HT7718B

HT77xxB 5V/100mA PFM Asynchronous Step-up Converter Features General Description • Low startup voltage: 0.85V (Typical) The HT77xxB 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, 3-pin SOT23 and 5-pin SOT23 The HT77xxB series consist of an oscillator, a PFM control circuit, a driver transistor, 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, 3-pin SOT23 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 D1: 1N5817 L1: 47μH~100μH (Coil Inductor) VIN LX VOUT OUT HT77xxB C1: 47μF OFF ON CE R1* GND C2: 22μF (Ceramic) * R1=0.15Ω is recommended to improve ripple performance Selection Table Part No. Output Voltage HT7718B 1.8V HT7722B 2.2V HT7727B 2.7V HT7730B 3.0V HT7733B 3.3V HT7737B 3.7V HT7750B 5.0V Packages SOT89 SOT23 SOT23-5 Markings 77xxB marking for SOT89 type 7xxB marking for SOT23 and SOT23-5 types Note: ″xx″ stands for output voltages. Rev. 1.20 1 September 13, 2018 HT77xxB Block Diagram OUT VREF LX LX Limiter 115kHz OSC Buffer PFM Control GND Chip Enable CE Pin Assignment SOT23 SOT89 SOT23-5 OUT LX GND 3 5 4 7xxB 77xxB 7xxB 1 2 1 2 GND LX CE OUT 3 NC 1 2 3 GND OUT LX Pin Description Pin No. Pin Name SOT89 SOT23 SOT23-5 — — 1 CE 2 3 2 OUT — — 3 NC 1 1 4 GND 3 2 5 LX Rev. 1.20 2 Pin Description Chip enable pin, high active. Output voltage pin No connection Ground pin Switching pin September 13, 2018 HT77xxB Absolute Maximum Ratings Parameter Value Unit OUT -0.3 to +6.0 V LX 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 500 SOT23-5 500 Maximum Junction Temperature Storage Temperature Range Lead Temperature (Soldering 10sec) ESD Susceptibility Junction-to-Ambient Thermal Resistance, θJA Power Dissipation, PD SOT89 0.625 SOT23 0.25 SOT23-5 0.25 ˚C/W W Recommended Operating Ratings Parameter VIN Operating Temperature Range Value 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. 1.20 3 September 13, 2018 HT77xxB Electrical Characteristics VIN=0.6×VOUT, IOUT=10mA and Ta=+25˚C, unless otherwise specified Test Condition Min. VIN Symbol Input Voltage Range Parameter — — — 5.5 V ∆VOUT Output Voltage Accuracy — -2.5 — +2.5 % VST Startup Voltage (Fig.1) VIN: 0V → 2V, IOUT=1mA — 0.85 1 V VHOLD Hold on Voltage (Fig.1) VIN: 2V → 0V, IOUT=1mA — — 0.7 V IIN No Load Input Current (Fig.1) IOUT=0mA 8 10 20 μA IDD Non-switching Current (Fig.2) VDD=VOUT+0.5V, VX=floating — 5 10 μA ISHDN Shutdown Current (Fig.1) CE=GND — 0.1 1 μA RDS(ON) On Resistance (Fig.3) Typ. Max. Unit VDD=1.7V, ILX=300mA VOUT=1.8V — 0.65 — VDD=2.1V, ILX=300mA VOUT=2.2V — 0.56 — VDD=2.6V, ILX=300mA VOUT=2.7V — 0.46 — VDD=2.9V, ILX=300mA VOUT=3.0V — 0.44 — VDD=3.2V, ILX=300mA VOUT=3.3V — 0.43 — VDD=3.6V, ILX=300mA VOUT=3.7V — 0.41 — VDD=4.85V, ILX=300mA VOUT=5.0V — 0.39 — Ω VIH CE High Threshold — 1.6 — — VIL CE Low Threshold — — — 0.4 V ILEAK LX Leakage Current (Fig.2) VDD=VX=VOUT+0.5V, measured at LX pin — — 1 μA fOSC Maximum Oscillator Frequency (Fig.2) VDD=0.9×VOUT, VX=5.5V, measured at LX pin — 115 — kHz DOSC Oscillator Duty Cycle (Fig.2) VDD=0.9×VOUT, VX=5.5V, measured at LX pin 65 75 85 % η Efficiency — 85 — % — V 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. D1: 1N5817 IIN VIN L1: 47μH (Coil Inductor) LX C1: 47μF (Ceramic) OUT VOUT C2: 22μF (Ceramic) HT77xxB CE GND Fig. 1 VX IX 1kΩ IDD LX OUT IDD HT77xxB GND ILX CE Fig. 2 Rev. 1.20 LX VDD OUT VDD HT77xxB GND CE Fig. 3 4 September 13, 2018 HT77xxB Typical Performance Characteristics VIN=0.6×VOUT, CIN=47µF, COUT=22µF, L=47µH, Ta=25˚C, unless otherwise specified HT7733B Efficiency vs. Output Current HT7750B Efficiency vs. Output Current HT7733B IDD vs. Ta HT7750B IDD vs. Ta HT7733B Startup/Hold-on Voltage HT7750B Startup/Hold-on Voltage RON vs. VDD Rev. 1.20 5 September 13, 2018 HT77xxB VIN=0.6×VOUT, CIN=47µF, COUT=22µF, L=47µH, Ta=25˚C, unless otherwise specified HT7733B Load Transient (1mA to 50mA) HT7750B Load Transient (1mA to 50mA) HT7733B Load Transient (1mA to 100mA) HT7750B Load Transient (1mA to 100mA) HT7733B Line Transient (1V to 2V, IOUT=50mA) HT7750B Line Transient (3V to 4V, IOUT=200mA) HT7733B Power ON/OFF (IOUT=50mA) HT7750B Power ON/OFF (IOUT=50mA) Rev. 1.20 6 September 13, 2018 HT77xxB VIN=0.6×VOUT, CIN=47µF, COUT=22µF, L=47µH, Ta=25˚C, unless otherwise specified HT7733B Operation (IOUT=0mA) HT7750B Operation (IOUT=0mA) HT7733B Operation (IOUT=100mA) HT7750B Operation (IOUT=100mA) HT7733B Chip Enable/Disable HT7750B Chip Enable/Disable Rev. 1.20 7 September 13, 2018 HT77xxB Component Selection PCB Layout Suggestion Power Inductor To reduce problems with conducted noise, there are some important points to note on the PCB layout. It is recommended to use a 47μH or higher inductance to remain low output ripple voltage in most applications. Increasing the inductance will result in lower output ripple voltage. It is suggested to choose a lower DCR with a typical value less than 1Ω to reduce the efficiency loss. Otherwise, the chosen inductor saturation current should be greater than its peak current with a typical value of 1A or higher in applications. • The input bypass capacitor must be placed close to the VIN pin. • The inductor, schottky diode and output capacitor trace should be as short as possible to reduce the conducted and radiated noise and increase overall efficiency. Schottky Diode The diode breakdown voltage rating should be higher than the maximum output voltage. The diode current rating equal to or greater than 1A is suggested. Input Capacitor A low ESR ceramic capacitor, CIN, is needed between the VIN and GND pins. Use ceramic capacitors with X5R or X7R dielectrics for their low ESRs and small temperature coefficients. For most applications, a 47µF capacitor will be a proper selection. SOT23/SOT23-5 PCB Layout Example Output Capacitor The output capacitor, COUT, selection is determined by the maximum allowable output voltage ripple. Use ceramic capacitors with X5R or X7R dielectrics for their low ESR characteristics. Capacitors in the range of 22μF to 100μF are a good starting point with an ESR of 0.1Ω or less. It is usually suggested to use a 22μF capacitor in most applications. Ripple Improved Resistor with a No Load Condition It is strongly recommended to add a ripple improved resistor, R1, to keep the switching stability with a no load condition. It is recommended to set R1 to 0.15Ω. Note that this extra resistor improves the ripple performance when in a no load condition, but induces higher ripple voltage when the load is heavy. SOT89 PCB Layout Example D1: 1N5817 L1: 47μH~100μH (Coil Inductor) VIN LX OUT HT77xxB C1: 47μF OFF ON CE GND VOUT R1* C2: 22μF (Ceramic) * R1=0.15Ω is recommended to improve ripple performance Rev. 1.20 8 September 13, 2018 HT77xxB Thermal Consideration For maximum operating rating conditions, the maximum junction temperature is 150˚C. However, it’s recommended that the maximum junction temperature does not exceed 125˚C during normal operation to maintain high reliability. The de-rating curve of the maximum power dissipation is show below: The maximum power dissipation depends upon the thermal resistance of the IC package, PCB layout, rate of surrounding airflow and difference between the junction and ambient temperature. The maximum power dissipation can be calculated by the following formula: PD(MAX) = (150˚C – 25˚C) / (500˚C/W) = 0.25W PD(MAX) = (TJ(MAX) – Ta) / θJA......................(W) For a fixed TJ(MAX) of 150˚C, the maximum power dissipation depends upon the operating ambient temperature and the package’s thermal resistance, θJA. The derating curve below shows the effect of rising ambient temperature on the maximum recommended power dissipation. Maximum Power Dissipation (W) Where TJ(MAX) is the maximum junction temperature, Ta is the ambient temperature and θJA is the junction to ambient thermal resistance. 1.0 0.8 SOT89 0.625 0.4 SOT23 SOT23-5 0.25 0 0 25 50 75 85 100 125 150 Ambient Temperature (oC) Rev. 1.20 9 September 13, 2018 HT77xxB Application Circuits Without CE Pin Application Circuits D1: 1N5817 L1: 47μH~100μH (Coil Inductor) VIN LX OUT VOUT HT77xxB C1: 47μF R1* GND C2: 22μF (Ceramic) * R1=0.15Ω is recommended to improve ripple performance With CE Pin Application Circuits D1: 1N5817 VIN L1: 47μH~100μH (Coil Inductor) LX OUT VOUT HT77xxB C1: 47μF OFF ON R1* CE GND C2: 22μF (Ceramic) * R1=0.15Ω is recommended to improve ripple performance Note: 1. When CE=‘0’, the device internal circuits such as the bandgap reference, gain block and all feedback and control circuitry will be switched off. 2. When CE=‘0’, the output voltage, VOUT, is almost equal to VIN. 3. If the CE pin is not used, it should be externally connected to the OUT pin. Rev. 1.20 10 September 13, 2018 HT77xxB Package Information Note that the package information provided here is for consultation purposes only. As this information may be updated at regular intervals users are reminded to consult the Holtek website for the latest version of the package information. Additional supplementary information with regard to packaging is listed below. Click on the relevant section to be transferred to the relevant website page. • Further Package Information (include Outline Dimensions, Product Tape and Reel Specifications) • Packing Meterials Information • Carton information Rev. 1.20 11 September 13, 2018 HT77xxB 3-pin SOT23 Outline Dimensions Symbol A Nom. Max. — — 0.057 A1 — — 0.006 A2 0.035 0.045 0.051 b 0.012 — 0.020 C 0.003 — 0.009 D — 0.114 BSC — E — 0.063 BSC — e — 0.037 BSC — e1 — 0.075 BSC — H — 0.110 BSC — L1 — 0.024 BSC — θ 0° — 8° Symbol A Rev. 1.20 Dimensions in inch Min. Dimensions in mm Min. Nom. Max. — — 1.45 A1 — — 0.15 A2 0.90 1.15 1.30 b 0.30 — 0.50 C 0.08 — 0.22 D — 2.90 BSC — E — 1.60 BSC — e — 0.95 BSC — e1 — 1.90 BSC — H — 2.80 BSC — L1 — 0.60 BSC — θ 0° — 8° 12 September 13, 2018 HT77xxB 5-pin SOT23 Outline Dimensions H Symbol A Nom. Max. — — 0.057 A1 — — 0.006 A2 0.035 0.045 0.051 b 0.012 — 0.020 C 0.003 — 0.009 D — 0.114 BSC — E — 0.063 BSC — e — 0.037 BSC — e1 — 0.075 BSC — H — 0.110 BSC — L1 — 0.024 BSC — θ 0° — 8° Symbol Rev. 1.20 Dimensions in inch Min. Dimensions in mm Min. Nom. Max. A — — 1.45 A1 — — 0.15 A2 0.90 1.15 1.30 b 0.30 — 0.50 C 0.08 — 0.22 D — 2.90 BSC — E — 1.60 BSC — e — 0.95 BSC — e1 — 1.90 BSC — H — 2.80 BSC — L1 — 0.60 BSC — θ 0° — 8° 13 September 13, 2018 HT77xxB 3-pin SOT89 Outline Dimensions          Symbol Dimensions in inch Min. Nom. Max. A 0.173 — 0.185 B 0.053 — 0.072 C 0.090 — 0.106 D 0.031 — 0.047 E 0.155 — 0.173 F 0.014 — 0.019 G 0.017 — 0.022 H — 0.059 BSC — I 0.055 — 0.063 J 0.014 — 0.017 Symbol Rev. 1.20  Dimensions in mm Min. Nom. Max. A 4.40 — 4.70 B 1.35 — 1.83 C 2.29 — 2.70 D 0.80 — 1.20 E 3.94 — 4.40 F 0.36 — 0.48 G 0.44 — 0.56 H — 1.50 BSC — I 1.40 — 1.60 J 0.35 — 0.44 14 September 13, 2018 HT77xxB Copyright© 2018 by HOLTEK SEMICONDUCTOR INC. The information appearing in this Data Sheet is believed to be accurate at the time of publication. However, Holtek assumes no responsibility arising from the use of the specifications described. The applications mentioned herein are used solely for the purpose of illustration and Holtek makes no warranty or representation that such applications will be suitable without further modification, nor recommends the use of its products for application that may present a risk to human life due to malfunction or otherwise. Holtek's products are not authorized for use as critical components in life support devices or systems. Holtek reserves the right to alter its products without prior notification. For the most up-to-date information, please visit our web site at http://www.holtek.com. Rev. 1.20 15 September 13, 2018