HT7750C

HT77xxC 5V PFM Asynchronous Step-up Controller Features General Description • Low startup voltage: 0.85V (Typical) The HT77xxC series is a set of PFM step-up DC/DC converters with high efficiency and low ripple. The series features extremely low start-up voltage and high output voltage accuracy. They require only few external components to provide a fixed output voltage of 1.8V, 2.2V, 2.7V, 3.0V, 3.3V, 3.7V and 5.0V. CMOS technology ensures low supply current and makes them ideal for battery-operated applications powered from one or more cells. • High efficiency up to 85% • Ultra low no load input current • High output voltage accuracy: ±2.5% • Fixed output voltage: 1.8V, 2.2V, 2.7V, 3.0V, 3.3V, 3.7V and 5.0V • Ultra low shutdown current: 0.1μA (Typical) • Package type: 3-pin SOT89 and 5-pin SOT23 The HT77xxC series consist of an oscillator, a PFM control circuit, a gate driver, a reference voltage unit and a high speed comparator. They employ pulse frequency modulation (PFM) for minimum supply current and ripple at light output loading. These devices are available in space saving 3-pin SOT89 and 5-pin SOT23 packages. For the 5-pin SOT23 package, it also contains a chip enable function to reduce power consumption during shutdown mode. Applications • One, two and three cell alkaline and NiMH/NiCd bettery powered portable products • Portable equipment/handheld devices Typical Application Circuits L1: 47μH~100μH (Coil Inductor) D1: 1N5817 VIN C1: 47μF (Ceramic) Cb: 10nF OUT Rb: 300Ω ZXTN25020CFH OFF VOUT HT77xxC R1* EXT CE ON * R1=0.15Ω is recommended to improve ripple performance GND C2: 22μF (Ceramic) Selection Table Part No. Output Voltage HT7718C 1.8V HT7722C 2.2V HT7727C 2.7V HT7730C 3.0V HT7733C 3.3V HT7737C 3.7V HT7750C 5.0V Packages SOT89 SOT23-5 Markings 77xxC marking for SOT89 type 7xxC marking for SOT23-5 type Note: ″xx″ stands for output voltages. Rev. 1.10 1 August 01, 2018 HT77xxC Block Diagram VREF EXT Gate Driver 115kHz OSC Buffer PFM Control GND OUT Chip Enable CE Pin Assignment SOT89 SOT23-5 EXT GND 5 4 77xxC 7xxC 1 2 CE OUT 3 NC 1 2 3 GND OUT EXT Pin Description Pin No. Pin Name Pin Description SOT89 SOT23-5 — 1 CE 2 2 OUT — 3 NC 1 4 GND Ground pin 3 5 EXT Gate driver output pin Rev. 1.10 Chip enable pin, high active. Output voltage pin No connection 2 August 01, 2018 HT77xxC Absolute Maximum Ratings Parameter Value Unit OUT -0.3 to +6.0 V EXT and CE -0.3 to +6.0 V +150 ˚C -65 to +150 ˚C +260 ˚C Human Body Mode 5000 V Machine Mode 400 V SOT89 200 SOT23-5 500 Maximum Junction Temperature Storage Temperature Range Lead Temperature (Soldering 10sec) ESD Susceptibility Junction-to-Ambient Thermal Resistance, θJA Power Dissipation, PD ˚C/W SOT89 0.625 SOT23-5 0.25 W Recommended Operating Ratings Parameter Value VIN Operating Temperature Range Unit 0.85 to 5 V -40 to +85 ˚C Note that Absolute Maximum Ratings indicate limitations beyond which damage to the device may occur. Recommended Operating Ratings indicate conditions for which the devices are intended to be functional, but do not guarantee specified performance limits. Rev. 1.10 3 August 01, 2018 HT77xxC Electrical Characteristics VIN=0.6×VOUT, IOUT=10mA and Ta=+25˚C, unless otherwise specified Symbol Parameter Test Condition Min Typ Max Unit — — — 5.5 V — -2.5 — +2.5 % — 0.85 1 V VIN: 2V → 0V, IOUT=1mA — — 0.7 V No Load Input Current (Fig.1) IOUT=0mA 8 10 20 μA IDD Non-switching Current (Fig.2) VDD=VOUT+0.5V — 5 10 μA ISHDN Shutdown Current (Fig.1) CE=GND — 0.1 1 μA VIN Input Voltage Range ∆VOUT Output Voltage Accuracy VST Startup Voltage (Fig.1) VIN: 0V → 2V, IOUT=1mA VHOLD Hold on Voltage (Fig.1) IIN RP(ON) High Side On Resistance (Fig.3) RN(ON) Low Side On Resistance (Fig.3) VDD=1.7V, IEXT=10mA VOUT=1.8V — 46 — VDD=3.2V, IEXT=10mA VOUT=3.3V — 37 — VDD=4.85V, IEXT=10mA VOUT=5.0V — 30 — VDD=1.7V, IEXT=-10mA VOUT=1.8V — 25 — VDD=3.2V, IEXT=-10mA VOUT=3.3V — 17 — VDD=4.85V, IEXT=-10mA VOUT=5.0V — 15 — Ω Ω VIH CE High Threshold — 1.6 — — VIL CE Low Threshold — — — 0.4 V V fOSC Maximum Oscillator Frequency (Fig.2) VDD=0.9×VOUT, measured at EXT pin — 115 — kHz DOSC Oscillator Duty Cycle (Fig.2) VDD=0.9×VOUT, measured at EXT pin 65 75 85 % η Efficiency — — 85 — % Note: Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the devices are intended to be functional, but do not guarantee specific performance limits. The guaranteed specifications apply only for the test conditions listed. L1: 47μ (Coil Inductor) IIN D1: 1N5817 VIN C1: 47μF (Ceramic) Cb: 10nF Rb: 300Ω ZXTN25020CFH VOUT OUT EXT HT77xxC C2: 22μF (Ceramic) CE GND Fig. 1 IDD IDD EXT OUT V(EXT) VDD GND CE GND Fig. 2 Rev. 1.10 OUT VDD HT77xxC HT77xxC IEXT EXT CE Fig. 3 4 August 01, 2018 HT77xxC Typical Performance Characteristics VIN=0.6×VOUT, CIN=47µF, COUT=22µF, L=47µH, Ta=25˚C, unless otherwise noted HT7733C Efficiency vs. Output Current HT7750C Efficiency vs. Output Current HT7733C IDD vs. Ta HT7750C IDD vs. Ta HT7733C Startup/Hold-on Voltage HT7750C Startup/Hold-on Voltage RP vs. VDD RN vs. VDD Rev. 1.10 5 August 01, 2018 HT77xxC VIN=0.6×VOUT, CIN=47µF, COUT=22µF, L=47µH, Ta=25˚C, unless otherwise noted HT7733C Load Transient (1mA to 50mA) HT7750C Load Transient (1mA to 50mA) HT7733C Load Transient (1mA to 100mA) HT7750C Load Transient (1mA to 100mA) HT7733C Line Transient (1V to 2V, IOUT=50mA) HT7750C Line Transient (3V to 4V, IOUT=100mA) HT7733C Power ON/OFF (IOUT=50mA) HT7750C Power ON/OFF (IOUT=50mA) Rev. 1.10 6 August 01, 2018 HT77xxC VIN=0.6×VOUT, CIN=47µF, COUT=22µF, L=47µH, Ta=25˚C, unless otherwise noted HT7733C Operation (IOUT=0mA) HT7750C Operation (IOUT=0mA) HT7733C Operation (IOUT=100mA) HT7750C Operation (IOUT=100mA) HT7733C Chip Enable/Disable HT7750C Chip Enable/Disable Rev. 1.10 7 August 01, 2018 HT77xxC Component Selection External Power Elements Lower R DS(ON) of power elements gain better transferred efficiency. It’s recommended to use ZXMN2B14FH or AFN2306A for the external MOSFETs and ZXTN25020CFH for the external Bipolar Junction Transistor. Power Inductor It’s recommended to use a 47μH or higher inductance to remain low output ripple voltage in most applications. Increasing the inductance gains lower output ripple voltage. It is suggested that to choose lower DCR to reduce the efficiency loss, typically DCR