AP1602 ANACHIP | Alldatasheet
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This datasheet contains new product information. Anachip Corp. reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sale of the product. Rev. 0.1 Apr. 14, 2004 Features -A Guaranteed Start-Up from less than 0.9 V. -High Efficiency. -Low Quiescent Current. -Less Number of External Components needed. -Low Ripple and Low Noise. -Space Saving Packages: SOT89-5 Applications -Pagers. -Cameras. -Wireless Microphones. -Pocket Organizers. -Battery Backup Suppliers. -Portable Instruments. General Description The AP1602 is a high efficiency step-up DC/DC converter for applications using 1 to 2 NiMH battery cells. Only three external components are required to deliver a fixed output voltage of 3.3V. The AP1602 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 SOT89-5 packages make the AP1602 an ideal choice of DC/DC converter for space conscious applications, like pagers, electronic cameras, and wireless microphones. Pin Assignments LX GND OUT REF AP1602A SHDN OUT GND LX FB SOT89-5L AP1602B REF Pin Descriptions Pin No. Pin Name A B
Description
1.2V Reference Voltage. Bypass with a 0.1µF capacitor. OUT Power Output. OUT provides bootstrap power to the IC. LX N-Channel and P-Channel Power MOSFET Drain GND Ground SHDN Shutdown Input. Drive high (>80% of VOUT) for operating mode. Drive low (<20% of VOUT) for shutdown mode. Connect to OUT for normal operation. FB Feedback pin Ordering Information Package AP1602 X X X X Packing Blank : Tube A : Taping Y: SOT89-5L Lead Free Blank : Normal L : Lead Free Package Version A: A version B: B version
Anachip Corp. Block Diagram S Q R F/F TRIG One-Shot Q One-Shot Q TRIG Maximum On-Time One-Shot Error Amplifier Current-Limit Amplifier Zero Crossing Amplifier Minimum Off-Time One-Shot OUT LX GND FB REF 0.1uF 22uH 0.1uF 47uF 47uF SHDN P N VIN EN Absolute Maximum Ratings Symbol Parameter Rating Unit VCC Supply Voltage (OUT to GND) -0.3 to 5.5 V VREF REF to GND -0.3 to VOUT+0.3 V VSW Switch Voltage (LX to GND) -0.3 to VOUT+0.3 V IOUT Output Current (OUT) -0.8 to 0.8 A ISW Switch Current (LX) -0.8 to 0.8 A TST Storage Temperature Range -65 to +150 oC TOT Operation Temperature Range -40 to +80 oC
Anachip Corp. Electrical Characteristics (RL = ∞, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) Symbol Parameter Conditions Min. Typ. Max. Unit Minimum Input Voltage 0.9 V VIN Operating Voltage TA = +25°C 1.1 5.5 V Start-Up Voltage TA = +25°C, RL = 3kΩ (Note 1) 0.9 1.1 V Start-Up Voltage Tempco mV/°C Output Voltage Range 5.5 V IOUT Steady-State Output Current (Note2) (VOUT = 3.3V) 150 220 mA VREF Reference Voltage IREF=0 1.176 1.2 1.224 V VOUT Output Voltage 3.17 3.3 3.43 V TEMPCO Reference Voltage Tempco 0.024 mV/°C VREF_LOAD Reference Voltage Load Regulation IREF=0 to 80 μA mV VREF_LINE Reference Voltage Line Regulation VIN=1.1V to 3.6V 0.08 2.5 mV/V RDS(ON) Internal NFET, PFET On-Resistance ILX=100mA 0.3 0.6 Ω ILIM LX Switch Current Limit (NFET) 0.4 0.5 0.65 A ILEAK LX Leakage Current VLX=0, 5.5V; VOUT=5.5V 0.05 μA Operating Current into OUT VOUT=3.3V µA Shutdown Current into OUT SHDN =GND 0.1 µA Efficiency VOUT=3.3V, ILOAD=200mA tON LX Switch On-Time µs tOFF LX Switch Off-Time 0.8 1.2 µs ISHDN SHDN Input Current VSHDN =0 or VOUT 0.07 nA VIL 0.2 VIH SHDN Input Voltage Based on VOUT Voltage 0.8 VOUT Note 1: Start-up voltage operation is guaranteed with the addition of a Schottky MBR0520 external diode between the input and output. Note 2: Steady-state output current indicates that the device maintains output voltage regulation under load. Typical Application Circuit SHDN LX OUT REF 0.1uF 22uH 220uF 100uF VIN ON OFF Fixed Output ( 3.3V ) GND 1.1V to 3.6V Optional
Anachip Corp. Typical Performance Characteristics REFERENCE OUTPUT VOLTAGE v.s. TEMPERATURE 1.14 1.15 1.16 1.17 1.18 1.19 1.2 1.21 -40 -20 100 TEMPERATURE (°C) REFERENCE OUTPUT VOLTAGE (V) MAXIMUM OUTPUT CURRENT v.s. INPUT VOLTAGE (VOUT=3.3V) 100 200 300 400 500 600 1.2 1.4 1.6 1.8 2.2 2.4 2.6 2.8 INPUT VOLTAGE (V) MAXIMUM OUTPUT CURRENT (mA) START-UP VOLTAGE v.s. LOAD CURRENT 0.2 0.4 0.6 0.8 1.2 1.4 1.6 1.8 0.01 0.1 100 LOAD CURRENT (mA) START-UP VOLTAGE (V) Without Diode With Diode NO-LOAD BATTERY CURRENT v.s. INPUT BATTERY VOLTAGE 100 120 140 160 0.5 1.5 2.5 INPUT BATTERY VOLTAGE (V) INPUT BATTERY CURRENT (uA)
Anachip Corp. Typical Performance Characteristics (Continued) EFFICIENCY vs. LOAD CURRENT 100 0.1 100 1000 LOAD CURRENT (mA) EFFICIENCY (%) VIN=1.2V VIN=2.4V SHUTDOWN CURRENT v.s. SUPPLY VOLTAGE -0.8 -0.6 -0.4 -0.2 0.2 0.4 0.6 0.8 SUPPLY VOLTAGE (V) SHUTDOWN CURRENT (uA) SHUTDOWN THRESHOLD VOLTAGE v.s. SUPPLY VOLTAGE 0.2 0.4 0.6 0.8 1.2 1.4 1.6 1.5 2.5 3.5 SUPPLY VOLTAGE (V) SHUTDOWN THRESHOLD VOLTAGE (V) Marking Information XX YM X XX : Identification code (See Appendix) Y : Year: 0-9 M : Month: A~L X : Blank: Normal L: Lead Free Package Appendix Part Number Package Identification Code AP1602A SOT89-5 EZ AP1602B SOT89-5 ET
Anachip Corp. Function Descriptions General Description AP1602 PFM (pulse frequency modulation) converter IC series combine a switch mode converter, power MOSFET, and precision voltage reference 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 (0.9V typ.). Designed to maximize battery life in portable products, and minimize switching losses by only switching as needed service the load. PFM converters 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. The SW on resistance is typically 1 to 1.5 W to minimize switch losses. When the output voltage drops, the error comparator enables 100KHz oscillator that turns on the MOSFET around 7.5us and 2.5ms off time. Turning on the MOSFET allows inductor current to ramp up, storing energy in a magnetic field and when MOSFET turns off that force 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 the second half each cycle. Depending on circuit, PFM converter can operate in either discontinuous mode or continuous conduction mode. Continuous conduction mode means that the inductor current does not ramp to zero during each cycle. Diode Selection Speed, forward drop, and leakage current are the three main considerations in selecting a rectifier diode. Best performance is obtained with Schottky rectifier diode, such as 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. Inductor Selection To operate as an efficient energy transfer element, the inductor must fulfill three requirements. 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 ON time. Second, the inductance must also be high enough so maximum current rating of AP1602 and inductor are not exceed at the other worst case condition of maximum input voltage and ON time. Lastly, the inductor must have sufficiently low DC 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. Capacitor Selection A poor choice for a output capacitor can result in poor efficiency and high output ripple. Ordinary aluminum electrolyzers, while inexpensive may have unacceptably poor ESR and ESL. There are low ESR aluminum capacitors for switch mode DC-DC converters which work much better than general propose unit. Tantalum capacitors provide still better performance at more expensive. OS-CON 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.
Anachip Corp. Package Information D C A I H G E B K J L F F Dimensions In Millimeters Dimensions In Inches Symbol Min. Nom. Max. Min. Nom. Max. A 4.40 4.50 4.60 0.173 0.177 0.181 B 4.05 4.15 4.25 0.159 0.163 0.167 C 1.50 1.60 1.70 0.059 0.063 0.067 D 1.30 1.40 1.50 0.051 0.055 0.059 E 2.40 2.50 2.60 0.094 0.098 0.102 F 0.80 0.031 G 3.00 Ref. 0.118 Ref. H 1.50 Ref. 0.059 Ref. I 0.40 0.46 0.52 0.016 0.018 0.020 J 1.40 1.50 1.60 0.055 0.059 0.063 K 0.35 0.39 0.43 0.014 0.015 0.017 L 5o Typ. 5o Typ.