iC-DC 2-CHANNEL BUCK/BOOST DC/DC CONVERTER iC-DC is a monolithic switching converter with two back-end linear regulators. The output voltages of the two linear regulators can be individually pinconfigured within a range of 1.5 V to 5.5 V. The switching converter supplies up to 300 mA which can be drawn from the two linear regulators in the ratio required. The high efficiency of the buck/boost converter for an input voltage range of 4 V to 36 V makes iC-DC suitable for industrial applications. Using very few external components, a DC/DC power pack can be created with a stabilized supply voltage and minimum power dissipation. Applications • • Dual voltage supply by buck/boost converters with adjustable, back-end linear regulators Power management for laser, encoder and automotive applications Features • • • • • • • • • • • • • Wide input voltage range of 4 V to 36 V Reverse polarity protection up to -36 V with autarky Universal buck/boost converter with high efficiency Two back-end, adjustable linear regulators (1.5 V to 5.5 V) with a total of up to 300 mA of output current and a separate output voltage monitor Low residual ripple with small capacitors in the μF range Separate enable inputs for the linear regulators Two switched linear regulator outputs Integrated switching transistors and flyback diodes Integrated 3 MHz oscillator with no external components Active noise spectrum reduction Error messaging with overtemperature, overvoltage, and undervoltage at the current-limited open-collector output Wide temperature range of -40 °C to 125 °C Space saving 24-pin QFN package % # !# # # # # # !" $ Am Kuemmerling 18 • D -55294 Bodenheim, Germany Phone: +49 (6135) 9292-300 • Fax: +49 (6135) 9292-192 • http://www.ichaus.com # iC-DC 2-CHANNEL BUCK/BOOST DC/DC CONVERTER The chip temperature, input voltage, and integrated reverse polarity protection are monitored and errors signaled by current-limited open-collector outputs. With overtemperature the switching converter is disabled to reduce the chip’s power dissipation. Pin Configuration QFN24 4x4 mm² 24 23 22 21 20 19 1 2 3 4 5 6 The linear regulator output voltages are monitored and once having reached the steady state they are also switched to outputs POE1 and POE2. The output voltages of the two linear regulators VCC1 and VCC2 can be switched on and off by enable inputs ENV1 and ENV2. DC ... yyww... The device’s standby function can be activated to minimize the current consumption. Key Specifications 7 8 9 10 11 12 Pin Functions General Supply Voltage Range 18 17 16 15 14 13 +4 V to +36 V No. Name Function 1 RREF Reference Resistor 2 GNDA Analog Ground Quiescent Current VB VB = 24 V VB = 12 V VB = 4 V typ. 4 mA typ. 7 mA typ. 25 mA 3 CFG1 VCC1 Configuration 3.3/5.0 V or 1.5 V to 5.5 V with ext. R Divider Operating Current VB VB = 24 V, 5V/100 mA each VB = 12 V, 5V/100 mA each VB = 4 V, 5V/30 mA each 4 CFG2 typ. 70 mA typ. 150 mA typ. 150 mA VCC2 Configuration 2.5/3.3 V or 1.5 V to 5.5 V with ext. R Divider 5 TEST Test Input 6 POE2 Power Output Enable VCC2 Voltage Standby Current typ. 100 µA @ 24 V 7 V2OK Error Output VCC2 Voltage Thermal Shutdown Threshold typ. 160 °C 8 VCC2 1.5 V to 5.5 V Linear Regulator Output 2 ESD Susceptibility 2 kV (HBM 100 pF, 1.5 kΩ) 9 VH2 Intermediate Voltage 2 for VCC2 Regulator Operational Temperature -40 °C to +125 °C 10 VH1 Intermediate Voltage 1 for VCC1 Regulator Package (RoHS compliant) QFN24 (4.0 mm x 4.0 mm) 11 VCC1 1.5 V to 5.5 V Linear Regulator Output 1 12 V1OK Error Output VCC1 Voltage Switching Regulators (x = 1, 2) 13 POE1 Power Output Enable VCC1 Voltage Voltage at VH typ. 7.75 V 14 VH Intermediate Voltage typ. VCCx + 400 mV 15 VHL Inductor Terminal VH typ. 22 µH, 1 A 16 GND Power Ground 17 VBL Inductor Terminal VB 18 VBR Reverse Protected Supply Voltage 19 VB +4 V to +36 V Supply Voltage 20 ENV1 VCC1 Linear Regulator Activation 21 ENV2 VCC2 Linear Regulator Activation 22 VBROK Error Output Supply Voltage 23 TOK Error Output Overtemperature 24 NAUT Error Output Autarky TP Thermal Pad Voltage at VHx Inductor LVBH Internal Oscillator RREF 20 kΩ ± 1% Linear Regulator (x = 1, 2) Output Voltage Range 1.5 V to 5.5 V Output Voltage VCC1 (CFG1 = VCC1) (CFG1 = GNDA) 5.0 V ± 5% 3.3 V ± 5% Output Voltage VCC2 (CFG2 = VCC2) (CFG2 = GNDA) 3.3 V ± 5% 2.5 V ± 5% Output Ripple 10 mVpp @ 100 mA Total Load Current 300 mA max. Switch Output POEx VCCx @ 5 mA Voltage Monitoring (x = 1, 2) Undervoltage Threshold 92 % of VCCx Overvoltage Threshold 108 % of VCCx This preliminary information is not tantamount to a guarantee of device characteristics. All rights to technical changes reserved. Am Kuemmerling 18 • D -55294 Bodenheim, Germany Phone: +49 (6135) 9292-300 • Fax: +49 (6135) 9292-192 • http://www.ichaus.com Rev. 1.0