UNISONIC TECHNOLOGIES CO., LTD UC5301 Preliminary CMOS IC SWITCHED-CAPACITOR VOLTAGE INVERTERS DESCRIPTION The UTC UC5301 is an unregulated charge-pump voltage inverter. It can be used to generate a negative supply from positive input. Input voltages varying from +1.8V to +5V can be inverted into a -1.8V ~ -5V output supply. The device can be operated on a 0.45mA typical current from supplies 3.3V, which meets the requirements of battery-powered and board level voltage conversion applications. The UTC UC5301 can deliver 25mA output current with a voltage drop of 250mV. The parts are over-temperature protected. The UTC UC5301 is generally used in cell phones, PDAS, and other portable equipments, small LCD panels, handy-terminals. FEATURES * Operating voltage range: 1.8V ~ 5V * Inverts input supply voltage * 25mA output current with a voltage drop of 250mV * Quiescent current 0.45mA from supplis 3.3V * Voltage conversion efficiency up to 99% * Only two capacitors needed * Over-temperature circuit * 2KV ESD rating ORDERING INFORMATION Ordering Number Lead Free UC5301L-S08-R UC5301L-S08-R Halogen Free UC5301G-S08-R Package Packing SOP-8 Tape Reel (1)Packing Type (1) R: Tape Reel (2)Package Type (2) S08: SOP-8 (3)Lead Free (3) G: Halogen Free, L:Lead Free www.unisonic.com.tw Copyright © 2011 Unisonic Technologies Co., Ltd 1 of 6 QW-R502-602.a UC5301 Preliminary PIN CONFIGURATION PIN DESCRIPTION PIN NO. 1,6,7 2 3 4 5 8 PIN NAME NC CP+ GND CPOUT IN CMOS IC DESCRIPTION Not Internally Connected Flying Capacitor’s Positive Terminal Ground Flying Capacitor’s Negative Terminal Inverting Charge-Pump Output Power-Supply Positive Voltage Input BLOCK DIAGRAM UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 6 QW-R502-602.a UC5301 Preliminary CMOS IC ABSOLUTE MAXIMUM RATING (TA=25°C unless otherwise specified.) PARAMETER SYMBOL RATINGS UNIT IN to GND Voltage VIN -0.3V ~ +5.5V V OUT to GND Voltage VOUT -5.5V ~ +0.3V V C1+ to GND Voltage VC+ -0.3V ~ (VIN+0.3V) V C1- to GND Voltage VC(VOUT -0.3V) ~ +0.3V V OUT Output Current IOUT 100mA mA Operating Temperature TOPR -40°C ~ 85°C °C OUT Short Circuit to GND Indifinite Storage Temperature TS -65°C ~ 150°C °C Junction Temperature TJ 150°C °C Reflow Temperature (Soldering, 10sec) 260°C °C ESD Rating HBM VESD 2000V V Notes: 1.Absolute maximum ratings are those values beyond which the device could be permanently damaged. 1.Absolute maximum ratings are stress ratings only and functional device operation is not implied. 2.Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. THERMAL DATA PARAMETER Junction to Ambient SYMBOL θJA RATINGS 160 UNIT °C/W ELECTRICAL CHARACTERISTICS (VIN=+3.3V/5.0V, C1 = C2 = C3= 1µF, TA= -40 ~ 85°C unless otherwise specified. Typical values is at TA=25°C.) PARAMETER Input Voltage SYMBOL VIN TEST CONDITIONS MIN TYP RLOAD=10kΩ 1.8 VIN=+3.3V TA=25°C 0.42 Supply Current IQ VIN=+5.0V TA=25°C 0.9 VIN=3.3V 252 295 Charge Pump Frequency FSW 290 VIN=5.0V VIN=3.3V ILOAD=5mA 8.3 Output Resistance(Note) ROUT VIN=5.0V ILOAD=5mA 8.8 VIN=3.3V ILOAD=5mA 13 VIN=3.3V ILOAD=25mA 55 Output Ripple VRIPPLE VIN=5.0V ILOAD=5mA 23 VIN=5.0V ILOAD=25mA 96 Voltage Conversion Efficiency VIN=3.3V/5.0V No Load 99 VIN=3.3V ILOAD=5mA 93 Power Efficiency 90 VIN=5.0V ILOAD=10mA Note: Capacitor contribution (ESR component plus (1/FSW)・C) is approximately 20% of output. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw MAX 5 0.5 330 9.6 UNIT V mA kHz Ω mV P-P % % % 3 of 6 QW-R502-602.a UC5301 Preliminary CMOS IC DETAILED DESCRIPTION Four switches (S1, S2, S3, and S4) incorporated in the device, which are switched in a sequence to inverter the input supply voltage. The external capacitors determine the energy transfer and storage. The course of voltage conversion is show in Figure. 1. When S1 and S3 are closed, C1 charges to the supply voltage VIN. During this time interval, switches S2 and S4 are open. In the second time interval, S1 and S3 are open; at the same time, S2 and S4 are closed, C1 is charging C2. After a number of cycles, the voltage across C2 will be pumped to VIN. Since the anode of C2 is connected to ground, the output at the cathode of C2 equals - (VIN) under o load current condition. The UTC UC5301 is mainly to generate a negative supply voltage. The input supply voltage is varying from1.8V to 5V. The output characteristics of this circuit can be approximated by an ideal voltage source in series with a resistance. The voltage source equals - (VIN). The output resistance, ROUT, is a function of the ON resistance of the internal MOSFET switches, the oscillator frequency, the capacitance and the ESR of both C1 and C2. Since the switching current charging and discharging C1 is approximately twice as the output current, the effect of the ESR of the pumping capacitor C1 will be multiplied by four in the output resistance. The output capacitor C2 is charging and discharging at a current approximately equal to the output current, therefore, this ESR term only counts once in the output resistance. The value of ROUT is approximately calculated in the following equation: 2 R OUT ≅ 2R SW + + 4ESR C1 + ESR C2 f OSC × C1 (RSW is the sum of the ON resistance of the internal MOSFET switches shown in Figure 1.) Lower output resistance is dependent on higher capacitance and lower ESR capacitors. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 4 of 6 QW-R502-602.a UC5301 Preliminary CMOS IC APPLICATION INFORMATION Table 1. Low-ESR Capacitor Manufacturers PRODUCTION METHOD Surface-Mount Ceramic MANUFACTURER AVX Matsuo SERIES X7R X7R Capacitor Selection Proper selection of external capacitor in applications is critical to keep the lowest output resistance; the capacitors should be with low ESR (Table 1). Minimizing the charge-pump capacitor’s ESR minimizes the total output resistance because the charge-pump output resistance is a function of C1’s and C2’s ESR. Flying Capacitor (C1) Increasing the flying capacitor’s value reduces the output resistance. Above a certain point, increasing C1’s capacitance has a negligible effect because the output resistance becomes dominated by the internal switch resistance and capacitor ESR. Output Capacitor (C2) Increasing the output capacitor’s value reduces the output ripple voltage. Decreasing its ESR reduces both output resistance and ripple. Lower capacitance values can be used with light loads if higher output ripple can be tolerated. The peak-to-peak ripple is determined by the following equations: IL VRIPLE = + 2XIL +ESRC2 fOSC × C2 The output voltage drop is the load current times the output resistance, and the power efficiency is calculated as: 2 η= POUT IL RL = 2 2 PIN IL RL + IL ROUT + IQ (VIN ) (IQ(VIN) is the quiescent power loss of the IC device, and IL2ROUT is the conversion loss associated with the switch on-resistance, the two external capacitors and their ESRS.) Input Bypass Capacitor (C3) Input bypass capacitor is used to bypass the incoming supply to reduce its AC impedance and the impact of the UTC UC5301’s switching noise. The value of a bypass capacitor is recommended to be equal to the C1. Voltage Inverter The device is mainly for application as a charge-pump voltage inverter (Figure 2). Less external capacitors are required. (C1, C2 and a bypass capacitor, if necessary.) Layout and Grounding For a better noise performance, a good layout is necessary. Therefore, it’s best to mount all components as close together as possible, keep traces short to minimize parasitic inductance and capacitance and use a ground plane. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 5 of 6 QW-R502-602.a UC5301 Preliminary TYPICAL OPERATING CIRCUIT TYPICAL APPLICATION CIRCUIT CMOS IC UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 6 of 6 QW-R502-602.a