Mitsubishi Integrated Circuit <Digital/Analog Interface> M62256FP Single chip battery charger control IC Outline M62256FP is a semiconductor integrated circuit designed to control the battery charger. This IC controls not only all the time sequence needed for battery charging,but also gives full support for detection of battery temperature,protection over current and voltage,and safety timer,etc. It is also a simple matter to charge Ni-Cd,Ni-MH batteries by adding a small peripheral components to this IC. This IC has a feedback controlling of the charge current and the output voltage. Pin Configuration(Top view) Features • Designed for low voltage(3V)operation. • Built-in CR oscillator is used for internal logic. • Built-in initialization timer and safety timer enable -∆V error detection and over-charging. • Built-in D/A converter and shift-resister circuits to maintain the peak voltage of battery. • Built-in Main output SW and discharge drive circuits. • Built-in LED drive circuits for displaying the status of the power supply and charging/discharging. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 M62256FP C1 E1 C2 E2 C3 E3 Rc Cc Dchg IN Dchg OUT Chg SW GND2 Batt SW Dchg SW Adpt SW Test1 Test2 N.C • Built-in System Reset circuit for detecting the power supply voltage. Vref1 I SET2 I SET1 OCSET PCS OUT PCS IN CP1 I DET Vcc GND1 CP2 VDET P.C Batt T Vref2 Batt Batt + N.C 36P2R • Built-in temperature detection circuit for the Ni-MH battery • Built-in voltage and current control circuit which enables feedback to the primary side of the SMPS. Uses • Built-in protective functions including detection of over-voltage in charge mode and over-current in adapter mode, and others. General electronic battery charger for VCR and camera in one unit, handheld telephones, etc. Block diagram Vcc Vref2 Vref1 Iset2 22 28 36 35 Iset1 34 Stabl'd Pwr. Sup. System to internal Reset ckt. circuit to internal circuit P.C 24 VDET 25 CP2 26 Detect unplugged PS cord + – + – CP1 30 PSC IN PSC OUT 31 C1 C2 C3 E1E2 E3 Chg SW 1 5 3 2 4 6 LED driver Dchg OUT 11 10 Output SW driver Discharge driver Dchg IN I DET 9 Discharge current control Control logic Voltage control OP Amp. Voltage set-up ckt. Current set-up ckt. Over-current det. ckt. Safety timer Current control OP Amp. -∆V error det. prev. logic 32 Oscillator 12 7 8 GND2 (A.GND) Rc Cc Clock gen. ckt. Test ckt. 16 17 Battery temp det. ckt. Batt. voltage det. ckt. -∆V det. logic 33 Test1 Test2 OCSET 27 GND (P.GND) 29 14 Dchg SW 13 Batt SW 15 Adpt SW 23 Batt T 20 Batt + 21 Batt – Mitsubishi Integrated Circuit <Digital/Analog Interface> M62256FP Single chip battery charger control IC Functions of Terminal Explained Terminal No. Symbols Functions 1, 3, 5 C1,C2,C3 LED drive terminals (Open collector outputs) 2, 4, 6 E1,E2,E3 7, 8 Rc, Cc 9 Dchg IN These terminals are used to set the LED drive currents. These terminals are used to set the oscillating frequency of the internal clocks. This is an input terminal used to detect the current which is used for the discharge current feedback. 10 Dchg OUT This is the drive terminal for the transistor mounted externally for discharge purposes. 11 Chg SW This is the SW drive terminal used for charging battery. GND1, 2 These are grounding terminals. (GND1 is for logic and GND2 is for analog.) 13 Batt SW This is used to detect mounting of battery.(It is pulled up internally) 14 Dchg SW This is used to detect the discharge SW.(It is pulled up internally) 15 Adpt SW This is used to detect adapter SW.(It is pulled up internally) 27, 12 16 , 17 20 Test1, 2 These are Test Mode set-up terminal.(It is pulled up internally) Batt + This terminal is connected to the + terminal of the battery. 21 Batt – This terminal is connected to the - terminal of the battery. 23 Batt T This terminal is connected to the temperature detecting terminal of the battery. 22 Vref2 This is the voltage reference terminal for temperature detection. 24 P.C V DET This terminal is connected to the photo-coupler used for feedback. 25 26, 30 This terminal is used to make connection with capacitor(s) and resistor(s) CP1, CP2 which are used for phase compensation. 29 I DET 31 PCS IN 32 33 34, 35 36 This terminal is used to monitor the output voltage. This terminal is used to detect the charging current or output current. This is an input terminal used for photo-coupler short. PCS OUT This terminal goes "H" when over-current is detected. OC SET This terminal is used to set the over-current detection value when the adapter mode is used. Iset1, 2 These are used to set the charging current.(Iset1 is for quick charge and Iset2 is for the trickle charge.) Vref1 This terminal is sets the standard voltage for over-current set-up value and the charge current set-up. Mitsubishi Integrated Circuit <Digital/Analog Interface> M62256FP Single chip battery charger control IC Absolute Maximum Ratings (Ta=25˚C unless specified otherwise) Items Symbols Condition Ratings Unit Power supply voltage Vcc 16 V Chgon terminal drive current IChgon 50 mA Dchgout terminal drive current IDchg -5 mA LED drive current I C1~C3 20 mA P.C drive current IP.C 5 mA Vref1 output current Iref1 -1 mA Vref2 output current Iref2 -1 mA Power dissipation Pd 650 mW Thermal derating ratio K Ta=25˚C 6.5 mW/˚C Operating temperature Topr Ta>25˚C -20~+75 ˚C Storage temperature Tstg -40~+125 ˚C (Notes) Polarity of current: The direction of current flowing into the IC is considered positive(+). The direction of current flowing out of the IC is considered negative(-). The voltage impressed on the open collector output terminal should be the absolute maximum voltage of the power supply. The voltage difference between the negative terminal of the battery and the GND terminal should be 0V~0.6V. Mitsubishi Integrated Circuit <Digital/Analog Interface> M62256FP Single chip battery charger control IC Electrical Characteristics (Vcc=7V, Ta=25˚C unless specified otherwise) All device Items Power supply voltage Circuit current Power supply detecting voltage Symbols Vcc Icc VTHVcc Conditions Vcc=7V when quick charge Standard Min 3.0 18.0 2.66 Typ 27.0 2.80 Max 15.0 40.0 2.94 Unit V mA V Reference Items Vref1 output voltage Vref2 output voltage Items OCSET terminal flow out current ISET1 terminal flow out current 1 ISET1 terminal flow out current 2 ISET2 terminal flow out current 1 ISET2 terminal flow out current 2 Symbols Vref1 Vref2 Symbols IOCSET ISET1-1 ISET1-2 ISET2-1 I SET2-2 Standard Conditions Iref1=150uA Iref2=350uA Conditions OCSET=220mV Excluding charging time When charging Excluding trickle charging time When trickle charging Min 1.18 1.70 Typ 1.25 1.80 Max Unit 1.32 V V 1.90 Standard Min -1 30 -1 30 -1 Typ 50 50 Max Unit uA 85 uA uA uA 85 uA Driver Items Chgon terminal output L voltage Dchgout terminal H voltage LED output L voltage DchgIN terminal detecting voltage Symbols VsatChg VOH Dchg Vsat LED V DchgIN Conditions I Chgon =50mA I Dchgout =5mA,Vcc=7V I LED =5mA Standard Min – – – 0.5 Typ 0.3 5.2 0.3 0.8 Max Unit 0.6 V 6.0 V V 0.6 V 1.2 Control Section Items Range of input voltage Input bias current P.C output L voltage PCS OUT terminal flow out current PCS IN terminal threshold voltage Symbols Conditions V IN I Bias V PCL I PCSOUT V THPCSIN When over-current is detected Symbols Conditions IPC =2mA Standard Min 0 -1 Typ – 0.2 -10 0.8 -18 0.5 Max Vcc 0.5 -5 1.2 Unit V uA V uA V Each SW Detection Terminal Items Batt SW terminal flow out current Batt SW terminal threshold voltage Dchg SW terminal flow out current Dchg SW terminal threshold voltage Adpt SW terminal flow out current Adpt SW terminal threshold voltage I BattSW VTHBatt I DchgSW VTHDchg I AdptSW VTHAdpt Vcc=7V, V BattSW =0V Vcc=7V Vcc=7V, V DchgSW =0V Vcc=7V Vcc=7V, V AdptSW =0V Vcc=7V Standard Min -240 3.0 -240 3.0 -240 3.0 Typ -140 5.6 -140 5.6 -140 5.6 Max Unit uA -80 6.0 V uA -80 V 6.0 uA -80 V 6.0 Mitsubishi Integrated Circuit <Digital/Analog Interface> M62256FP Single chip battery charger control IC Internal Voltage Set-up Items Set-up output voltage at Adpt mode Set-up output voltage at charge mode Set-up output voltage when over-current is detected ISET1 set-up voltage ISET2 set-up voltage OCSET set-up voltage Over-voltage set-up voltage -∆V detection voltage1 -∆V detection voltage2 Voltage at the end of discharge Temperature detection set-up voltage1 Temperature detection set-up voltage2 Over-heating detection set-up voltage Items Symbols Conditions VAdpt VCHG V DOWN V ISET1 When quick charging V ISET2 When trickle charging VOCSET When adapter mode VOVP V -∆V-1 within Initialization timer after initialization timer has passed V -∆V-2 VCHGON VTTH1 Temperature at the start of charging Temperature at the start of recharging V TTH2 Charge stop temperature VO/H Symbols Conditions Standard Min 820 1.19 Typ 864 1.26 478 504 123 11.4 208 9.0 0.6 60 4.7 0.92 1.06 0.81 130 12.0 220 9.5 1.0 100 5.0 0.97 1.12 0.86 Standard Max 910 1.33 Unit mV V 530 mV 137 12.6 232 10 1.4 140 5.3 1.02 1.18 0.91 mV mV mV V V mV V V V V Unit Min Typ Max Oscillation frequency fosc 9.22 10.24 11.26 KHz Rc=30KÉ∂ , Cc=2200pF Initialization timer1 Tm1 Battery voltage<5V 18.0 20.0 22.0 min 5V≤Battery voltage<6.5V 4.5 5.0 5.5 min Initialization timer2 Tm2 Initialization timer3 Battery voltage≥6.5V Tm3 2.7 3.0 3.3 min Undetected time for -É¢V T NDET 2.7 3.0 3.3 min hr Safety timer1 Tms1 when quick charging 2.7 3.0 3.3 Safety timer2 Tms2 when trickle charging 21.6 24 26.4 hr Over-current detection time TOC 9.0 10.0 11.0 sec Note: The time given to each timer is when the oscillation frequency of 10.24KHz is used. Recommended Operating Range Power supply voltage (Vcc) …………………… 3~15V Charge current (See Note1) Preliminary charge ……………………… 50~200mA Quick charge …………………………… 0.8~2A Trickle charge …………………………… 80~200mA Discharge current (See Note1) ………………… 300~500mA LED drive current (See Note2) ………………… 115mA Note1. The charging current must be set according to the battery specifications. The currents used for quick charge and trickle charge are detemined by the voltage of the terminals Iset1 and Iset2 and current sense resistor R4 (Application in page 9). Note2. The LED drive current is calculated by the following equation. 200mV I LED •=• (A) RL Mitsubishi Integrated Circuit <Digital/Analog Interface> M62256FP Single chip battery charger control IC FUNCTION DESCRIPTION 1. Charging Operation (1) Detection of Battery When the Batt SW terminal shows "L", it indicates that the battery is installed (2) Conditions for Quick Charge As soon as the battery is installed, its voltage and temperature are detected. If the battey voltage is below 5V, the preliminary charging mode starts. When the battery voltage exceeds 5V, the quick charge commences. On the other hand, if the battery voltage exceeds 5V, the following will take place. If the battery temperature is less than 55˚C, the quick charge will take place. If it is higher than 55˚C, the preliminary charge mode will continue until the temperture falls below 55˚C. The charge current used for the quick charge is set by Iset1. (3) Initialization timer The initialization timer is set according to Table1. The -∆V is not detected fot 3 minutes. Detection of -∆V within the initialization timer is set to 1V to prevent erroneous detection of -∆V during the initial charging. Table1 Setting up the initialization timer The initial battery voltage Less than 5V More than 5V but less than 6.5V 6.5V or more Time of initializaton timer 20min. 5min. 3min. (4) Charge control When the initialization timer completes its function, detection of -∆V is set to 100mV and the peak voltage of the battery held inside is compared against the battery voltage detected. After -∆V is detected, the trickle charge starts at the current set by Iset2. (5) Safety Timer The Safety Timer controls the charging time. The quick charging time stops 3 hours and the trickle charging time ends after 24 hours. (6) Protective functions (a) Over-voltage detection ………… Charging stops when the battery voltage goes to 9.5V or higher. (b) Over-heat detection ………… Charging stops when the battery temperature becomes 63˚C or higher. When the temperature goes to 45˚C or lower, It recharges once. (c) Power supply voltage detection When the power supply voltage goes below 2.8V, the initial eset takes place. (d) Unplugged power supply cord … When the unplugged power supply cord is detected, the output SW is turned off. (7) Appliciable batteries Ni-Cd battery, Ni-MH(nickel-metalhydrogen) battery (∆T/∆t, V taper can not be detected.) Mitsubishi Integrated Circuit <Digital/Analog Interface> M62256FP Single chip battery charger control IC 2. Adapter Mode Operation (1) Adapter Mode The adapter mode (Adapter standby mode) goes into effect when both the battery and the adapter are not connected. The fixed voltage mode (7.2V) is set. (2) Detection of Adapter Adpt SW is used for detection of Adapter. When this terminal goes "H", Adapter is judged to be present. If Adapter is connected during charging, charging is discontinued and the Adapter Mode goes into effect. (The Adapter Mode has priority.) (3) Setting Up the Output Voltage The output voltage at the time of the Adapter Mode is set the internally set 7.2V. (4) Protection Function The over-current protection function is the only one protective function active during the Adapter Mode. The current value is set by the voltage at the OCSET terminal. When the over-current is detected, the output is controlled as shown in the following flow chart, The RESET will take place when Adpt SW terminal goes "L". Over-current detection No 10 sec. has passed? Yes Output down (4.2V set) No 10 sec. has passed? Yes PCS OUT terminal "H" Mitsubishi Integrated Circuit <Digital/Analog Interface> M62256FP Single chip battery charger control IC 3. Discharge Operation (1) Discharge Control The Dchg SW terminal is used for the forced discharge of the battery. Discharge starts when this terminal stays "L" 0.7seconds or more. The Dchg IN terminal and the Dchg OUT terminal are used to control discharge. These terminal contain the feedback function which enables constant current discharge. (2) Detection of Adapter When the voltage of the battery which has been discharging reaches 5V or less, the discharge Mode has canceled. ( Charging Mode takes over.) (3) Forced Ending of Discharge Once the discharge mode is in progress, it is possible to cancel the discharge mode by making the Dchg SW terminal to "L" once more. (Stays 0.7 seconds or more.) (4) RESET Operation The RESET circuit goes into operation when the power supply voltage goes 2.8V(typ) or lower. The internal logic circuit are all RESET to the initial states. (5) Modes Setting The Adapter Mode has the highest priority. Modes are switched in the following. (a) When the power is turned ON Power ON puts the Adapter Mode in Standby Batt IN causes the Charge Mode to take over. Adpt IN causes the Adapter Mode to take over. (b) When the battery is connected … * Quick charge ………………… Adpt IN causes the Adapter Mode to take over. Adpt IN causes the initial RESET to start and the Adapter Mode goes into operation. Adpt OUT starts the Charging Mode by way of the initial check. * Trickle charge ………………… Adpt IN sets the Charge OFF and the Adapter Mode takes over. The Charge OFF Mode continues after Adpter OUT. * Charge OFF …………………… Adpt IN causes temporary stop. Then, the Adapter Mode takes over. * Charge standby (Preliminary charge) ……… Continues after Adpt OUT (c) When the battery is disconnected during the Adapter is in operation Adpt IN Batt OUT Adpt OUT Adapter Mode standby Adpt IN Batt OUT Batt IN Adpt OUT : It is assumed that a different battery connected and the Charge Mode starts by way of the initial check. 31 PCS IN Vcc + C2 28 L1 32 RL3 RL2 RL1 LED3 7 Rc 6 E3 4 E2 2 E1 8 30K Cc 2200P Rc Cc R1 33 R12 4.4K R11 20.6K 36 V DET 25 RP2 CP2 CP2 26 11.32K R13 34 35 R15 120 16 N.C ISET2 Test1 R14 1.06K ISET1 CP1 30 29 9 T – 23 21 20 Batt SW 13 Vref2 22 Batt Batt Batt + Dchg SW 14 Dchg IN Dchg OUT 10 17 N.C 27 12 Q2 R9 SW3 SW2 3K 1K 9K R8 D3 D2 R5 SW1 R6 R10 Q1 I DET Chg SW 11 R4 0.1Ω Adpt SW 15 Test2 GND1 GND2 0.1µ 0.1µ RP1 CP1 R3 1.2K M62256FP P.C 24 P.C L2 R2 8.8K Vref1 OCSET 5 C3( Discharge LED) PCS LED1 OUT 1 C1( Power Supply LED) LED2 3 C2( Charge LED) D1 C1 Application example M62256FP R7 Åú T - + To Batt To Adapter Mitsubishi Integrated Circuit <Digital/Analog Interface> M62256FP Single chip battery charger control IC