FUJITSU SEMICONDUCTOR DATA SHEET DS04-27710-2E ASSP For Power Supply Applications (Secondary battery) DC/DC Converter IC for Charging Li-ion Battery MB3888 ■ DESCRIPTION The MB3888 is a DC/DC converter IC suitable for down-conversion, using pulse-width (PWM) charging and enabling output voltage to be set to any desired level from one cell to four cells. The MB3888 provides a broad power supply voltage range and low standby current as well as high efficiency, making it ideal for use as a built-in charging device in products such as notebook PC. This product is covered by US Patent Number 6,147,477. ■ FEATURES • • • • • Output voltage setting using external resistor : 1 cell to 4 cells High efficiency : 96% (VIN = 19 V, Vo = 16.8 V) Wide range of operating supply voltages : 8 V to 25 V Output voltage setting accuracy : 5 V ± 0.74% (Ta = −10 °C to 85 °C) Charging current accuracy : ±5% (Continued) ■ PACKAGE 20-pin plastic SSOP (FPT-20P-M03) MB3888 (Continued) • Built-in frequency setting capacitor enables frequency setting using external resistor only • Oscillation frequency range : 100 kHz to 500 kHz • Built-in current detection amplifier with wide in-phase input voltage range : 0 V to VCC • In standby mode, leave output voltage setting resistor open to prevent inefficient current loss • Built-in standby current function : 0 µA (standard) • Built-in soft-start function independent of loads • Built-in totem-pole output stage supporting P-channel MOS FETs devices 2 MB3888 ■ PIN ASSIGNMENT (TOP VIEW) GND : 1 20 : CS RT : 2 19 : VCC (O) CTL : 3 18 : OUT VREF : 4 17 : VH DTC : 5 16 : VCC FB2 : 6 15 : FB1 −INE2 : 7 14 : −INE1 +INE2 : 8 13 : +INE1 OUTD : 9 12 : OUTC −INC : 10 11 : +INC (FPT-20P-M03) 3 MB3888 ■ PIN DESCRIPTION 4 Pin No. Symbol I/O Descriptions 1 GND Ground terminal. 2 RT Triangular-wave oscillation frequency setting resistor connection terminal. 3 CTL I Power supply control terminal. Setting the CTL terminal at “L” level places the IC in the standby mode. 4 VREF O Reference voltage output terminal. 5 DTC I PWM comparator block (PWM) input terminal. Compares the lowest voltage among terminals FB1, FB2, and DTC, with triangular wave and controls output. 6 FB2 O Error amplifier (Error Amp2) output terminal. 7 −INE2 I Error amplifier (Error Amp2) inverted input terminal. 8 +INE2 I Error amplifier (Error Amp2) non-inverted input terminal. 9 OUTD O With IC in standby mode, this terminal is set to “Hi-Z” to prevent loss of current through output voltage setting resistance. Set CTL terminal to “H” level and OUTD terminal to “L” level. 10 −INC I Current detection amplifier (Current Amp) input terminal. 11 +INC I Current detection amplifier (Current Amp) input terminal. 12 OUTC O Current detection amplifier (Current Amp) output terminal. 13 +INE1 I Error amplifier (Error Amp1) non-inverted input terminal. 14 −INE1 I Error amplifier (Error Amp1) inverted input terminal. 15 FB1 O Error amplifier (Error Amp1) output terminal. 16 VCC Power supply terminal for reference power supply and control circuit. 17 VH O Power supply terminal for FET drive circuit (VH = VCC − 6 V) . 18 OUT O External FET gate drive terminal. 19 VCC (O) Output circuit power supply terminal. 20 CS Soft-start capacitor connection terminal. MB3888 ■ BLOCK DIAGRAM Current Amp +INC 11 + −INC 10 − ×20 OUTC 12 Error Amp1 VREF −INE1 14 − +INE1 13 + + PWM Comp. + + + 19 VCC (O) OUT Drive − FB1 15 VH Error Amp2 VREF −INE2 7 − +INE2 8 + + VCC − 6 V 18 OUT 17 VH Bias Voltage UVLO VCC UVLO FB2 6 VREF UVLO DTC 5 OUTD 9 −2.5 V 16 VCC −1.5 V VREF 10 µA OSC CS 20 REF 45 pF bias CTL 3 CTL 5V SOFT 2 4 1 RT VREF GND 5 MB3888 ■ ABSOLUTE MAXIMUM RAGINGS Parameter Symbol Conditions VCC, VCC (O) terminal Rating Unit Min Max 28 V 60 mA Power supply voltage VCC Output current IOUT Peak output current IOUT Duty ≤ 5 % (t = 1 / fOSC × Duty) 700 mA Power dissipation PD Ta ≤ +25 °C 540* mW −55 +125 °C Storage temperature TSTG * : The package is mounted on the dual-sided epoxy board (10 cm × 10 cm) . WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current, temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings. 6 MB3888 ■ RECOMMENDED OPERATING CONDITIONS Parameter Symbol Conditions VCC, VCC (O) terminal Rating Unit Min Typ Max 8 25 V Power supply voltage VCC Reference voltage output current IREF −1 0 mA VH terminal output current IVH 0 30 mA Input voltage VINE −INE and +INE terminal 0 VCC − 1.8 V VINC −INC and +INC terminal 0 VCC V VDTC DTC terminal 0 VCC − 0.9 V OUTD terminal output voltage VOUTD 0 17 V OUTD terminal output current IOUTD 0 2 mA CTL terminal input voltage VCTL 0 25 V Output current IOUT −45 +45 mA Peak output current IOUT −600 +600 mA Oscillation frequency fOSC 100 290 500 kHz Timing resistor RT 27 43 130 kΩ Soft-start capacitor CS 0.022 1.0 µF VH terminal capacitor CVH 0.1 1.0 µF Reference voltage output capacitor CREF 0.1 1.0 µF Ta −30 +25 +85 °C Operating ambient temperature Duty ≤ 5 % (t = 1 / fosc × Duty) WARNING: The recommended operating conditions are required in order to ensure the normal operation of the semiconductor device. All of the device’s electrical characteristics are warranted when the device is operated within these ranges. Always use semiconductor devices within their recommended operating condition ranges. Operation outside these ranges may adversely affect reliability and could result in device failure. No warranty is made with respect to uses, operating conditions, or combinations not represented on the data sheet. Users considering application outside the listed conditions are advised to contact their FUJITSU representatives beforehand. 7 MB3888 ■ ELECTRICAL CHARACTERISTICS (Ta = +25 °C, VCC = 19 V, VCC (O) = 19 V, VREF = 0 mA) Symbol Pin No. Output voltage VREF 4 Input stability Line 4 Load stability Load Short-circuit output current Parameter 1. Reference voltage block [REF] 2. Under voltage lockout protection circuit block [UVLO] 3. Soft-start block [SOFT] 4. Triangular waveform oscillator block [OSC] Conditions Rating Unit Min Typ Max Ta = +25 °C 4.975 5.000 5.025 V Ta = −10 °C to +85 °C 4.963 5.000 5.037 V VCC = 8 V to 25 V 3 10 mV 4 VREF = 0 mA to −1 mA 1 10 mV Ios 4 VREF = 1 V −50 −25 −12 mA VTLH 16 VCC = VCC (O) , VCC = 6.2 6.4 6.6 V VTHL 16 VCC = VCC (O) , VCC = 5.2 5.4 5.6 V VH 16 VCC = VCC (O) 1.0* V VTLH 4 VREF = 2.6 2.8 3.0 V VTHL 4 VREF = 2.4 2.6 2.8 V Hysteresis width VH 4 0.2* V Charge current ICS 20 −14 −10 −6 µA Oscillation frequency fOSC 18 RT = 43 kΩ 260 290 320 kHz ∆f/fdt 18 Ta = −30 °C to +85 °C 1* % Threshold voltage Hysteresis width Threshold voltage Frequency temperature stability * : Standard design value. (Continued) 8 MB3888 (Ta = +25 °C, VCC = 19 V, VCC (O) = 19 V, VREF = 0 mA) Parameter Input offset voltage Symbol VIO Pin No. Conditions 7, 8, FB1 = FB2 = 2 V 13, 14 Rating Unit Min Typ Max 1 5 mV −100 −30 nA Input bias current IB 7, 8, 13, 14 Voltage gain AV 6, 15 DC 100* dB BW 6, 15 AV = 0 dB 2* MHz VFBH 6, 15 4.7 4.9 V VFBL 6, 15 20 200 mV −2 −1 mA 150 300 µA Frequency bandwidth 5-1. Error amplifier block Output voltage [Error Amp1, Error Amp2] Output source current ISOURCE 6, 15 FB1 = FB2 = 2 V 6, 15 FB1 = FB2 = 2 V Output sink current ISINK OUTD terminal output leak current ILEAK 9 OUTD = 17 V 0 1 µA OUTD terminal output ON resistor RON 9 OUTD = 1 mA 35 50 Ω Input offset current VIO 10, 11 +INC = −INC = 3 V to VCC −3 +3 mV I+INCH 11 +INC = 3 V to VCC, ∆Vin = −100 mV 20 30 µA I−INCH 10 +INC = 3 V to VCC, ∆Vin = −100 mV 0.1 0.2 µA I+INCL 11 +INC = 0 V, ∆Vin = −100 mV −180 −120 µA I−INCL 10 +INC = 0 V, ∆Vin = −100 mV −195 −130 µA VOUTC1 12 +INC = 3 V to VCC, ∆Vin = −100 mV 1.9 2.0 2.1 V VOUTC2 12 +INC = 3 V to VCC, ∆Vin = −20 mV 0.34 0.40 0.46 V VOUTC3 12 +INC = 0 V to 3 V, ∆Vin = −100 mV 1.8 2.0 2.2 V VOUTC4 12 +INC = 0 V to 3 V, ∆Vin = −20 mV 0.2 0.4 0.6 V In-phase input voltage range VCM 10, 11 0 VCC V Voltage gain AV 12 19 20 21 V/V Input current 6. Current detection amplifier block [Current Amp] Current detection voltage +INC = 3 V to VCC, ∆Vin = −100 mV * : Standard design value. (Continued) 9 MB3888 (Continued) (Ta = +25 °C, VCC = 19 V, VCC (O) = 19 V, VREF = 0 mA) Parameter Frequency bandwidth 6. Current detection amplifier block [Current Amp] Output source current 10. Bias voltage block [VH] 11. General VOUTCH 12 12 Conditions Rating Unit Min Typ Max 2* MHz 4.7 4.9 V 20 200 mV AV = 0 dB ISOURCE 12 OUTC = 2 V −2 −1 mA ISINK 12 OUTC = 2 V 150 300 µA VTL 5, 6, Duty cycle = 0 % 15 1.4 1.5 V VTH 5, 6, Duty cycle = 100 % 15 2.5 2.6 V −2.0 −0.6 µA IDTC 5 DTC = 0.4 V ISOURCE 18 OUT = 13 V, Duty ≤ 5 % (t = 1 / fOSC × Duty) −400* mA ISINK 18 OUT = 19 V, Duty ≤ 5 % (t = 1 / fOSC × Duty) 400* mA ROH 18 OUT = −45 mA 6.5 9.8 Ω ROL 18 OUT = 45 mA 5.0 7.5 Ω Rise time tr1 18 OUT = 3300 pF (equivalent to Si4435 × 1) 50* ns Fall time tf1 18 OUT = 3300 pF (equivalent to Si4435 × 1) 50* ns VON 3 IC Active mode 2 25 V VOFF 3 IC Standby mode 0 0.8 V ICTLH 3 CTL = 5 V 100 150 µA ICTLL 3 CTL = 0 V 0 1 µA Output voltage VH 17 VCC = VCC (O) = 8 V to 25 V, VH = 0 to 30 mA VCC − 6.5 VCC − 6.0 VCC − 5.5 V Standby current ICCS 16 VCC = VCC (O) , CTL = 0 V 0 10 µA Power supply current ICC 16 VCC = VCC (O) , CTL = 5 V 4 6 mA Input bias current Output ON resistor CTL input voltage Input current * : Standard design value 10 12 Threshold voltage Output sink current 9. Control block [CTL] BW VOUTCL Output source current 8. Output block [OUT] Pin No. Output voltage Output sink current 7. PWM comparator block [PWM Comp.] Symbol MB3888 ■ TYPICAL CHARACTERISTICS 10 Reference voltage vs. Power supply voltage 6 Ta = +25 °C CTL = 5 V 8 Reference voltage VREF (V) Power supply current ICC (mA) Power supply current vs. Power supply voltage 6 4 2 5 4 3 2 Ta = +25 °C CTL = 5 V VREF = 0 mA 1 0 0 0 5 10 15 20 25 0 Power supply voltage VCC (V) Reference voltage VREF (V) Reference voltage VREF (V) 3 2 1 10 15 20 25 25 30 VCC = 19 V CTL = 5 V VREF = 0 mA 5.04 5.03 5.02 5.01 5.00 4.99 4.98 4.97 4.96 4.95 −40 0 5 20 5.05 4 0 15 Reference voltage vs. Ambient temperature Ta = +25 °C VCC = 19 V CTL = 5 V 5 10 Power supply voltage VCC (V) Reference voltage vs. Load current 6 5 −20 0 20 40 60 80 100 Ambient temperature Ta ( °C) Load current IREF (mA) 1000 10 Ta = +25 °C VCC = 19 V 900 9 800 8 700 7 600 6 VREF 500 400 5 4 ICTL 300 3 200 2 100 1 0 0 5 10 15 20 Reference voltage VREF (V) CTL terminal current ICTL (µA) CTL terminal current, reference voltage vs. CTL terminal voltage 0 25 CTL terminal voltage VCTL (V) (Continued) 11 1M Ta = +25 °C VCC = 19 V CTL = 5 V 100 k 10 k 10 100 1000 Timing resistor RT (kΩ) Triangular wave oscillation frequency fOSC (kHz) Triangular wave oscillation frequency vs. Power supply voltage Triangular wave oscillation frequency vs. Timing resistor Triangular wave oscillation frequency fOSC (kHz) Triangular wave oscillation frequency fOSC (Hz) MB3888 320 315 310 305 300 295 290 285 280 275 270 265 260 Ta = +25 °C CTL = 5 V RT = 43 kΩ 0 5 10 15 20 25 30 Power supply voltage VCC (V) Triangular wave oscillation frequency vs. Ambient temperature 320 315 310 305 300 295 290 285 280 275 270 265 260 −40 VCC = 19 V CTL = 5 V RT = 43 kΩ −20 0 20 40 60 80 100 Ambient temperature Ta ( °C) (Continued) 12 MB3888 (Continued) Error amplifier gain and phase vs. Frequency Ta = +25 °C 40 AV VCC = 19 V 4.2 V 180 240 kΩ φ 20 90 0 0 −90 −20 Phase φ (deg) Gain AV (dB) 10 kΩ 10 kΩ 1 µF + 14 2.4 kΩ IN (7) − + + 20 13 (8) 10 kΩ 10 kΩ 15 (6) OUT Error Amp1 (Error Amp2) 2.5 V −180 −40 1k 10 k 100 k 1M 10 M Frequency f (Hz) Current detection amplifier and phase vs. Frequency Ta = +25 °C 40 180 20 90 φ 0 0 −20 −90 Phase φ (deg) Gain AV (dB) AV VCC = 19 V 10 kΩ 1 µF + 11 + 10 − IN 12 10 kΩ OUT Current Amp 16.8 V −40 −180 1k 10 k 100 k 1M 10 M Frequency f (Hz) Power dissipation PD (mW) Power dissipation vs. Ambient temperature 600 540 500 400 300 200 100 0 −40 −20 0 20 40 60 80 100 Ambient temperature Ta ( °C) 13 MB3888 ■ FUNCTIONAL DESCRIPTION 1. DC/DC Converter Unit (1) Reference voltage block (REF) The reference voltage generator uses the voltage supplied from the VCC terminal (pin 16) to generate a temperature-compensated, stable voltage (5.0 V Typ) used as the reference supply voltage for the IC’s internal circuitry. This terminal can also be used to obtain a load current to a maximum of 1 mA from the reference voltage VREF terminal (pin 4) . (2) Triangular wave oscillator block (OSC) The triangular wave oscillator builds the capacitor for frequency setting into, and generates the triangular wave oscillation waveform by connecting the frequency setting resistor with the RT terminal (pin 2) . The triangular wave is input to the PWM comparator on the IC. (3) Error amplifier block (Error Amp1) This amplifier detects the output signal from the current detection amplifier (Current amp1) , compares this to the +INE1 terminal (pin 13) , and outputs a PWM control signal to be used in controlling the charging current. In addition, an arbitrary loop gain can be set up by connecting a feedback resistor and capacitor between the FB1 terminal (pin 15) and −INE1 terminal (pin 14) , providing stable phase compensation to the system. Connecting a soft-start capacitor to the CS terminal (pin 20) prevents rush currents when the IC is turned on. Using an error amplifier for soft-start detection makes the soft-start time constant, independent of the output load. (4) Error amplifier block (Error Amp2) This amplifier (Error Amp2) detects the output voltage from the DC/DC converter and outputs the PWM control signal. External output voltage setting resistors can be connected to the error amplifier inverse input terminal to set the desired level of output voltage from 1 cell to 4 cells. In addition, an arbitrary loop gain can be set by connecting a feedback resistor and capacitor from the FB2 terminal (pin 6) to the −INE2 terminal (pin 7) of the error amplifier, enabling stable phase compensation to the system. Connecting a soft-start capacitor to the CS terminal (pin 20) prevents rush currents when the IC is turned on. Using an error amplifier for soft-start detection makes the soft-start time constant, independent of the output load. (5) Current detector amplifier block (Current Amp) The current detection amplifier (Current Amp) detects a voltage drop which occurs between both ends of the output sense resistor (RS) due to the flow of the charge current, using the +INC terminal (pin 11) and −INC terminal (pin 10) . Then it outputs the signal amplified by 20 times to the error amplifier (Error Amp1) at the next stage. (6) PWM comparator block (PWM Comp.) The PWM comparator circuit is a voltage-pulse width converter for controlling the output duty of the error amplifiers (Error Amp1 and Error Amp2) and DTC terminal (pin 5) depending on their output voltage. 14 MB3888 The PWM comparator circuit compares the triangular wave generated by the triangular wave oscillator to the error amplifier output voltage or DTC terminal voltage, and turns on the external output transistor during the interval in which the triangular wave voltage is lower than the error amplifier output voltage. (7) Output block (OUT) The output circuit uses a totem-pole configuration capable of driving an external P-channel MOS FET. The output “L” level sets the output amplitude to 6 V (Typ) using the voltage generated by the bias voltage block (VH) . This results in increasing conversion efficiency and suppressing the withstand voltage of the connected external transistor in a wide range of input voltages. (8) Control block (CTL) Setting the CTL terminal (pin 3) at “L” level places the IC in the standby mode. (The supply current is 10 µA at maximum in the standby mode.) Setting the CTL terminal at “H” level generates an internal reference voltage, placing the system under outputting status. CTL function table CTL Power OUTD L OFF (Standby) Hi-Z H ON (Active) L (9) Bias voltage block (VH) The bias voltage circuit outputs VCC −6 V (Typ) as the minimum potential of the output circuit. In the standby mode, this circuit outputs the potential equal to VCC. 2. Protection Functions Under voltage lockout protection circuit (UVLO) The transient state or a momentary decrease in supply voltage or internal reference voltage (VREF) , which occurs when the power supply (VCC) is turned on, may cause malfunctions in the control IC, resulting in breakdown or degradation of the system. To prevent such malfunction, the under voltage lockout protection circuit detects a supply voltage or internal reference voltage drop and fixes the OUT terminal (pin 18) to the “H” level. The system restores voltage supply when the supply voltage or internal reference voltage reaches the threshold voltage of the under voltage lockout protection circuit. Protection function (UVLO) operation table When UVLO is operating (VCC or VREF voltage is lower than UVLO threshold voltage) . OUTD OUT CS Hi-Z H L 3. Soft-Start Function Soft-start block (SOFT) Connecting a capacitor to the CS terminal (pin 20) prevents surge currents when the IC is turned on. Using an error amplifier for soft-start detection makes the soft-start time constant, being independent of the output load of the DC/DC converter. 15 MB3888 ■ SETTING THE CHARGING VOLTAGE The charging voltage (DC/DC output voltage) can be set by connecting external voltage setting resistors (R3, R4) to the −INE2 terminal (pin 7) according to the voltage at the +INE2 terminal (pin 8) . Be sure to select a resistor value that allows you to ignore the on resistor (35 Ω, 1 mA) of the internal FET connected to the OUTD terminal (pin 9) .In standby mode, the charging voltage is applied to OUTD termial. Therefore, output voltage must be adjusted so that voltage applied to OUTD terminal is 17 V or less. Battery charging voltage : VO VO (V) = (R3 + R4) / R4 × +INE2 (V) VO <Error Amp2> R3 −INE2 7 R4 − + + 9 OUTD 20 CS +INE2 8 ■ METHOD OF SETTING THE CHARGING CURRENT The charge current (output limit current) value can be set with the voltage at the +INE1 terminal (pin 13) . If a current exceeding the set value attempts to flow, the charge voltage drops according to the set current value. Battery charge current setting voltage : +INE1 +INE1 (V) = 20 × I1 (A) × RS (Ω) ■ METHOD OF SETTING THE TRIANGULAR WAVE OSCILLATION FREQUENCY The triangular wave oscillation frequency can be set by the timing resistor (RT) connected the RT terminal (pin 2) . Triangular wave oscillation frequency : fOSC fOSC (kHz) =: 12690 / RT (kΩ) 16 MB3888 ■ METHOD OF SETTING THE SOFT-START TIME (1) Setting constant voltage mode soft-start For preventing rush current upon activation of IC, the IC allows soft-start using the capacitor (CS) connected to the CS terminal (pin 20) . When CTL terminal (pin 3) is placed under “H” level and IC is activated (VCC ≥ UVLO threshold voltage) , Q2 is turned off and the external soft-start capacitor (CS) connected to the CS terminal is charged at 10 µA. Error Amp output (FB2 terminal (pin 6) ) is determined by comparison between the lower voltage of the two non-inverted input terminals (+INE2 terminal (pin 8) and CS terminal voltage) and inverted input terminal voltage (−INE2 terminal (pin 7) voltage) . Within the soft-start period (CS terminal voltage < +INE2) , FB2 is determined by comparison between −INE2 terminal voltage and CS terminal voltage, and DC/DC converter output voltage goes up proportionately with the increase of CS terminal voltage caused by charging on the soft-start capacitor. Soft-start time is obtained from the following formula : Soft-start time : ts (time to output 100 %) tS (s) =: 0.42 × CS (µF) , at +INE2 = 4.2 V = 4.9 V CS terminal voltage = 4.2 V (+INE2) Comparison with Error Amp block −INE2 voltage. =0V Soft-start time : ts VREF 10 µA 10 µA FB2 6 − + + −INE2 7 CS +INE2 CS 20 Error Amp2 8 Q2 UVLO 4.2 V Soft-start circuit 17 MB3888 (2) Setting constant current mode soft-start For preventing rush current upon activation of IC, the IC allows soft-start using the capacitor (CS) connected to the CS terminal (pin 20) . When CTL terminal (pin 3) is placed under “H” level and IC is activated (VCC ≥ UVLO threshold voltage) , Q2 is turned off and the external soft-start capacitor (CS) connected to the CS terminal is charged at 10 µA. Error Amp output (FB1 terminal (pin 15) ) is determined by comparison between the lower voltage of the two non-inverted input terminals (+INE1 terminal (pin 13) and CS terminal voltage) and inverted input terminal voltage (−INE1 terminal (pin 14) voltage) . Within the soft-start period (CS terminal voltage < +INE1) , FB1 is determined by comparison between −INE1 terminal voltage and CS terminal voltage, and DC/DC converter output voltage goes up proportionately with the increase of CS terminal voltage caused by charging on the soft-start capacitor. Soft-start time is obtained from the following formula : Soft-start time : ts (time to output 100 %) tS (s) =: +INE2 / 10 (µA) × CS (µF) CS terminal voltage = 4.9 V Comparison with Error Amp block −INE1 voltage. = +INE2 =0V Soft-start time : tS VREF 10 µA 10 µA FB1 15 − + + −INE1 14 CS +INE1 CS 20 13 Q2 Soft-start circuit 18 Error Amp1 UVLO MB3888 ■ PROCESSING WITHOUT USING OF THE CS TERMINAL When soft-start function is not used, the CS terminal (pin 20) should be left open. “Open” CS 20 When no soft-start time is specified ■ PROCESSING WITHOUT USING OF THE DTC TERMINAL When external duty control is not performed using DTC terminal, make a short circuit between the DTC terminal (pin 5) and VREF terminal (pin 4) with a shortest-possible wire. 4 VREF 5 DTC When DTC terminal is not used 19 MB3888 ■ NOTE ON AN EXTERNAL REVERSE-CURRENT PREVENTIVE DIODE • Insert a reverse-current preventive diode at one of the three locations marked * to prevent reverse current from the battery. • When selecting the reverse current prevention diode, be sure to consider the reverse voltage (VR) and reverse current (IR) of the diode. 19 VCC (O) VIN * 11 18 10 OUT * I1 RS * VH 17 20 Battery BATT SW1 R15 120 Ω Q2 R16 200 kΩ SW2 Q3 R21 1.5 kΩ R6 51 kΩ R5 10 kΩ R12 30 kΩ R14 1 kΩ R19 100 kΩ CS 0.022 µF R17 100 kΩ R18 200 kΩ R13 20 kΩ R23 200 kΩ R22 12 kΩ 10 11 CS OUTD DTC FB2 20 9 5 6 8 7 15 13 C6 1500 pF R3 330 kΩ +INE2 −INE2 FB1 C10 5600 pF R9 10 kΩ +INE1 OUTC 12 R8 100 kΩ −INE1 14 −INC +INC ×20 VREF VREF + + − SOFT 10 µA Error Amp2 VREF + + − Error Amp1 − + Current Amp 45 pF RT 43 kΩ OSC 2 RT − C9 0.1 µF bias VREF 4 5V GND 1 CTL VREF UVLO VCC UVLO Bias Voltage VH OUT 18 VCC (O) 19 3 CTL VCC 16 VH 17 VCC − 6 V Drive OUT REF −1.5 V −2.5 V UVLO PWM Comp. + + + C5 0.1 µF C7 0.1 µF L1 + C3 100 µF + RS 0.033 Ω I1 IIN Battery VO AC Adaptor Note: Set output voltage so that voltage applied to OUTD terminal is 17 V or less. Output voltage (Battery voltage) is adjustable. C2 100 µF D1 22 µH Q1 C11 C12 10 µF 10 µF VIN = 13.6 V to 25 V (at 3 cell) VIN = 17.8 V to 25 V (at 4 cell) MB3888 ■ APPLICATION EXAMPLE 21 MB3888 ■ PARTS LIST COMPONENT ITEM SPECIFICATION Q1 Q2 P-ch FET N-ch FET D1 Diode L1 Inductor 22 µH C2, C3 CS C5 C6 C7 C9 C10 C11, C12 Electrolytic condenser Ceramics Condenser Ceramics Condenser Ceramics Condenser Ceramics Condenser Ceramics Condenser Ceramics Condenser Ceramics Condenser RS RT R3 R5 R6 R8 R9 R12 R13 R14 R15 R16, R18, R23 R17, R19 R21 R22 Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor PARTS No. VDS = −30 V, ID = ±8 A (Max) VISHAY SILICONIX VDS = 60 V, ID = 0.115 A (Max) VISHAY SILICONIX Si4435DY 2N7002E VF = 0.42 V (Max) , at IF = 3 A ROHM RB053L-30 3.5 A, 31.6 mΩ TDK SLF12565T220M3R5 100 µF 0.022 µF 0.1 µF 1500 pF 0.1 µF 0.1 µF 5600 pF 10 µF 25 V (10 %) 50 V 50 V 10 V 50 V 50 V 10 V 25 V SANYO TDK TDK MURATA TDK TDK MURATA TDK 25CV100AX C1608JB1H223K C1608JB1H104K GRM39B152K10 C1608JB1H104K C1608JB1H104K GRM39B562K10 C3225JF1E106Z 0.033 Ω 43 kΩ 330 kΩ 10 kΩ 51 kΩ 100 kΩ 10 kΩ 30 kΩ 20 kΩ 1 kΩ 120 Ω 200 kΩ 100 kΩ 1.5 kΩ 12 kΩ 1.0 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % 0.5 % SEIDEN TECHNO ssm ssm ssm ssm ssm ssm ssm ssm ssm ssm ssm ssm ssm ssm SRS1R033F RR0816P433D RR0816P334D RR0816P103D RR0816P513D RR0816P104D RR0816P103D RR0816P303D RR0816P203D RR0816P102D RR0816P121D RR0816P204D RR0816P104D RR0816P152D RR0816P123D Note : VISHAY SILICONIX : VISHAY Intertechnology, Inc. ROHM : ROHM CO., LTD. TDK : TDK Corporation SANYO : SANYO Electric Co., Ltd. SEIDEN TECHNO : SEIDEN TECHNO CO., LTD. MURATA : Murata Manufacturing Co., Ltd. ssm : SUSUMU Co., Ltd. 22 VENDOR MB3888 ■ REFERENCE DATA Conversion efficiency vs. Charge current (Constant current mode) Conversion efficiency vs. Charge current (Constant voltage mode) 98 96 94 92 90 100 Ta = +25 °C VIN = 19 V BATT charge voltage = set at 12.6 V SW1 = SW2 = ON Efficiency η (%) = (VBATT × IBATT) / (VIN × IIN) × 100 Conversion efficiency η (%) Conversion efficiency η (%) 100 88 86 84 82 80 10 m Ta = +25 °C 98 VIN = 19 V 96 BATT charge voltage = set at 12.6 V SW1 = SW2 = ON 94 Efficiency η (%) = 92 (VBATT × IBATT) / (VIN × IIN) × 100 90 88 86 84 82 80 100 m 1 10 0 2 BATT charge current IBATT (A) 8 10 12 14 16 Conversion efficiency vs. Charge current (Constant current mode) 100 98 96 94 92 Ta = +25 °C VIN = 19 V BATT charge voltage = set at 16.8 V SW1 = SW2 = ON Efficiency η (%) = (VBATT × IBATT) / (VIN × IIN) × 100 90 88 86 84 82 100 m 1 BATT charge current IBATT (A) 10 Conversion efficiency η (%) 100 Conversion efficiency η (%) 6 BATT charge voltage VBATT (V) Conversion efficiency vs. Charge current (Constant voltage mode) 80 10 m 4 98 96 94 92 Ta = +25 °C VIN = 19 V BATT charge voltage = set at 16.8 V SW1 = SW2 = ON Efficiency η (%) = (VBATT × IBATT) / (VIN × IIN) × 100 90 88 86 84 82 80 0 2 4 6 8 10 12 14 16 18 20 BATT charge voltage VBATT (V) (Continued) 23 MB3888 BATT voltage vs. BATT charge current (set at 12.6 V) BATT voltage vs. BATT charge current (set at 16.8 V) 20 18 Ta = +25 °C, VIN = 19 V BATT : Electronic load, (Product of KIKUSUI PLZ-150W) 14 12 Dead Battery MODE (SW1 = OFF, SW2 = ON) 10 8 Resume MODE (SW1 = ON, SW2 = OFF) Suspend MODE (SW1 = ON, SW2 = ON) 6 4 2 0 16 14 0.5 1 1.5 2 2.5 3 3.5 4 BATT charge current IBATT (A) 4.5 5 Dead Battery MODE (SW1 = OFF, SW2 = ON) 12 10 Resume MODE (SW1 = ON, SW2 = OFF) Suspend MODE (SW1 = ON, SW2 = ON) 8 6 4 2 0 0 Ta = +25 °C, VIN = 19 V BATT : Electronic load, (Product of KIKUSUI PLZ-150W) 18 BATT voltage VBATT (V) BATT voltage VBATT (V) 16 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 BATT charge current IBATT (A) (Continued) 24 MB3888 Switching waveform constant voltage mode (set at 12.6 V) VBATT (mV) Ta = +25 °C VIN = 19 V 100 BATT = 1.5 A 98 mVp-p VBATT 0 Switching waveform constant current mode (set at 12.6 V, with 10 V) VBATT (mV) Ta = +25 °C VIN = 19 V 100 BATT = 3.0 A 118 mVp-p VBATT 0 −100 VD (V) 15 −100 VD (V) 15 VD 10 10 5 5 0 0 0 1 2 3 4 5 6 7 8 9 10 (µs) Switching waveform constant voltage mode (set at 16.8 V) VBATT (mV) Ta = +25 °C 100 VIN = 19 V BATT = 1.5 A 0 VBATT 46 mVp-p 0 4 5 = +25 °C VBATT (mV) Ta VIN = 19 V 100 BATT = 3.0 A 10 5 5 0 0 3 3 6 7 8 9 10 (µs) Switching waveform constant current mode (set at 16.8 V, with 10 V) 10 2 2 94 mVp-p VBATT 4 5 6 7 8 VD −100 VD (V) 15 VD 1 1 0 −100 VD (V) 15 0 VD 9 10 (µs) 0 1 2 3 4 5 6 7 8 9 10 (µs) (Continued) 25 MB3888 Soft-start operating waveform constant voltage mode (set at 12.6 V) VBATT (V) 20 Ta = +25 °C VIN = 19 V BATT = 12 Ω 10 0 VCS (V) 4 Discharge operating waveform constant voltage mode (set at 12.6 V) VBATT (V) 20 VBATT 10 ts = 9.6 ms VCS 2 IIN (A) 2 0 1 VBATT 0 VCS (V) 4 IIN (A) 2 2 VCS IIN IIN 0 1 0 0 VCTL (V) 5 VCTL (V) 5 VCTL Ta = +25 °C VIN = 19 V BATT = 12 Ω VCTL 0 0 0 2 4 6 8 0 10 12 14 16 18 20 (ms) Soft-start operating waveform constant current mode (set at 12.6 V) VBATT (V) 20 6 8 10 12 14 16 18 20 (ms) VBATT (V) 20 10 VBATT 0 VCS (V) 4 4 Discharge operating waveform constant current mode (set at 12.6 V) VBATT Ta = +25 °C VIN = 19 V BATT = 4 Ω 10 2 ts = 9.8 ms 0 VCS 2 IIN (A) 2 0 1 VCS (V) 4 IIN (A) 2 2 IIN VCS 0 1 IIN 0 VCTL (V) 5 VCTL 0 0 VCTL (V) 5 Ta = +25 °C VIN = 19 V BATT = 4 Ω VCTL 0 0 2 4 6 8 10 12 14 16 18 20 (ms) 0 2 4 6 8 10 12 14 16 18 20 (ms) (Continued) 26 MB3888 (Continued) Soft-start operating waveform constant voltage mode (set at 16.8 V) VBATT (V) 20 VBATT (V) 20 Ta = +25 °C VIN = 19 V BATT = 12 Ω 10 Discharge operating waveform constant voltage mode (set at 16.8 V) VBATT 10 VBATT 0 VCS (V) 4 ts = 9.6 ms 0 VCS 2 IIN (A) 2 0 1 IIN VCS (V) 4 IIN (A) 2 2 VCS 0 1 IIN 0 VCTL (V) 5 0 VCTL (V) 5 VCTL 0 Ta = +25 °C VIN = 19 V BATT = 12 Ω VCTL 0 0 2 4 6 8 10 12 14 16 18 20 (ms) 0 Soft-start operating waveform constant current mode (set at 16.8 V) VBATT (V) 20 4 6 8 10 12 14 16 18 20 (ms) Discharge operating waveform constant current mode (set at 16.8 V) VBATT (V) 20 Ta = +25 °C VIN = 19 V BATT = 4 Ω 10 2 10 VBATT 0 VCS (V) 4 ts = 9.6 ms VBATT 0 VCS VCS (V) 4 2 IIN (A) 2 2 0 1 0 IIN (A) 2 IIN IIN VCS 0 0 VCTL (V) 5 VCTL 1 VCTL (V) 5 Ta = +25 °C VIN = 19 V BATT = 4 Ω VCTL 0 0 0 2 4 6 8 10 12 14 16 18 20 (ms) 0 2 4 6 8 10 12 14 16 18 20 (ms) 27 MB3888 ■ USAGE PRECAUTIONS • Printed circuit board ground lines should be set up with consideration for common impedance. • Take appropriate static electricity measures. • Containers for semiconductor materials should have anti-static protection or be made of conductive material. • After mounting, printed circuit boards should be stored and shipped in conductive bags or containers. • Work platforms, tools, and instruments should be properly grounded. • Working personnel should be grounded with resistance of 250 kΩ to 1 MΩ between body and ground. • Do not apply negative voltages. • The use of negative voltages below −0.3 V may create parasitic transistors on LSI lines, which can cause malfunction. ■ ORDERING INFORMATION Part number MB3888PFV 28 Package 20-pin plastic SSOP (FPT-20P-M03) Remarks MB3888 ■ PACKAGE DIMENSION 20-pin plastic SSOP (FPT-20P-M03) Note 1) * : These dimensions do not include resin protrusion. Note 2) Pins width and pins thickness include plating thickness. * 6.50±0.10(.256±.004) 0.17±0.03 (.007±.001) 11 20 * 4.40±0.10 6.40±0.20 (.173±.004) (.252±.008) INDEX Details of "A" part +0.20 1.25 –0.10 +.008 .049 –.004 LEAD No. 1 10 0.65(.026) "A" 0.24±0.08 (.009±.003) 0.10(.004) C (Mounting height) 0.13(.005) M 0~8° 0.50±0.20 (.020±.008) 0.45/0.75 (.018/.030) 0.10±0.10 (Stand off) (.004±.004) 0.25(.010) 1999 FUJITSU LIMITED F20012S-3C-5 Dimensions in mm (inches) 29 MB3888 FUJITSU LIMITED All Rights Reserved. The contents of this document are subject to change without notice. Customers are advised to consult with FUJITSU sales representatives before ordering. The information and circuit diagrams in this document are presented as examples of semiconductor device applications, and are not intended to be incorporated in devices for actual use. Also, FUJITSU is unable to assume responsibility for infringement of any patent rights or other rights of third parties arising from the use of this information or circuit diagrams. The products described in this document are designed, developed and manufactured as contemplated for general use, including without limitation, ordinary industrial use, general office use, personal use, and household use, but are not designed, developed and manufactured as contemplated (1) for use accompanying fatal risks or dangers that, unless extremely high safety is secured, could have a serious effect to the public, and could lead directly to death, personal injury, severe physical damage or other loss (i.e., nuclear reaction control in nuclear facility, aircraft flight control, air traffic control, mass transport control, medical life support system, missile launch control in weapon system), or (2) for use requiring extremely high reliability (i.e., submersible repeater and artificial satellite). Please note that Fujitsu will not be liable against you and/or any third party for any claims or damages arising in connection with above-mentioned uses of the products. Any semiconductor devices have an inherent chance of failure. You must protect against injury, damage or loss from such failures by incorporating safety design measures into your facility and equipment such as redundancy, fire protection, and prevention of over-current levels and other abnormal operating conditions. If any products described in this document represent goods or technologies subject to certain restrictions on export under the Foreign Exchange and Foreign Trade Law of Japan, the prior authorization by Japanese government will be required for export of those products from Japan. F0209 FUJITSU LIMITED Printed in Japan