HP4555D8-42

HP4555 High Input Voltage Charger with OVP Protection and Charge Termination GENERAL DESCRIPTION FEATURES ⚫ The HP4555 is a cost-effective, fully integrated high input voltage single-cell Li-ion battery charger. The charger uses a CC/CV charge profile required by Li-ion battery. The charger accepts an input voltage up to 24V but is disabled when the input voltage exceeds the OVP threshold, typically 6.8V, to prevent excessive power dissipation. The 24V rating eliminates the over-voltage protection circuit required in a low input voltage charger. The charge current and the end-of-charge (EOC) current are programmable with external resistors. When the battery voltage is lower than 2.55V, the charger preconditions the battery with typically 20% of the programmed charge current. When the charge current reduces to the programmable EOC current level during the CV charge phase, the charging process is terminated, and meanwhile an EOC ̅̅̅̅̅̅ pin, which is an indication is provided by the 𝐶𝐻𝐺 open-drain output. An internal thermal foldback function protects the charger from any thermal ̅̅̅̅̅̅ ) allow ̅̅̅̅̅̅ and 𝐶𝐻𝐺 failure. Two indication pins ( 𝑃𝑃𝑅 simple interface to a microprocessor or LEDs. When no adapter attached, the charger draws less than 1μA leakage current from the battery. The HP4555 is available in Green DFN-2×2-8L ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ Complete Charger for Single-Cell-Li-ion or Polymer Batteries Integrated Pass Element and Current Sensor No External Blocking Diode Required Low Component Count and Cost Programmable Charger Current Programmable End-of-Charger Current Charge termination when charge current reduces to EOC Current Charger Current Thermal Foldback for Thermal Protection 2.55V Trickle Charge Threshold 6.8V Input Over-Voltage Protection 24V Maximum Voltage for the Power Input Power Presence and Charge Indications Less than 1μA Leakage Current from the Battery When No Input Power Attached Less than 200uA Supply Current when Charging is terminated Available in Green DFN-2x2-8L Packages APPLICATIONS packages and is rated between -40 ℃ to +85 ℃ temperature range. ⚫ ⚫ ⚫ ⚫ ⚫ Mobile Phones Blue-Tooth Devices PDAs MP3 Players Stand-Alone Chargers ⚫ Other Handheld Devices PIN ASSIGNMENT HP4555(TOP VIEW) 1 8 2 7 3 GND VIN PPR CHG EN 4 6 5 BAT IREF IMIN GND DFN-2x2-8L HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. Page 1 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination ORDER INFORMATION PART NO PACAKGE TEMPERATURE TAPE & REEL HP4555D8-42 DFN-2x2-8L -40 ~ +85℃ 4000/REEL HP4555D8-43 DFN-2x2-8L -40 ~ +85℃ 4000/REEL HP4555D8-435 DFN-2x2-8L -40 ~ +85℃ 4000/REEL HP4555D8-44 DFN-2x2-8L -40 ~ +85℃ 4000/REEL PART NUMBER RULES MARKING DESCRIPTION: HP4555□ 1 -□ 2 Code Description 1 □ Package: DFN-2x2-8L XXXX XYWV D8: DFN-2x2-8L 2 □ Charge voltage: 42/43/435/44: charge Battery voltage “XXXX”: Part number, here is “4555”. are “XYWV”: “X” stands for Internal Control Code, “Y” 4.2V/4.3V/4.35V/4.4V stands for Internal Control Code, “W” stands for the week of manufacturing, “V” stands for charge voltage. TYPICAL APPLICATION CIRCUIT VIN BAT C1 IREF ON RIMIN CHG VIN BAT C1 R1 LED1 R2 LED2 OFF ON GND Figure 1.Typical application circuit interfacing to indication LEDs Component Description for Figure 1 IREF C2 PPR EN TO INPUT HP4555 HP4555 OFF IMIN TO BATTREY RIREF IMIN TO BATTREY RIREF C2 VCC RIMIN R1 R2 TO MCU TO INPUT CHG PPR EN GND Figure 2.Typical application circuit with the indication signals interfacing to an MCU Component Description for Figure 2 PART DESCRIPTION PART DESCRIPTION C1, C2 1μF X5R ceramic cap C1, C2 1μF X5R ceramic cap RIREF 24KΩ,1% for 500mA charge current RIREF 24KΩ,1% for 500mA charge current RIMIN 270KΩ,1% for 40mA EOC current RIMIN 270KΩ,1% for 40mA EOC current R1, R2 1KΩ, 5% R1, R2 100KΩ,5% HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. Page 2 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination PIN DESCRIPTION PIN NO SYMBOL 1 VIN 2 ̅̅̅̅̅̅ 𝑃𝑃𝑅 3 ̅̅̅̅̅̅ 𝐶𝐻𝐺 4 ̅̅̅̅ 𝐸𝑁 5 GND 6 IMIN 7 IREF 8 BAT FUNCTION Power Input. A 1μF or larger value X5R ceramic capacitor is recommended to be placed as close as possible to the input pin for decoupling purpose. Additional capacitance may be required to provide a stable input voltage. Open-drain Power Presence Indication. The open-drain MOSFET turns on when the input voltage is above the POR threshold but below the OVP threshold, and turns off otherwise. This pin is capable of sinking 15mA (MIN) current to drive an LED. The maximum voltage rating for this pin is 5.5V. This ̅̅̅̅ pin input. pin is independent on the 𝐸𝑁 Open-drain Charge Indication. This pin outputs a logic low when a charge cycle starts and turns to high impedance when the end-of-charge (EOC) condition is qualified. This pin is able to sink 15mA (MIN) current to drive an LED. When the charger is disabled, the ̅̅̅̅̅̅ 𝐶𝐻𝐺 pin outputs high impedance. Enable Input. This is a logic input pin to disable or enable the charger. Drive high to disable the charger. When this pin is driven to low or left floating, the charger is enabled. This pin has an internal 200kΩ pull-down resistor. System Ground. End-of-Charge (EOC) Current Programming Pin. Connect a resistor between this pin and the GND pin to set the EOC current. The EOC current IMIN can be programmed by the following equation: 9700 𝐼𝑀𝐼𝑁 = + 4 (𝑚𝐴) 𝑅𝐼𝑀𝐼𝑁 where RIMIN is in kΩ. The programmable range covers from 5mA to 120mA. EOC current will be influenced by battery internal impedance and results in a small drift. When programmed to less than 5mA, the accuracy is not guaranteed. Charge-Current Programming and Monitoring Pin. Connect a resistor between this pin and the GND pin to set the charge current limit determined by the following equation: 12000 𝐼𝑅𝐸𝐹 = (𝑚𝐴) 𝑅𝐼𝑅𝐸𝐹 where RIREF is in kΩ. The resistor should be placed very close to this pin. The IREF pin voltage also monitors the actual charge current during the entire charge cycle, including the trickle, constantcurrent, and constant-voltage phases. When disabled, VIREF = 0V. Charger Output Pin. Connect this pin to the battery. A 1μF or larger X5R ceramic capacitor is ̅̅̅̅ pin is pulled to logic high, the recommended for decoupling and stability purposes. When the 𝐸𝑁 BAT output is disabled. ABSOLUTE MAXIMUM RATINGS (Note) SYMBOL VIN RθJA ITEMS VALUE UNIT Input Voltage -0.3~27 V Voltage of other PINs -0.3~6 V 118 ℃/W Thermal Resistance DFN-2x2-8L TJ Junction Temperature 150 ℃ TSTG Storage Temperature -65 ~ +150 ℃ Package Lead Soldering Temperature (10s) 260 ℃ ESD MM Machine Mode 200 V ESD HBM Human Body Mode 8 KV TSOLDER Note: Exceed these limits to damage to the device. Exposure to absolute maximum rating conditions may affect device reliability. HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. Page 3 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination RECOMMANDED OPERATING RANGE SYMBOL ITEMS VALUE UNIT VMAX Maximum Supply Voltage ≤24 V VIN Operating Supply Voltage 4.55 to 6.10 V IREF Programmed Charge Current 20 to 700 mA TOPT Operating Temperature -40 to +85 ℃ TYPICAL CHARGE PROFILE Trickle CC CV EOC Recharge CV 4.2V IREF 4.05V 75% IREF Charge Voltage 2.55V 20% IREF Charge Current IMIN CHG indication CHG Time Figure 3. Typical Charge Profile HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. Page 4 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination ELECTRICAL CHARACTERISTICS VIN=5V, RIMIN=243KΩ, TA=25℃, unless otherwise noted. SYMBOL ITEMS CONDITIONS MIN TYP MAX UNIT Power-ON Reset VPOR Rising POR Threshold ̅̅̅̅̅̅ to VBAT=3.0V, RIREF=120KΩ, use 𝑃𝑃𝑅 3.4 3.9 4.2 V VPOR Falling POR Threshold indicate the comparator output. 3.1 3.6 3.9 V 100 150 mV VIN-VBAT Offset Voltage VOS Rising Edge VOS Falling Edge ̅̅̅̅̅̅ to VBAT=4.5V, RIREF=120KΩ, use 𝑃𝑃𝑅 indicate the comparator output.(1) 10 80 mV ̅̅̅̅̅̅ to VBAT=4.5V, RIREF=120KΩ, use 𝑃𝑃𝑅 6.5 6.80 7.1 V indicate the comparator output. 170 250 300 mV Over-Voltage Protection VOVP OVP Threshold VOVPHYS OVP Threshold Hysteresis Standby Current IVINSTD IBATSTD standby Mode VIN Pin Current ̅̅̅̅ = L, RIREF=120KΩ VIN=5V, VBAT=4.5V, 𝐸𝑁 135 200 μA Standby Mode BAT Pin Current ̅̅̅̅ = L, RIREF=120KΩ VIN=5V, VBAT=4.5V, 𝐸𝑁 1.7 2 μA 200 μA Shutdown Current IVINDIS Shutdown Mode VIN Pin Current VIN=5V, RIREF=120KΩ, Charger disabled 130 IVINASD Shutdown Mode VIN Pin Current VBAT=4.5V, VIN=4.3V 92 μA IBATASD Shutdown Mode BAT Pin Current VBAT=4.5V, VIN=4.3V 1.8 μA IVINUVLO UVLO Mode Supply Current VIN=VBAT=3.6V 88 μA IBATUVLO UVLO Mode BAT Pin Current VIN=VBAT=3.6V 1 μA Sleep Current IBATSLEEP BAT Pin Current Input is floating or 0V 1 μA Voltage Regulation VOUT Output Voltage RDS(ON) ΔVRECHRG Charge Current PMOS On Resistance Auto Recharge Battery Voltage RIMIN=2MΩ, charge current=20mA 4.158 4.2 4.242 4.257 4.3 4.343 4.306 4.35 4.394 4.356 4.4 4.444 VBAT=3.8V, charge current=500mA, 1.2 RIREF=10KΩ VOUT – VBAT 100 150 V Ω 200 mV (2) VIREF IREF Pin Output Voltage VBAT=3.8V, RIREF=120KΩ 1.218 V IREF Constant Charge Current RIREF=120KΩ, VBAT=2.8V to 3.8V 90 100 110 mA ITRK Trickle Charge Current RIREF=120KΩ, VBAT=2.4V 13 22 31 mA IMIN End-of-Charge Current RIMIN=243KΩ 22 44 66 mA RIMIN=2MΩ 4 9 14 mA 2.45 2.55 2.65 V Preconditioning Charge Threshold VMIN Preconditioning Charge Threshold Voltage HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. RIREF=24.3KΩ Page 5 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination VMINHYS Preconditioning Voltage Hysteresis RIREF=24.3KΩ 70 100 130 mV Internal Temperature Monitoring TFOLD Charge Current Foldback Threshold ℃ 115 Logic input and outputs VEN_H ̅̅̅̅ Pin Logic Input High 𝐸𝑁 VEN_L ̅̅̅̅ Pin Logic Input Low 𝐸𝑁 REN ICHG_sink ICHG_leakage IPPR_sink IPPR_leakage 1.5 ̅̅̅̅ Pin Internal Pull Down 𝐸𝑁 Resistance ̅̅̅̅̅̅ 𝐶𝐻𝐺 Sink Current when LOW ̅̅̅̅̅̅ 𝐶𝐻𝐺 Leakage Current when High Impedance ̅̅̅̅̅̅ Sink Current when LOW 𝑃𝑃𝑅 ̅̅̅̅̅̅ Leakage Current when High 𝑃𝑃𝑅 Impedance Pin Voltage = 1V V 150 200 10 18 VCHG = 5.5V Pin Voltage = 1V 0.8 V 250 KΩ mA 20 10 18 VPPR = 5.5V μA mA 20 μA Note: ̅̅̅̅̅̅ output can be used as the indication for the offset comparator output indication. If the V BAT is 1. The 4.5V VBAT is selected so that the 𝑃𝑃𝑅 lower than the POR threshold, no output pin can be used for indication. 2. The charge current can be affected by the thermal foldback function if the IC under the test setup cannot dissipate the heat. HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. Page 6 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination TYPICAL PERFORMANCE CHARACTERISTICS VIREF vs IBAT VOUT vs VIN 1.4 4.3 1.2 1 VIREF(V) VOUT(V) 4.25 4.2 0.8 0.6 0.4 4.15 0.2 4.1 0 4.5 5 5.5 6 6.5 0 100 200 VIN(V) IBAT vs VIN 600 VBAT(V) IBAT(mA) 4.2 BAT=3.8V 300 200 3.2 0 3 5.5 VIN=5V 3.6 3.4 RIREF=120K 5 RIREF=24K 3.8 100 4.5 6 0 6.5 100 VIREF vs VIN 120 RIREF=120K 400 RIREF=24.3K 100 1 RIREF=24.3K ITRK(mA) VIREF(V) 300 ITRK vs VIN 1.4 0.8 200 IBAT (mA) VIN(V) 1.2 500 4.4 4 400 400 VBAT vs IBAT RIREF=24.3K 500 300 IBAT(mA) 0.6 0.4 80 60 40 RIREF=120K 20 0.2 0 0 4.5 5 5.5 VIN(V) HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. 6 6.5 4 4.5 5 5.5 6 VIN(V) Page 7 Sales@hypwr.com 6.5 HP4555 High Input Voltage Charger with OVP Protection and Charge Termination IPPR vs VPPR 35 35 30 30 25 25 IPPR(mA) ICHG(mA) ICHG vs VCHG 20 15 20 15 10 10 5 5 0 0 0 1 2 3 4 5 6 0 1 2 3 VCHG(V) VBAT vs Ta 4.2 OVP(V) VBAT(V) 4 3.8 3.6 3.4 3.2 3 45 65 85 105 6.9 6.8 6.7 6.6 6.5 6.4 6.3 6.2 6.1 6 OVP recovery 25 125 45 65 VIREF(V) 2.8 Vpre-th(V) 105 125 VIREF vs Ta 3 2.6 2.4 2.2 2 65 85 Ta(℃) Pre-charge Threshold vs Ta 45 6 OVP Ta(℃) 25 5 OVP vs Ta 4.4 25 4 VPPR(V) 85 Ta(℃) HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. 105 125 1.4 1.2 1 0.8 0.6 0.4 0.2 0 VIN=5V VBAT=2.5V RIREF=120K 25 35 45 55 65 75 Ta(℃) Page 8 Sales@hypwr.com 85 HP4555 High Input Voltage Charger with OVP Protection and Charge Termination IBAT vs Ta VIMIN vs Ta 0.935 120 0.93 100 IBAT(mA) VIMIN(V) 0.925 0.92 0.915 VIN=5V RIMIN=243K 0.91 80 60 VIN=5V VBAT=2.5V RIREF=120K 40 20 0.905 0.9 0 25 35 45 55 65 75 85 25 35 45 55 Ta(℃) 15 IIN(uA) ITRK(mA) 20 VIN=5V VBAT=2V RIREF=120K 0 25 35 45 55 65 75 200 180 160 140 120 100 80 60 40 20 0 85 VIN=5V VBAT=4.3V RIREF=120K 25 45 charge enabled 65 Ta(℃) 85 105 125 85 105 125 Ta(℃) ICHG vs Ta IIN vs Ta 25 180 160 140 120 100 80 60 40 20 0 20 ICHG(mA) IIN(uA) 85 IIN vs Ta 25 5 75 Ta(℃) ITRK vs Ta 10 65 charge disabled VIN=5V VBAT=4.3V RIREF=120K 15 10 VIN=5V VCHG=1V RIREF=120K 5 0 25 45 65 85 Ta(℃) HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. 105 125 25 45 65 Ta(℃) Page 9 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination IBAT vs RIREF Charge Curve 700 600 VIN=5V VBAT=3.8V VBAT=2V IBAT(mA) 500 400 500 Ich IBAT(mA) 600 Ipre-ch 300 200 400 300 200 100 100 0 0 0 50 100 150 200 250 2 300 2.5 3 4 4.5 VBAT(V) RIREF(Kohm) EOC vs RIMIN EOC vs RIMIN 12 160 140 10 RIREF=22K EOC (mA) 120 EOC (mA) 3.5 100 80 60 RIREF=120K 8 6 4 40 2 20 0 0 0 200 400 600 RIMIN (KΩ) HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. 800 1000 1200 0 2000 4000 6000 8000 10000 12000 RIMIN (KΩ) Page 10 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination OVP Test CH1:VIN VIN=0V to 10V CH3:VBAT VIN=0V to 15V VIN=0V to 20V VIN=5V to 10V VIN=5V to 15V VIN=5V to 20V HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. Page 11 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination OPERATION The HP4555 charges a Li-ion battery using a CC/CV profile. The constant current IREF is set with the external resistor RIREF (see Figure 1) and the constant voltage is fixed at 4.2V (or 4.3V, or 4.35V, or 4.4V). If the battery voltage is below a typical 2.55V trickle charge threshold, the HP4555 charges the battery with a trickle current of 20% of IREF until the battery voltage rises above the trickle charge threshold. Fast charge CC mode is maintained at the rate determined by programming IREF until the cell voltage rises to 4.2V (or 4.3V, or 4.35V, or 4.4V). When the battery voltage reaches 4.2V (or 4.3V, or 4.35V, or 4.4V), the charger enters a CV mode and regulates the battery voltage at 4.2V (or 4.3V, or 4.35V, or 4.4V) to fully charge the battery without the risk of over charge. Upon reaching an end-of-charge (EOC) current, the charger ̅̅̅̅̅̅ pin indicates the charge completion with the 𝐶𝐻𝐺 and terminate the charge current. Figure 3 shows the typical charge waveforms after the power is on. The EOC current level IMIN is programmable with the external resistor RIMIN (see Figure 1). The ̅̅̅̅̅̅ 𝐶𝐻𝐺 pin turns to low when the trickle charge starts and rises ̅̅̅̅̅̅ pin to turn to high impedance at the EOC. The 𝐶𝐻𝐺 on again when the battery voltage lower than 150mV (typically) of output voltage after the EOC is reached, and then the recharge process is beginning. voltage is higher than the POR threshold, the ̅̅̅̅̅̅ 𝑃𝑃𝑅 pin turns on the internal open-drain MOSFET to indicate a logic low signal, independent on the ̅̅̅̅ 𝐸𝑁 pin input. When the internal open-drain FET is turned off, the ̅̅̅̅̅̅ 𝑃𝑃𝑅 pin leaks less than 20µA current. When ̅̅̅̅̅̅ pin is able to sink at least 10mA turned on, the 𝑃𝑃𝑅 ̅̅̅̅̅̅ pin current under all operating conditions. The 𝑃𝑃𝑅 can be used to drive an LED (see Figure 1) or to interface with a micro- processor. Power Good Range The power good range is defined by the following three conditions: 1. VIN > VPOR 2. VIN - VBAT > VOS 3. VIN < VOVP where the VOS is the offset voltage for the input and output voltage comparator, discussed shortly, and the VOVP is the over-voltage protection threshold given in the Electrical Characteristics table. All VPOR, VOS, and VOVP have hysteresis, as given in the Electrical Characteristics table. The charger will not charge the battery if the input voltage is not in the power good range. Input and Output Comparator A thermal foldback function reduces the charge current anytime when the die temperature reaches typically 115 ℃ . This function guarantees safe operation when the printed circuit board (PCB) is not capable of dissipating the heat generated by the linear charger. The HP4555 accepts an input voltage up to 24V but disables charging when the input voltage exceeds the OVP threshold, typically 6.8V for HP4555, to protect against unqualified or faulty AC adapters. The charger will not be enabled unless the input voltage is higher than the battery voltage by an offset voltage VOS. The purpose of this comparator is to ensure that the charger is turned off when the input power is removed from the charger. Without this comparator, it is possible that the charger will fail to power down when the input is removed and the current can leak through the PFET pass element to continue biasing the POR and the Pre-Regulator blocks. PPR Indication The ̅̅̅̅̅̅ 𝑃𝑃𝑅 pin is an open-drain output to indicate the presence of the AC adapter. Whenever the input HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. Page 12 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination Dropout Voltage The constant current may not be maintained due to the RDS (ON) limit at a low input voltage. The worst case RDS(ON) is at the maximum allowable operating temperature. current, the charge current is guaranteed to have 10% accuracy with the charge current set at 100mA. When monitoring the charge current, the accuracy of the IREF pin voltage vs. the actual charge current has the same accuracy as the gain from the IREF pin current to the actual charge current. CHG Indication The ̅̅̅̅̅̅ 𝐶𝐻𝐺 is an open-drain output capable of sinking at least 10mA current when the charger starts to charge, and turns off when the EOC current is ̅̅̅̅̅̅ signal is interfaced either with a reached. The 𝐶𝐻𝐺 microprocessor GPIO or an LED for indication. EN Input ̅̅̅̅ is an active-low logic input to enable the charger. 𝐸𝑁 Drive the ̅̅̅̅ 𝐸𝑁 pin to low or leave it floating to enable the charger. This pin has a 200kΩ internal pull-down resistor so when left floating, the input is equivalent to logic low. Drive this pin to high to disable the charger. The threshold for high is given in the Electrical Characteristics table. Operation without the Battery The HP4555 relies on a battery for stability and works under LDO mode if the battery is not connected. With a battery, the charger will be stable with an output ceramic decoupling capacitor in the range of 1µF to 220µF. In LDO mode, its stability depends on load current, COUT, etc. The maximum load current is limited by the dropout voltage 4.2V, the programmed IREF and the thermal foldback. If no load, the output voltage is rippled between recharge voltage and terminated voltage, and the ̅̅̅̅̅̅ 𝐶𝐻𝐺 pin is pulled low or in high impedance periodically. The frequency of this period influenced by output capacitance. So, the output voltage is stable only with a load current more than termination current that is set by IMIN pin. Thermal Foldback IREF Pin The IREF pin has the two functions as described in the Pin Description section. When setting the fast charge HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. The thermal foldback function starts to reduce the charge current when the internal temperature reaches a typical value of 115℃. Page 13 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination APPLICATION INFORMATION Input Capacitor Selection The input capacitor is required to suppress the power supply transient response during transitions. Mainly this capacitor is selected to avoid oscillation during the start up when the input supply is passing the POR threshold and the VIN-BAT comparator offset voltage. When the battery voltage is above the POR threshold, the VIN - VBAT offset voltage dominates the hysteresis value. Typically, a 1µF X5R ceramic capacitor should be sufficient to suppress the power supply noise. Output Capacitor Selection The criterion for selecting the output capacitor is to maintain the stability of the charger as well as to bypass any transient load current. The minimum capacitance is a 1µF X5R ceramic capacitor. The actual capacitance connected to the output is dependent on the actual application requirement. HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. Layout Guidance The HP4555 uses thermally-enhanced DFN packages that have an exposed thermal pad at the bottom side of the packages. The layout should connect as much as possible to copper on the exposed pad. Typically, the component layer is more effective in dissipating heat. The thermal impedance can be further reduced by using other layers of copper connecting to the exposed pad through a thermal via array. Each thermal via is recommended to have 0.3mm diameter and 1mm distance away from other thermal vias. Input Power Sources The input power source is typically a well-regulated wall cube with 1-meter length wire or a USB port. The HP4555 can withstand up to 24V on the input without damaging the IC. If the input voltage is higher than typically 6.8V, the charger stops charging. Page 14 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination PACKAGE OUTLINE Package DFN-2x2-8L Devices per reel 4000pcs Unit mm Package Dimension： D N5 e N8 D1 k E1 E L N4 TOP VIEW b N1 BOTTOM VIEW A A1 A2 SIDE VIEW Symbol Dimensions in Millimeters Dimensions in Inches Min Max Min Max A 0.700 0.800 0.028 0.031 A1 0.000 0.050 0.000 0.002 A2 0.203 REF 0.008 REF D 1.900 2.100 0.075 0.083 D1 1.100 1.300 0.043 0.051 E 1.900 2.100 0.075 0.083 E1 0.500 0.700 0.020 0.028 b 0.180 0.300 0.007 0.012 e 0.500 TYP 0.020 TYP k 0.200 MIN 0.008 MIN L 0.250 HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. 0.450 0.010 0.018 Page 15 Sales@hypwr.com HP4555 High Input Voltage Charger with OVP Protection and Charge Termination REVISION HISTORY Version No. Date Description Preliminary 2018-09-08 - Initial preliminary release V0.1 2018-09-30 - Update typical performance characteristics V0.2 2018-10-15 - Update Order Information V0.3 2018-10-30 V0.4 2019-01-25 - Add 4.4V charge voltage V0.5 2019-06-24 - Add programmed charge current V 1.0 2019-12-02 - Update marking description HP4555 Datasheet, 2019 V1.0 Hypower Microelectronics(Shanghai)Co., Ltd. - Update description of IMIN and IREF - Update electric parameters Page 16 Sales@hypwr.com