AIC1783A Battery Charge Controller for Low Power Charging FEATURES DESCRIPTION z Fast Charge Control of NiMH/NiCd Batteries. The AIC1783A fast charge controller IC is z Fast Charge Termination by: −ΔV , 0 ΔV Safety Timer, Maximum Voltage. designed for intelligent charging of NiMH or NiCd batteries without the risk of overcharge. −ΔV z Protection against Battery Voltage Fault. detection (-0.25%) and 0 ΔV detection (peak z Pulsed Trickle Charge Mode. voltage z Quick and Easy Testing for Production. employed by the AIC1783A to terminate fast z 8-pin DIP or SO Packages. charge. The fast charge can also be cut off by timer) are the primary methods maximum battery voltage along with the safety APPLICATIONS timer to prevent charging under fault conditions of the charging system or the battery itself. Battery Fast Chargers for: z Mobile Phones. z Notebook and Laptop Personal Computers. z Portable Power Tools and Toys. z Portable Communication Equipment. z Portable Video & Stereo Equipment. The safety timer period is adjustable for flexible usage that AIC1783A could be applied in the wide range of battery capacity. Test mode is provided for charger manufactures to dramatically reduce production test time. TYPICAL APPLICATION CIRCUIT VIN=5V R3 10K D3 LL4148 R7 100K 2SC4672 R2 0.5 Q1 R1 680 + C1 47μF D1 D2 LL4148 LL4148 2 Cells NiMH/NiCd R4 68K R6 100K C2 C3 R5 220K 4.7μF 0.1μF R8 120K LED1 U1 1 REF VCC 8 2 TIMER VBT 7 R9 3 MODE ICON 6 200K 4 GND LED 5 R10 680 AIC1783A *Note: ICHARGE=380mA @VBAT=2.8V Linear Charger for 2 Cells NiMH/NiCd Batteries Analog Integrations Corporation Si-Soft Research Center DS-1783AG-01 20100119 3A1, No.1, Li-Hsin Rd. I , Science Park , Hsinchu 300, Taiwan , R.O.C. TEL: 886-3-5772500 FAX: 886-3-5772510 www.analog.com.tw 1 AIC1783A ORDERING INFORMATION A IC178 3A XX XX P IN CO NFIG URA TIO N TO P V IE W P ACK ING TYP E TR: TA PE & REE L TB: TUBE REF 1 8 VC C 2 7 VBT M OD E 3 6 ICON 4 5 LED T IM ER P ACK AG E TYP E N: P LA STIC DIP S : SM AL L O UTLINE GN D C: C OM ME RCIA L P : LE AD FR EE CO MM ERCIA L G :G REE N P ACK AG E E xa mple: A IC17 83CS TR Æ in SO P -8 Pa ckag e & Ta pe & Re el Packing Typ e (CN is not available in TR p acking t yp e) A IC17 83P STR Æ in SO P -8 Lea d Free P ackage & Tap e & Ree l Pa ckin g Type AIC1 783 GS TR Æ in SO P -8 G re en P acka ge & Tap e & Reel Pa cking Typ e ABSOLUTE MAXIMUM RATINGS Supply Voltage ....................................…….......…………........................................ 5.5V DC Voltage Applied on any pin ......................……………...................................... 5.5V Sink current of ICON pin, LED pin ............……………….........……….................. 20mA Operating Temperature Range .............................................………...... -40°C~ 85°C Storage Temperature Range .............................................…………...... -65°C~ 150°C TEST CIRCUIT 5V 1 REF 100K VCC 2 TIMER VBT MODE ICON 3 RTIMER 100K 120K 4 GND LED 8 5V + 7 6 5 680 - VOLTAGE SOURCE 680 AIC1783A RED GREEN 5V 2 AIC1783A ELECTRICAL CHARACTERISTICS (T =25°C, V CC=5V, A PARAMETER TEST CONDITIONS unless otherwise specified.) SYMBOL MIN. TYP. MAX. UNIT Supply Voltage VCC 4.5 5.0 5.5 V Supply Current ICC Battery Low During Initial Timer Voltage Protection Limit After Initial Timer VBT Battery High 1.1 mA 0.11 0.16 0.21 0.63 0.69 0.75 2.6 2.7 2.80 25 50 V LED, ICON Pins Output Impedance ON OFF 1 MODE pin Input Impedance VBT pin Recommended External Resistor of TIMER pin −ΔV Detection accuracy 300 VBT=2V KΩ 1 RTIMER Ω MΩ MΩ 2 100 1000 KΩ -0.15 -0.25 -0.35 % 3 AIC1783A TYPICAL PERFORMANCE CHARACTERISTICS (TA=25°C, RTIMER=100KΩ, VCC=5V, refer to Test Circuit) 81.5 81.0 Safety Timer (min) Supply Current (mA) 1.08 1.02 0.96 0.90 80.5 80.0 79.5 79.0 78.5 0.84 4.4 4.6 4.8 5.0 5.2 78.0 4.4 5.4 4.6 4.8 VCC (V) 5.4 5.6 1.05 Supply Current (mA) 4.4 Frequency (Hz) 5.2 Fig. 2 Safety Timer vs. Supply Voltage Fig. 1 Supply Current vs. Supply Voltage 4.2 4.0 3.8 3.6 4.4 4.6 4.8 5.0 5.2 5.4 1.00 0.95 0.90 0.85 0.80 0 5.6 20 40 60 80 Temperature (°C) VCC (V) Fig. 3 LED Flashing Frequency vs. Supply Voltage Fig. 4 Supply Current vs. Temperature 82 5.0 81 4.8 Frequency (Hz) Safety Timer (min) 5.0 VCC (V) 80 79 78 77 76 4.6 4.4 4.2 4.0 3.8 3.6 75 0 20 40 60 Temperature (°C) Fig. 5 Safety Timer vs. Temperature 80 3.4 -20 0 20 40 Temperature (°C) 60 80 Fig. 6 LED Flashing Frequency vs. Temperature 4 AIC1783A TYPICAL PERFORMANCE CHARACTERISTICS (Continued) 2.80 0.84 2.76 VBT (V) VBT (V) 0.80 2.72 2.68 0.76 0.72 0.68 2.64 0.64 2.60 0 20 40 60 0 80 40 60 80 Temperature (°C) Fig. 8 VBT (Low) Limit vs. Temperature (After Initial Timer) Temperature (°C) Fig. 7 VBT (High) Limit vs. Temperature 33 Output Impedance (O) 0.20 0.18 VBT (V) 20 0.16 0.14 0.12 0 Fig. 9 20 40 60 80 Temperature (°C) VBT (Low) Limit vs. Temperature (During Initial Timer) 30 27 24 21 0 20 40 60 80 Temperature (°C) Fig.10 Output Impedance vs. Temperature (LED, ICON Pins) 5 AIC1783A BLOCK DIAGRAM MODE MODE Selection GND VCC TIMER Bandgap Reference & Voltage Regulator Oscillator LED Display Control Unit Charge Control REF Battery Voltage Protection Setting ICON State Machine 13-bit A/D Charge Control Unit Battery Voltage Protection VBT PIN DESCRIPTIONS PIN 1: REF- Reference voltage input, PIN 5: LED- acceptable voltage range : indicate the battery charging (VCC-1.4V) ~ (0.5VCC+0.4V) status. PIN 2: TIMER- Determining of PIN 6: ICON- Open-drained output, used to safety timer with an external control the charging current to resistor connected to GND. the battery. PIN 3: MODE- Determining the the period mode of PIN 7: VBT- operation for the AIC1783A. PIN 4: GND- Open-drained output used to Power ground. Divided battery voltage input to sense the battery voltage. PIN 8: VCC- Power supply input at 5V±10%. 6 AIC1783A APPLICATION INFORMATIONS z Maximum battery voltage OPERATION Power-On and Battery Pre-Qualifying When power is first applied to the AIC1783A, all -ΔV Cutoff internal digital circuit blocks of the AIC1783A are The AIC1783A makes a voltage sampling at VBT reset by the internal power-on-reset circuitry and pin every 4 seconds when safety timer period is set output LED flash 3 times to indicate the initiation of equal to 80 minutes. If a negative delta voltage of power-on. The internal control unit then examines 0.25% compared to its peak value is detected at the battery condition through the VBT pin. VBT pin, the fast charge cycle is terminated. The acceptable range of VBT pin is 0.16V to 2.7V. If 0ΔV Cutoff the voltage of VBT pin fails to fall within the If the battery voltage stays at its peak value or predetermined acceptable limits, the AIC1783A decreases very slowly for the duration determined enters a charge-suspending mode, in which all the by the peak voltage timer which is 6% of safety internal circuitry remains in reset state. timer, the fast charge action is terminated. Fast Charge Maximum Safety Timer Cutoff After the battery passes fault checks, fast charging The maximum fast charge period is determined by begins while initial timer and safety timer of the AIC1783A start counting. Functions of −ΔV the safety timer, which is set by a resistor detection, peak voltage timer, and maximum battery connected from TIMER pin to GND. Safety timer, −ΔV , sampling rate will be longer if the resistor voltage are, however, disabled temporarily until the value is larger. When the value of the resistor is initial timer period in the initial stage of a charge 100KΩ, the safety timer period equals 80 minutes. cycle elapses. The initial timer period is equal to After the safety timer period is finished, the fast 1/80 of safety timer. charge action is terminated. Maximum Voltage Cutoff Since the low limit of acceptable VBT voltage is only The AIC1783A guards against the maximum limits about 0.16V during the initial timer period, even for battery voltage during fast charging. If either of deeply discharged batteries can easily qualify to be these limits is exceeded, fast charge action is fast charged subsequently. terminated. In the course of fast charge, the AIC1783A constantly monitors the voltages at VBT pin. The fast charge process is switched to trickle charge when any one of the following situations is encountered, which are explained below: z Negative delta voltage ( −ΔV ) z Peak voltage timer ( 0 ΔV ) Trickle Charge The trickle charge after the fast charge to prevent the loss of charge due to battery self-discharging. The duty cycle is set to 1/128 by internal circuitry. z Maximum charge time 7 AIC1783A The functions and charging states control mentioned above are illustrated in the function flow Setting the Period of Safety Timer The AIC1783A provides a method for linearly chart of AIC1783A (Fig. 12) adjusting the period of safety timer with an external resistor connected from TIMER pin to GND. The relation between safety timer length and the external resistor (RTIMER) is shown in Fig. 13. The DESIGN GUIDE table following shows the resistor values for some Battery Voltage Measurement of the commonly chosen safety timer periods. Also The AIC1783A measures the battery voltage shown in the table are their corresponding oscillator through VBT pin, which is connected to battery frequencies. positive terminal through a resistor-divider network, as shown in Fig. 11. 800 VBAT RTIMER (KΩ) 600 RA R5 VBT C6 0.1μF 100K + C5 4.7μF RB 7 400 200 AIC1783A 0 0 100 200 300 400 500 Safety Timer (min.) Fig. 13 Safety Timer vs. RTIMER Fig. 11 Battery Voltage Divider The suggested divider resistance of RA and RB for the corresponding number of battery cells are as below: TABLE 1 BATTERY CELLS RA/RB RA (KΩ) RB (KΩ) 2~4 2 240 120 3~6 3.3 300 91 4~8 4.9 300 62 5~10 6.4 300 47 6~12 7.8 310 39 8~16 10.8 390 36 8 AIC1783A Power ON LED Flash 3 Times If VBT in Normal Range No LED Displays Abnormal, ICON ON, Safety Timer Reset Yes Charging (ICON OFF) No If Initial Timer Finished Yes If VBT in Normal Range No Yes If 0ΔV is Detected LED Display Fast Charge (ICON OFF) Yes Yes No If -0.25% ΔV is Detected Yes LED Display Battery Fulll, Fast Charge Finished, Trickle Charge Starts Battery Replacement No No No If Safety Timer Period has Finished Fig. 12 Yes Function Flow Chart of AIC1783A 9 AIC1783A TABLE 2 Display the Battery Charging Status OSC. Safety timer Freq.(KHz) (min.) 11 256 10 23 131 20 48 65.8 40 74 43.1 60 100 32.8 80 152 21.6 120 206 16.0 160 314 10.6 250 491 6.89 380 667 5.04 520 RTMR (KΩ) The AIC1783A provides an open-drained output, LED pin, to indicate the battery charging status. The outputs of LED pin are shown in the following table: Power ON LED 1Hz Fast Charge Fault Charging Completed Conditions 4Hz ON Flashing OFF Charging Current Control As shown in the typical application circuit, the Selecting Mode of Operation AIC1783A offers an open-drained output pin, ICON The AIC1783A provides three modes of operation: pin, to control the charging current flow in fast normal, test, and AC mode determined by the charge state and switch on to inhibit the charging setting of MODE pin. The AIC1783A will operate current flow in fault conditions. When fast charge is normally when the MODE pin is left floating (a completed, the AIC1783A enters the trickle charge 0.1μF capacitor is recommended to be tied to mode. In trickle charge mode, the ICON pin output MODE pin if the charge circuit works in a noisy switches with 1/128 duty cycle. environment). When the MODE pin is biased to GND, the function of -ΔV detection is disabled. Power Fast Charge Fault When the MODE pin is biased to VCC, the AIC1783A enters the test mode. The test mode can ON Charging Completed Conditions ON OFF 1/128 be used to significantly reduce production test time. ICON ON Duty cycle TABLE 3 MODE pin Mode VCC Test Function Safety timer period scaled down to 1/32 Floating Normal GND AC Normal operation -ΔV detection disabled 10 AIC1783A APPLICATION EXAMPLE U1 VIN 11~15V C5 1μF 1N4148 D3 + 78L05 VIN VOUT GND + C6 10μF R3 100K R1 U2 1 REF L1 + R10 D1 SS24 120/0.25W D4 U3 R9 1 390K 2 3 C7 470P 4 8 DC BOOST DE IS CF VCC 6 GND FB 7 5 AIC1563 IN4148 R2 D2 C2 220μF C3 0.1μF BAT1 **BATTERY 1μF RED SS24 220μH C1 LED1 R4 120K 1K 240K R11 100K R5 120K C4 0.1μF + C9 4.7μF C10 R12 47nF 150K VCC 2 TIMER VBT 3 MODE ICON 4 GND LED 8 R6 R7 7 680 47K R8 10K 6 Q1 5 MMBT2222A AIC1783A RS 0.5/0.25W + C8 220μF **: 2~4 NiMH/NiCd cells Note: Charge Current: 0.3V/Rs Ampere Safety Timer: 120 min Fig. 14 Switching Battery Charger Circuit with Wide Input Voltage Range 11 AIC1783A PHYSICAL DIMENSIONS (unit: mm) SOP-8 D h X 45° A A SOP-8 MILLIMETERS MIN. MAX. A 1.35 1.75 A1 0.10 0.25 B 0.33 0.51 C 0.19 0.25 D 4.80 5.00 E 3.80 e SEE VIEW B 4.00 1.27 BSC H 5.80 6.20 h 0.25 0.50 L 0.40 1.27 θ 0° 8° A e H E S Y M B O L WITH PLATING 0.25 C A1 B GAUGE PLANE SEATING PLANE L VIEW B BASE METAL SECTION A-A θ z Note: 1. Refer to JEDEC MS-012AA. 2. Dimension "D" does not include mold flash, protrusions or gate burrs. Mold flash, protrusion or gate burrs shall not exceed 6 mil per side . 3. Dimension "E" does not include inter-lead flash or protrusions. 4. Controlling dimension is millimeter, converted inch dimensions are not necessarily exact. 12 AIC1783A z DIP-8 E D 0.38 E1 GAUGE PLANE eA S Y M B O L b A1 A b2 A e c L A1 WITH PLATING D1 BASE METAL SECTION A-A Note: 1. Refer to JEDEC MS-001BA 2. Dimension "D" does not include mold flash, protrusions or gate burrs. Mold flash, protrusion or gate burrs shall not exceed 10 mil per side . 3. Dimension "D1"and "E1" do not include inter-lead flash or protrusions. 4. Controlling dimension is millimeter, converted inch dimensions are not necessarily exact. DIP-8 MILLIMETERS MAX. MIN. A A A2 eB 5.33 0.38 A2 2.92 4.95 b 0.36 0.56 b2 1.14 1.78 c 0.20 0.35 D 9.01 10.16 D1 0.13 E 7.62 8.26 E1 6.10 7.11 e 2.54 BSC eA 7.62 BSC eB L 10.92 2.92 3.81 Note: Information provided by AIC is believed to be accurate and reliable. However, we cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AIC product; nor for any infringement of patents or other rights of third parties that may result from its use. We reserve the right to change the circuitry and specifications without notice. Life Support Policy: AIC does not authorize any AIC product for use in life support devices and/or systems. Life support devices or systems are devices or systems which, (I) are intended for surgical implant into the body or (ii) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 13