operating in PSM mode. The PFM control circuit operating in 100KHz (max.) switching rate results in smaller passive components. The space saving SOT-23, SOT- 89 and TO-92 packages make the AIC1639 an ideal choice of C/C controller for space conscious applications, like pagers, electronic cameras, and wireless microphones. TYPICA APPICATI CIRCUIT VIN 1 Provided with an external transistor driver pin (EXT), the AIC1639 is recommended for applications requiring current as large as several tens to several hundreds of milli-amperes. + C1 47µF 1 33µH GS SS14 V *Q1 2S13 R1 300 C2 10nF EXT AIC1639 GN V + C3 100µF *Q1: Sanyo 2513S-TC 60V/5A/20W 100mA oad Current Step-Up Converter Analog Integrations Corporation Si-Soft Research Center S-1639G A1, No.1, i-hsin Rd. I, Science Park, Hsinchu 300, Taiwan, R.O.C. TE: FAX:

2 AIC1639 ORERING INFORMATI AIC1639-XX X X XX PACKING TYPE TR: TAPE & REE BG: BAG PACKAGE TYPE X: SOT-89 Z: TO-92 U: SOT-23 SOT-89 TOP VIEW 1: GN 2: V 3: EXT ORERING INFORMATI C: Commercial P: ead Free Commercial G: Green Package PUT VOTAGE 27: 2.7V 30: 3.0V 31: 3.1V 33: 3.3V 36: 3.6V 50: 5.0V EX: AIC CXTR 2.7V Version, in SOT-89 Package & TR Packing Type AIC PXTR 2.7V Version, in SOT-89 ead Free TO-92 TOP VIEW 1: GN 2: V 3: EXT SOT-23 TOP VIEW 1: GN 2: EXT 3: V Package & TR Packing Type 2

3 AIC1639 SOT-23 MARKING Part No. CU PU GU AIC B27 B27P B27G AIC B30 B30P B30G AIC B31 B31P B31G AIC B33 B33P B33G AIC B36 B36P B36G AIC B50 B50P B50G AIC B55 B55P B55G SOT-89 MARKING Part No. CX PX GX AIC XX AU27 AU27P AU27G AIC XX AU30 AU30P AU30G AIC XX AU31 AU31P AU31G AIC XX AU33 AU33P AU33G AIC XX AU36 AU36P AU36G AIC XX AU50 AU50P AU50G AIC XX AU55 AU55P AU55G 3

4 AIC1639 ABSOUATE MAXIMUM RATINGS Supply Voltage (V Pin)..6V EXT pin Voltage.-0.3V to Vout+0.3V EXT pin Current.± 50mA Operating Temperature Range.-40 C to 85 C Maximum Junction Temperature 125 C Storage Temperature Range -65 C to 150 C ead Temperature (Soldering 10 Sec.) 260 C Thermal Resistance Junction to Case SOT C/W TO C/W SOT C/W Thermal Resistance Junction to Ambient SOT-23 1 C/W (Assume no ambient airflow, no heatsink) TO C/W SOT C/W Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. TEST CIRCUIT AIC V V EXT F GN Oscillator Test Circuit 4

5 AIC1639 EECTRICA CHARACTERISTICS (T A =25 C, I O =10mA, Unless otherwise specified) (Note1) PARAMETER TEST CITIS SYMBO MIN. TYP. MAX. UNIT AIC V IN =1.8V AIC V IN =1.8V AIC V IN =1.8V Output Voltage AIC V IN =2.0V V V AIC V IN =2.0V AIC V IN =3.0V AIC V IN =3.0V Input Voltage V IN 6 V Start-Up Voltage I =1mA, V IN :0 2V V START V Hold-on Voltage I =1mA, V IN :2 0V V HO 0.6 V No-oad Input Current I =0mA I IN 18 µa Supply Current 1 Supply Current 2 EXT H On-Resistance EXT On-Resistance AIC AIC AIC AIC AIC AIC AIC EXT at no load, V IN =V x 0.95 Measurement of the IC input current (V Pin) EXT at no load, V IN =V Measurement of the IC input current (V Pin) AIC AIC AIC AIC AIC AIC AIC V EXT =V 0.4V AIC AIC I µa I 2 7 µa R EXTH R EXT Ω Ω 5

6 AIC1639 AIC AIC AIC AIC AIC V EXT = 0.4V EECTRICA CHARACTERISTICS (Continued) PARAMETER TEST CITIS SYMBO MIN. TYP. MAX. UNIT V IN =V x 0.95 Oscillator uty Cycle Measurement of the EXT Pin UTY % Waveform Max. Oscillator Freq. V IN =V x 0.95 Measurement of the EXT Pin Waveform F OSC KHz Efficiency η % Note 1: Specifications are production tested at T A =25 C. Specifications over the -40 C to 85 C operating temperature range are assured by design, characterization and correlation with Statistical Quality Controls (SQC). 6

7 AIC1639 TYPICA PERFORMANCE CHARACTERISTICS Inductor (1) : 33µH (Pin Type) Capacitor (C1) : 47µF (Tantalum Type) iode (1) : 1N5819 Schottky Type Transistor (Q1) : 2S Output Voltage (V) V IN =0.9V V IN =1.2V V IN =1.5V V IN =2.0V V IN =1.8V Efficiency (%) V IN =0.9V V IN =1.2V V IN =1.5V V IN =2.0V V IN =1.8V Fig. 1 AIC oad Regulation (=33µH) Fig. 2 AIC Efficiency (=33uH) Output Voltage (V) V IN =0.9V V IN =1.2V V IN =1.5V V IN =2.0V V IN =1.8V Fig. 3 AIC oad Regulation (=33µH) Efficiency (%) 85 V IN =2.0V V IN =1.8V 75 V IN =1.5V 70 V IN =1.2V 65 V IN =0.9V Fig. 4 AIC Efficiency (=33µH) TYPICA PERFORMANCE CHARACTERISTICS (Continued) Output Voltage (V) V IN =1.2V V IN =1.5V V IN =2.0V Efficiency (%) V IN =1.5V V IN =2.0V V IN =0.9V Fig. 5 AIC oading Regulation (=33µH) Fig. 6 AIC Efficiency (=33µH) 7

8 AIC Output Voltage (V) V IN =0.9V V IN =1.5V V IN =1.2V V IN =2.0V V IN =3.0V Fig. 7 AIC oad Regulation (=33µH) Efficiency (%) V IN =0.9V V IN =1.5V V IN =1.2V V IN =2.0V Fig. 8 AIC Efficiency (=33µH) V IN =3.0V Output Voltage (V) Start up Input Voltage (V) Start up Hold on Hold on Fig. 9 AIC Start-up & Hold-on Voltage (=33µH) Fig. 10 AIC Start-up & Hold-on Voltage (=33µH) 8

9 AIC1639 TYPICA PERFORMANCE CHARACTERISTICS (Continued) Input Voltage (V) Start up Hold on Input Voltage (V) Start up Hold on Fig. 11 AIC Start-up & Hold-on Voltage (=33µH) Fig. 12 AIC Start-up & Hold-on Voltage (=33µH) Start up Start up Input Voltage (V) Hold on Input Voltage (V) Hold on Fig. 13 AIC Start-up & Hold-on Voltage (=33µH) Fig. 14 AIC Start-up & Hold-on Voltage (=33µH) Output Voltage (V) V =5.0V V = 3.3V V = 3.0V V = 2.7V Switching Frequency (khz) V = 5.0V V = 3.3V V = 3.0V V = 2.7V Fig. 15 AIC1639 Output Voltage vs. Temperature Fig. 16 AIC1639 Switching Frequency vs. Temperature 9

10 AIC1639 TYPICA PERFORMANCE CHARACTERISTICS (Continued) Maximum uty Cycle (%) V = 2.7V V = 3.0V V = 3.3V V = 5.0V Fig. 17 AIC1639 Maximum uty Cycle vs. Temperature Supply Current I1 (µa) V = 5.0V V = 3.3V V = 3.0V V = 2.7V Temperature ( C) Fig. 18 AIC1639 Supply Current vs. Temperature Resistance (Ω) V = 2.7V V = 3.0V V = 3.3V V = 5.0V Resistance (Ω) V = 2.7V V = 3.0V V = 3.3V V = 5.0V Temperature ( C) Fig. 19 AIC1639 EXT "" On-Resistance Temperature ( C) Fig. 20 AIC1639 EXT "H" On-Resistance 10

11 AIC1639 BOCK IAGRAM V 1.25V REF. 1M - + EXT GN Enable OSC, 100KHz PIN ESCRIPTIS PIN 1 : GN - Ground. Must be low impedance; solder directly to ground plane. PIN 2 : V - IC supply pin. Connect V to the regulator output. PIN 3: EXT - Push Pull driver output for external power switch. APPICATI INFORMATI GENERA ESCRIPTI AIC1639 PFM (pulse frequency modulation) controller ICs combine a switch mode regulator, push pull driver (AIC1639), precision voltage reference, and voltage detector in a single monolithic device. They offer both extreme low quiescent current, high efficiency, and very low gate threshold voltage to ensure start-up with low battery voltage ( 0.8V typ.). esigned to maximize battery life in portable products, and minimize switching losses by only switching as needed service the load. PFM controllers transfer a discrete amount of energy per cycle and regulate the output voltage by modulating switching frequency with the constant turn-on time. Switching frequency depends on load, input voltage, and inductor value, and it can range up to 100KHz. When the output voltage drops, the error comparator enables 100kHz oscillator that turns on the MOSFET around 7.5µS and 2.5µS off time. Turning on the MOSFET allows inductor current to ramp up, storing energy in a magnetic field. When MOSFET turns off that forces inductor current through diode to the output capacitor and load. As the stored energy is depleted, the current ramp down until the diode turns off. At this point, inductor may ring due to residual energy and stray capacitance. The output capacitor stores charge when current flowing through the diode is high, and release it when current is low, thereby maintaining a steady voltage across the load. As the load increases, the output capacitor discharges faster and the error comparator initiates cycles sooner, increasing the switching frequency. The maximum duty cycle ensure adequate time for energy transfer to output during 11

12 AIC1639 the second half each cycle. epending on circuit, PFM controller can operate in either discontinuous mode or continuous conduction mode. The continuous conduction mode means that the inductor current does not ramp to zero during each cycle. V EXT I IN I PK V IN I SW I IN I I EXT SW + V I I Isw Ico V SW V EXT t Continuous Conduction Mode I IN I PK I SW I I T IS V SW Charge Co. ischarge Co. iscontinuous Conduction Mode t At the boundary between continuous and discontinuous mode, output current (IOB) is determined by I OB = V VIN + V * 1 V * 2 IN where V is the diode drop, X = (R T + RS) * T * ( 1 x) R = Switch turn on resistance, R S = Inductor C resistance T = Switch time In the discontinuous mode, the switching frequency (Fsw) is F 2() * (V + V V = 2 2 VIN * T ) * (I ) * (1 IN SW + In the continuous mode, the switching frequency is x) 12

13 AIC fsw = T ( V + V VIN) * (V + V V SW x VIN VSW * [1+ ( )] 2 V + V VSW 1 V + V VIN * T V + V VSW where Vsw = switch drop and proportion to output current. INUCTOR SEECTI To operate as an efficient energy transfer element, the inductor must fulfill three requirement. First, the inductance must be low enough for the inductor to store adequate energy under the worst case condition of minimum input voltage and switch time. Second, the inductance must also be high enough so maximum current rating of AIC1639 and inductor are not exceed at the other worst case condition of maximum input voltage and time. astly, the inductor must have sufficiently low C resistance so excessive power is not lost as heat in the windings. But unfortunately this is inversely related to physical size. Minimum and Maximum input voltage, output voltage and output current must be established before and inductor can be selected. In discontinuous mode operation, at the end of the switch time, peak current and energy in the inductor build according to ) I PK = R V VIN IN VIN R + R * 1 exp( + RS x * ( T) * 1 2 * T (simple lossless equation), where X = (R 1 E = * IPK 2 T + RS) 2 S * T ) Power required from the inductor per cycle must be equal or greater than P f SW = (V + V V IN ) * (I 1 ) * ( fsw In order for the converter to regulate the output. When loading is over IOB, PFM controller operates in continuous mode. Inductor peak current can be derived from I PK V = * I + V V VIN VSW V + IN V 2 Valley current (Iv) is I V V = V * + V V VIN VSW IN V 2 E * T SW SW SW * x 2 * T x * I 2 x 1 2 ) x *

14 AIC1639 Table 1 Indicates resistance and height for each coil. Power Inductor Type Inductance ( µh ) Resistance ( Ω ) Rated Current (A) height (mm) Sumida SMT Type C54 Hold SMT Type PM Hold SMT Type PM Huan Feng PIN Type V m CAPACITOR SEECTI A poor choice for a output capacitor can result in poor efficiency and high output ripple. Ordinary aluminum electrolytic, while inexpensive may have unacceptably poor ESR and ES. There are low ESR aluminum capacitors for switch mode C-C converters which work much better than generalpurpose unit. Tantalum capacitors provide still better performance at more expensive. OS-C capacitors have extremely low ESR in a small size. If capacitance is reduced, output ripple will increase. Most of the input supply is supplied by the input bypass capacitor, the capacitor voltage rating should be at least 1.25 times greater than a maximum input voltage. IOE SEECTI COMPENT POWER ISSIPATI Operating in discontinuous mode, power loss in the winding resistance of inductor can be approximate equal to P = 2 T * 3 * V + V V ( RS) * * ( P) where P =V * I ; R S =Inductor C R; V = iode drop. The power dissipated in a switch loss is Psw = 2 3 T * * ( R) * ( I) * (P) The power dissipated in rectifier diode is P V = V * ( P) Speed, forward drop, and leakage current are the three main consideration in selecting a rectifier diode. Best performance is obtained with Schottky rectifier diode such 1N5819. Motorola makes MBR0530 in surface mount. For lower output power a 1N4148 can be used although efficiency and start-up voltage will suffer substantially. 14

15 AIC1639 PHYSICA IMENSIS (unit: mm) SOT-23 e S Y M B O MIN. SOT-23 MIIMETERS MAX. A E1 E A A b A A e1 SEE VIEW B c E b E A2 A1 A WITH PATING c e e BSC 1.90 BSC 0.60 REF 0.60 θ BASE META SECTI A-A 1 VIEW B θ GAUGE PANE SEATING PANE Note: 1.Refer to JEEC MO imension and E1 do not include mold flash, protrusions or gate burrs. Mold flash, protrusion or gate burrs shall not exceed 10 mil per side. 3.Controlling dimension is millimeter, converted inch dimensions are not necessarily exact. 15

16 AIC1639 SOT-89 1 A C S Y M B O MIN. SOT-89 MIIMETERS MAX. A E H B B C e E e1 e e BSC 3.00 BSC H B1 B Note: 1.Refer to JEEC TO-243AA. 2.Controlling dimension is millimeter, converted inch dimensions are not necessarily exact. 16

17 AIC1639 TO-92 S Y M B O MIN. TO-92 MIIMETERS MAX. A b E e e j S Note: 1.Refer to JEEC TO Controlling dimension is millimeter, converted inch dimensions are not necessarily exact. Note: Information provided by AIC is believed to be accurate and reliable. However, we cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AIC product; nor for any infringement of patents or other rights of third parties that may result from its use. We reserve the right to change the circuitry and specifications without notice. ife Support Policy: AIC does not authorize any AIC product for use in life support devices and/or systems. ife support devices or systems are devices or systems which, (I) are intended for surgical implant into the body or (ii) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 17