Step-Up Synchronous PFM DC/DC Converter New Product Leaflet XC9140 Series mm Hg mm Hg Portable Gaming Bluetooth Equipment Wireless Mouse Blood Pressure Monitor The XC9140 series is a synchronous rectification type step-up DC/DC converter. The combination of PFM control and a CMOS structure achieves a low supply current, making these converters ideal for portable devices where battery life is a concern. Product startup is possible from an input voltage VIN=0.9V when the load current is 1mA and the output voltage is 3.3V, enabling these ICs to be used in devices that use one alkaline battery or one nickel-hydrogen battery. Two types are available: one that breaks continuity between the input and output using the load break function at shutdown, and one that maintains continuity between the input and output using the bypass mode function at shutdown. 1 Synchronous rectification improves efficiency The XC9140 series uses the synchronous rectification control method to reduce energy loss and improve efficiency compared to the previous XC9110 series. VIN=1.8V,VOUT=3.3V Efficiency : EFFI (%) 100 2 SOT-25 USP-6EL Improved load transient response characteristics The XC9140 series improves the load transient response to limit output voltage drops when the load current fluctuates. In addition, current control is used to control the coil current, enabling improvement of ripple voltage. XC9140A331, L=4.7μH, CIN=10μF, CL=20μF(ceramic) VOUT 80 20mV 50mA 60 IOUT=1mA XC9140A331 XC9110C331 40 0.1 1 10 100 Output Current : IOUT (mA) 3 Miniaturization is achieved XC9110/XC9111 L 5.3×5.8 The switching frequency is 1.2MHz, making it possible to use a small coil and ceramic capacitors. This enables mounting on an area that is approximately 74% smaller than previous products. XC9140 SD 1.2×1.6 L 2.0×1.6 CL 3528 size CIN 2012 size SOT-25 CL CIN 52.98mm2 ⇒ 13.88mm2 1608size SOT-25 Total component area Features 0.9V～5.5V Fixed Output Voltage Range 1.8V～5.0V (±2.0％), 0.1Ｖ Increments Output Current 100mA@VOUT=3.3V, VBAT=1.8V Driver Transistor Built-in 0.6Ω(N-ch Driver Tr.) Input Voltage Range Power Consumption 0.65Ω(P-ch Driver Tr.) 6.3μA(VBAT=VOUT+0.5V) High Speed Load Transient Response 20mV@VOUT=3.3V, VBAT=1.8V, IOUT=1→50mA 350mA PFM Switch Current Function Input bypass mode function or load break function UVLO Capacitor Ceramic Capacitor Compatible SOT-25, USP-6EL Packages www.torex.co.jp/english August 2012 ● Values shown in this sheet can be changed without any prior notice. New Product Leaflet Step-Up Synchronous PFM DC/DC Converter XC9140 Series 4 Bypass mode function Even when the step-up IC is not operating, the real-time clock (RTC) of the microcontroller in healthcare and other devices operates, and thus power must be supplied from a battery. To handle these types of applications, the bypass mode function is available in the XC9140 series as an option. In previous step-up DC/DC controllers (refer to Fig.1), the output voltage is lower than the input voltage by the amount of the forward voltage (VF) of the Schottky diode (SBD), resulting in lower efficiency. In bypass mode of the XC9140 series (refer to Fig.2), the output voltage is only lower than the input voltage by the amount due to the Pch driver ON-resistance (about 0.65Ω), the DC resistance component of the coil, and the load current, resulting in improved efficiency as shown in Fig.3. This is ideal for application devices where battery life is a concern. Bypass mode operates at shutdown in the C type. Fig.2 With Bypass Mode Fig.1 Previous Product Drop L VIN Battery SBD VOUT CIN CL Controller Low ON Resistance Micro Controller with RTC L VIN Battery CIN VOUT Controller Micro Controller with RTC CL Fig.3 Example of input-output voltage relationship in bypass mode VF V OUT (V) e od m ss BD lS ypa a b n h ter wit Ex 40 h t 1 i 9 Cw XC D / DC VIN (V) 5 Comparison of characteristics with previous products XC9140 XC9110/XC9111 XC9135 Non-synchronous (N-ch Built-in) Synchronous (N-ch,P-ch Built-in) Low ON Resistance 0.6Ω (N-ch), 0.65Ω (P-ch) 2.5Ω (N-ch) 0.2Ω (N-ch), 0.2Ω (P-ch) Control Method PFM PFM (2-step PFM：XC9111) PWM/PFM Auto (With PWM fixed control pin) Input Voltage Range 0.9V ~ 5.5V 0.9V ~ 10.0V 0.65V ~ 5.5V Operation Holding Voltage 0.7V 0.7V 0.65V Output Voltage Range (Accuracy) 1.8V ~ 5.0V (±2％) 1.5V ~ 7.0V (±2％) 1.8V ~ 5.0V (±2％) Oscillation Frequency 1.2MHz 100kHz, 180kHz 1.2MHz Power Consumption 6.3μA (TYP.) 2μA (TYP.) 37μA (TYP.) Protection Circuit Current Limit Lx Voltage Limit Function Load Disconnection, Input Bypass UVLO - Ceramic Capacitor Supported Not Supported Supported Package SOT-25 USP-6EL SOT-23, SOT-25 SOT-89, USP-6C USP-10B Circuit Configuration (internal driver) Synchronous (N-ch,P-ch Built-in) Current Limit Thermal Shutdown Load Disconnection, CL Discharge UVLO, FO (Error lamp) www.torex.co.jp/english August 2012 ● Values shown in this sheet can be changed without any prior notice.