NJW4100V

NJW4100 Lithium-ion Battery Charger Controller IC with Timer ■GENERAL DESCRIPTION The NJW4100 is a Lithium-ion Battery Charger Controller IC with over charger timer. Charger current and voltage can individually be set by the external resistors. Therefore, it can be used for a wide range of battery cells for both 1-cell and 2-cell applications. It includes a lot of safety features for safety conscious design: Over voltage, Over discharge, temperature monitor and over charge timers. ■PACKAGE OUTLINE NJW4100M NJW4100V ■FEATURES ● Adjustable Charge Voltage ● Adjustable Pre-Charge and Full Charge Current ● Temperature Monitor ● Over Charge Timer ● Internal Re-Charge function ● Delay timers and Hysteresis inputs for high noise immunity ● Over Discharge Battery Detect ● Over Voltage Protection ● Bi-CMOS Technology ● Package Outline NJW4100M : DMP20 NJW4100V : SSOP20 ■PIN CONFIGURATION P-CHG NFB CNT GND NC F-CHG LED-G LED-R C1 C2 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 Q-CHG CS1 CS2 VS VREF V + TDET TH TL CHG-SW NJW4100M NJW4100V Ver.2005-01-20 -1- NJW4100 ■ABSOLUTE MAXIMUM RATINGS (Ta=25°C) PARAMETER SYMBOL Operating Voltage V+ C1 Pin Voltage VC1 C2 Pin Voltage VC2 TDET Pin Voltage VTDET CNT Pin Output Current ISINK-CNT LED-G Pin Output Current ISINK-G LED-R Pin Output Current ISINK-R Power Dissipation Operating Temperature Range Storage Temperature Range PD TOPR TSTG MAXIMUM RATINGS +15 +5 +5 +5 50 20 20 DMP20 :300 SSOP20 :300 -20 ~ +85 -40 ~ +125 UNIT V V V V mA mA mA mW °C °C ■ELECTRICAL CHARACTERISTICS (V+=5V, Ta=25°C) PARAMETER General Characteristics Operating Voltage Operating Current Under Voltage Lockout Block ON Threshold Voltage OFF Threshold Voltage Hysteresis Voltage Reference Voltage Block Reference Voltage Load Regulation Voltage Detection Block Quick Charge Detection Voltage Re-Charge Detection Voltage Over Voltage Detection Voltage Charge Control Block Reference Voltage VS Pin Input Bias Current Battery Connected Detection Voltage VQ-CHG VR-CHG VOV VREF-CV IVS VT-TDET VS: L→H VS: H→L VS: L→H VS Pin VS=4.2V TDET Pin VBAT VBAT VBAT x 0.71 x 0.73 x 0.75 VBAT VBAT VBAT x 0.94 x 0.95 x 0.96 VBAT VBAT VBAT x 1.015 x 1.025 x 1.035 4.17 – – 4.2 50 1.15 4.23 500 – V V V V nA V SYMBOL TEST CONDITION MIN. TYP. MAX. UNIT VOP ICC CHG-SW: OPEN – – – 2 14 3 V mA VT-ON VT-OFF VHYS 2.2 2.0 100 2.4 2.2 200 2.6 2.4 300 V V mV VREF ∆VREF IREF=0mA IREF=0mA~1mA 1.228 – 1.24 – 1.253 10 V mV Low Voltage Detection (2mA Charge) Block Charge Current ICHG1 Low Voltage Detection Voltage VLV VS=1V VS: L→H 1 2 3 VBAT VBAT VBAT x 0.455 x 0.475 x 0.495 mA V -2- Ver.2005-01-20 NJW4100 ■ELECTRICAL CHARACTERISTICS (V+=5V, Ta=25°C) PARAMETER Current Detection Block Pre-Charge /Quick Charge Block Voltage Gain Full Charge Block Voltage Gain F-CHG Pin Input Voltage Range CS1 Pin Input Bias Current CS2 Pin Input Bias Current Output Block CNT Pin Saturation Voltage CNT Pin Leak Current LED Out Block LED-G Pin Saturation Voltage LED-G Pin Leak Current LED-R Pin Saturation Voltage LED-R Pin Leak Current Timer Block OSC1 Timer Error Time OSC2 Timer Error Time CHG-SW Block ON Threshold Voltage OFF Threshold Voltage Pull-up Resistance SYMBOL TEST CONDITION MIN. TYP. MAX. UNIT AV1 AV2 VF-CHG ICS1 ICS2 CS1=3.8V, CS2=3.6V CS2=VS=4.2V, VF-CHG=96mV CS2=VS=4.2V CS1=4.2V CS2=4.2V 11.5 15.5 48 – – 12 18 – 10 10 12.5 21 – 500 500 dB dB mV nA nA VOL-CNT I SINK=20mA ILEAK-CNT V+=14V – – 0.2 – 0.5 1 V µA VOL-G ILEAK-G VOL-R ILEAK-R I SINK=10mA V+=14V I SINK=10mA V+=14V – – – – 0.2 – 0.2 – 0.5 1 0.5 1 V µA V µA ∆T1 ∆T2 C1=C2=0.01µF external Not including external deviation -10 -10 – – +10 +10 % % VSW-ON VSW-OFF RPULL-UP – 1 300 – – 500 0.25 – 700 V V kΩ Ver.2005-01-20 -3- NJW4100 ■TYPICAL APPLICATION Input VREF CS2 RP1 RP2 V + RQ1 RQ2 Q-CHG NFB P-CHG Quick Charge Control Pre-Charge Control CNT 12dB CS1 CS2 RB1 Rcs VREF R eference Voltage 1 1.24V VREF1 CVCC-ON Reference Voltage 2 4.2V VREF2 CVCC-ON VREF2 VS RB2 Full Charge Detection Quick Charge Re-Charge W hen is １-cell、 RB1：Short RB2：Open VREF GND CVCC-ON CS1 pin Quick/ Pre-Charge Charge ON/OFF 2mA Charge CLK OSC 1 PreCharge Timer Start/Stop Time Out Battery Voltage Detection F-CHG 6dB RF1 RF2 VBAT x 0.73 VBAT x 0.95 Over Voltage Detection Low Voltage Detection VBAT x 1.025 VREF C1 VBAT x 0.475 C2 OSC 2 Full Charge Timer Start/Stop Time Out Low Temperature Detection High Temperature Detection TDET TH TL LED-G LED-G Charge -ON V + LED-R Battery Connected Detection V + LED-R Control Logic RPULL-UP UVLO Lithium Ion Battery GND CHG-SW -4- Ver.2005-01-20 NJW4100 ■PIN CONFIGULATION Pin No. Pin Name 1 P-CHG 2 NFB 3 CNT 4 GND 5 NC 6 F-CHG 7 LED-G 8 LED-R 9 C1 10 C2 11 CHG-SW 12 TL 13 TH 14 TDET 15 V+ 16 VREF 17 VS 18 CS2 19 CS1 20 Q-CHG Function Pre-Charge Current Setting Current-Regulation-Loop Compensation Charge Control for Output Pin (External PNP Transistor) GND Full Charge Current Setting LED Output LED Output Pre-Charge Timer, 2mA Charge Timer, LED Blinking Cycle, Delay Time Setting Quick Timer Setting Charge ON/OFF Control Batteries Thermal (High Temperature) Setting Batteries Thermal (Low Temperature) Setting Battery Temperature Detection, Battery Connected Detection Operating Voltage Reference Voltage Output Battery Voltage Detection Charge Current Detection 2 Charge Current Detection 1 Quick Charge Current Setting ■CHARGE VOLTAGE / CURRENT for RESISTANCE SETTING Parameter Calculation formula Charge Control Voltage Low Voltage Detection Voltage Quick Charge Start Voltage Re-Charge Detection Voltage Over Voltage Detection Voltage Pre-Charge Current Quick Charge Current Full Charge Current IP-CHG = ( RB1 + RB2 x VREF-CV (4.2V) VBAT = RB2 Examples of calculation 4.2V 2.00V 3.07V 3.99V 4.305V 100mA 750mA 60mA 8.4V 3.99V 6.13V 7.98V 8.61V VBAT x 0.475 VBAT x 0.73 VBAT x 0.95 VBAT x 1.025 RP2 x VREF (1.24V) / 4) / RCS RP1 + RP2 (at. RP1:232kΩ, RP2:16kΩ, RCS=0.2Ω) RQ2 IQ-CHG = ( x VREF (1.24V) / 4) / RCS RQ1 + RQ2 (at. RQ1:128kΩ, RQ2:120kΩ, RCS=0.2Ω) RF2 IF-CHG = ( x VREF (1.24V) / 8) / RCS RF1 + RF2 (at. RF1:114.4kΩ, RF2:9.6kΩ, RCS=0.2Ω) Ver.2005-01-20 -5- NJW4100 ■TYPICAL CHARACTERISTICS Charge Control Block Reference Voltage 4.26 4.24 Reference Voltage V ( V) Reference Voltage vs. Temperature 1.25 Reference Voltage VREF (V) 1.245 1.24 (V =5V, IREF=0mA) + vs. Temperature (V+=5V, VS Pin) 4.22 4.2 REF-CV 1.235 1.23 4.18 4.16 4.14 -50 -25 0 25 50 75 o 1.225 1.22 -50 -25 0 25 50 75 100 125 o Ambient Temperature Ta ( C) 100 125 Ambient Temperature Ta ( C) Pre-Charge/Quick Charge Block Voltage Gain Pre-Charge/Quick Charge Block Voltage Gain AV1 (dB) vs. Temperature (V =5V, CS1=3.8V, CS2=3.6V) 12.6 + CHG-SW Block Threshold Voltage 0.8 Threshold Voltage (V) 0.7 0.6 0.5 0.4 0.3 0.2 -50 -25 0 25 50 75 100 125 o Ambient Temperature Ta ( C) V V SW_OFF vs. Temperature (V =5V) + 12.4 12.2 12 11.8 11.6 11.4 -50 -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) SW_ON Operating Current vs. Temperature 3 Operating Current ICC (mA) 2.5 2 1.5 1 0.5 0 -50 -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) (V+=5V, CHG-SW:OPEN) -6- Ver.2005-01-20 NJW4100 ■TYPICAL CHARACTERISTICS CNT Pin Saturation Voltage vs. Sink Current 0.5 Saturation Voltage VOL-CNT (V) 0.4 0.3 0.2 0.1 0 (V+=5V, Ta=25oC) Saturation Voltage VOL (V) 0.5 0.4 0.3 0.2 LED-R LED Pin Saturation Voltage vs. Sink Current (V+=5V, Ta=25oC) 0.1 LED-G 0 10 20 30 40 Sink Current ISINK (mA) 50 0 0 5 10 15 Sink Current ISINK (mA) 20 Oscillation Cycle vs. Capacitance Oscillation Cycle OSC1, OSC2 (ms) 100 (V+=5V, Ta=25oC) Oscillation Cycle OSC1, OSC2 (ms) 14 13 12 11 10 9 8 7 6 -50 Oscillation Cycle vs. Temperature (V+=5V, C1=C2=0.01µF) 10 1 0.001 0.01 Capacitance C1, C2 (µF) 0.1 -25 0 25 50 75 100 125 o Ambient Temperature Ta ( C) Ver.2005-01-20 -7- NJW4100 ■FEATURE DESCRIPTION 1. Voltage Detection Block (VS pin) The VS pin determines charge voltage, low voltage, over voltage, and re-charge voltage. Battery voltage conditions are constantly monitored. (Figure 1) 1-1. Charge Voltage (VS pin) Charge voltage VBAT is set using the VS pin external resistors RB1 and RB2 and the following equation: VBAT = RB1 + RB2 x VREF-CV (4.2V) RB2 To OR Circuit CVCC-ON Control Block Quick Charge Detection R echarge Detection O ver Voltage Detection Low Voltage For 1 Cell Charge Voltage Control Amp RB1 VREF2 Using the following settings makes it easy to support applications for one or two cells: for one cell, RB1= short, and RB2= open; for two cells, RB1=RB2. If you use a high resistance, the VS pin's bias current will cause incorrect values. Use as low a resistance as possible. VS RB2 VBAT x 0.73 RB1: Short RB2: Open Battery Voltage Detection VBAT x 0.95 To Charge VBAT x 1.025 Detection V x 0.475 1-2. Overcharge Detection Block (VS pin) The overcharge detection block stops charging when a Figure 1. Voltage Detection Block Configuration high voltage is detected at the VS pin. The overcharge detection voltage is obtained with the following equation: VOV=VBAT × 1.025 (typ.) When overcharge is detected, charging is prohibited and LED-R blinks. After that, charge will continue to be prohibited, even after battery voltage drops to a normal value. Turning the power off to release UVLO, battery connection detection, or CHG-SW switching will enable the charge sequence to restart. BAT 1-3. Low Voltage Detection (2mA charge) Block (VS pin, CS1 pin) The low voltage detection block detects an over-discharged battery, or an open battery caused by the battery protection circuit or the like. This will determine a 2mA charge prior to pre-charging. The low voltage detection voltage is obtained with the following equation: VLV=VBAT × 0.475 (typ.) During a 2mA charge, the block monitors battery voltage recovery while a steady 2mA current is output from the CS1 pin. (Figure 2) If voltage does not recover within a prescribed time, the timer will prohibit 2mA charging. Turning the power off to release UVLO, battery connection detection, or CHG-SW switching will enable the charge sequence to restart. 2mA Charge Current To Charge Current Control Amp 2mA Charge 12dB CS1 CS2 Rcs Low Voltage Detection Control Block VBAT x 0.475 RB1 VS RB2 To Charge Output Figure 2. 2mA Charging Block 1-4. Re-Charge Detection (VS pin) When a fully charged battery is left for a long period of time, voltage will drop due to self-discharge. The re-charge detection block detects a drop in voltage and re-charges the battery. The re-charge detection voltage is obtained with the following equation. VR-CHG=VBAT × 0.95 (typ.) -8- Ver.2005-01-20 NJW4100 ■FEATURE DESCRIPTION (CONTINUED) 2. Current Detection Block (CS1 pin, CS2 pin) A current detection resistor RCS is inserted between pin CS1 and pin CS2 to monitor battery charge current. The input voltage between pin CS1 and pin CS2 is amplified by the 12dB current detection amp and fed back to the charge current control amp. (Figure 3) 2-1. Pre-Charge Current, Quick Charge Current (P-CHG pin, Q-CHG pin) This will switch between charging with pre-charge current or quick charge current according to the level of the battery voltage VBAT that is input from the VS pin. VBAT x 0.475 to VBAT x 0.73 VBAT x 0.73 to VBAT Pre-charge control Quick charge control Pre-charge and quick charge current values are determined by the P-CHG pin and the Q-CHG pin voltage settings. Settings are made according to the following formulae. VREF Pre-Charge Current Value IP-CHG = ( RP2 x VREF (1.24V) / 4) / RCS RP1 + RP2 CS2 RP1 RP2 RQ1 RQ2 Q-CHG NFB P-CHG Pre-Charge Current Setting IQ-CHG = ( RQ2 x VREF (1.24V) / 4) / RCS RQ1 + RQ2 To OR Circuit Charge Current Control Amp Quick Charge Current Setting 12dB Quick Charge Current Value CS1 CS2 RB1 VS RB2 F-CHG Rcs 2-2. Full Charge Detection (F-CHG pin) Charge termination is determined by a set full charge current IF-CHG., which is determined by a voltage setting on the F-CHG pin. IF-CHG = ( RF2 x VREF (1.24V) / 8) / RCS RF1 + RF2 CVCC-ON To Charge Voltage Control Amp Switch Pre/Quick Charge Current Quick/ Pre-Charge Full Charge Detection Quick Charge Detection 6dB VREF RF1 RF2 To Charge Output When charging is terminated, LED-G turns on, and the sequence moves to the re-charge detection operation. VBAT x 0.73 Control Block Figure 3. Block for Controlling Pre-Charge, Quick Charge, and Block for Detecting Full Charge. Ver.2005-01-20 -9- NJW4100 ■FEATURE DESCRIPTION (CONTINUED) 3. Charge Control Output Block (CNT pin) A PNP transistor connected to the CNT pin controls the voltage and current required to charge the battery. When the CHG-SW pin and battery-connected detection are both ON the system moves to charge control mode. If battery voltage and temperature conditions are appropriate, charging will begin. During 2mA charging the PNP transistor will go to OFF status. 4. Temperature Detection Block, Battery Connected Detection Block (TDET pin, TH pin, TL pin) The charge temperature range is set with the TL pin (high temperature) and the TH pin (low temperature). The threshold voltage for the temperature detection comparator is set with the external resistors RTHL, RTH, RTL. Therefore, you can select any type of thermistor (NTC) and any charge temperature range (Figure 4). The TL pin and the TH pin are set to go to the potential states shown below for fluctuations in TDET voltage. VTL (high temperature) < VTDET (charge Temperature) < VTH (low temperature) Pin voltages are obtained from the following formulae. TDET pin (thermistor setting) RT VTDET = × VREF(1.24 V ) RTDET + RT TH pin (low temperature setting) RTH + RTL VTH = × VREF(1.24 V ) RTHL + RTH + RTL TL pin (high temperature setting) R TL VTL = × VREF(1.24 V ) R THL + R TH + R TL Charge -ON Battery Connected Detection Low Temperature Detection VREF RTDET RTHL TDET TH TL High Temperature Detection RTH RTL RT VT-TDET=1.15V To CHG-SW To UVLO Lithium Ion Battery Figure 4 Temperature Detection Block When the detected temperature goes out of the range of the set values, charging stops, and LED-R and LED-G turn off. After temperature is restored, charging recommences in line with battery voltage status. The TDET pin is also used for the battery-connected detection feature. The battery-connected detection feature determines that a battery is connected if TDET pin voltage is no greater than 1.15V(typ.), and commences charging. - 10 - Ver.2005-01-20 NJW4100 ■FEATURE DESCRIPTION (CONTINUED) 5. Delay Circuits (each detection block) Each detection block has a delay circuit and extra features for preventing malfunction due to noise or excess signals. Table 1 Delay Circuits and Extra Features. Detection Block Delay Circuit Low Voltage Malfunction Prevention Circuit CHG-SW Battery Connected Detection Delay I Temperature Detection Full Charge Detection Re-Charge Detection Low Voltage Detection Over Voltage Detection Quick Charge Detection Delay II Extra Feature Hysteresis Hysteresis Hysteresis Hysteresis – – Hysteresis Latch Hysteresis The delay circuit block receives a signal from the timer circuit to fix a delay time. For details on the relationship between the delay time and capacitors see “6. Timer Circuit Block”. 6. Timer Circuit Block (C1 pin, C2 pin) OSC1 is used for the timer that is used for pre-charge, 2mA charge and the like. OSC2 is used for the quick charge timer. You can change the time of the timers with external capacitors. Tables 2, 3 show the relationship between capacitance and time. Table 2 C1, C2 Oscillation Cycle t Capacitance (C1, C2) 4700pF 0.01µF 0.022µF 0.047µF Table 3 Timer Time Block Name Oscillation Cycle (OSC1, OSC2) t = 4.7ms t = 10ms t = 22ms t = 47ms Parameter 2mA Charge Timer Pre-Charge Timer LED R Blinking Cycle Delay I Delay II Quick Charge Timer Pre-Charge Timer Quick Charge Timer Calculation Formula 10 tx2 17 tx2 7 tx2 5 tx2 4 tx2 20 tx2 Examples 10.2s 22min. 1.28s 0.32s 0.16s 2hours 55 min. C1=0.01µF C2=0.01µF Use capacitors the have good temperature characteristics in the OSC block. Capacitor deviation will cause timer errors. Ver.2005-01-20 - 11 - NJW4100 ■FEATURE DESCRIPTION (CONTINUED) In each charge mode if time-over occurs charging is prohibited and LED-R blinks. Turning the power off to release UVLO, battery connection detection, or CHG-SW switching will enable the charge sequence to restart. NJW4100 incorporates a test mode that shortens the timer block function's test time by 1/150,000. To operate in test mode set the TH pin voltage to a value no greater than that of the TL pin. In test mode, regardless of the external timing capacitors C1, C2, the internal timer clock frequency will operate in a range of approximately 200kHz to 300kHz. The following shows calculation values when the oscillating frequency is 250kHz (4µs cycle). Table 4. Timer Times in Test Mode. Block Name Parameter 2mA Charge Timer Pre-Charge Timer LED R Blinking Cycle Delay I Delay II Quick Charge Timer Calculation Formula 10 tx2 17 tx2 7 tx2 5 tx2 4 tx2 20 tx2 Example (t = Appx. 4µs) Appx. 4ms Appx. 0.5s Appx. 0.5ms Appx. 0.13ms Appx. 64µs Appx. 4.2s Pre-Charge Timer Quick Charge Timer When the TDET pin voltage is approximately 1.2V or greater, the pre-charge / quick charge timers operate normally. If you want to further reduce the test time, setting TDET pin voltage makes it possible to run each of the timer counters divided in half. When the TDET pin is approximately 0.3V or less, the first half of the counter is bypassed. When the voltage is approximately greater than 0.4V and less than 1.1V, the second half of the counter is bypassed. Table 5. Reduced Test Time Mode Parameter Pre-Charge Timer Quick Charge Timer Calculation Formula 8 8 tx2 , tx2 9 10 tx2 , tx2 Example (t =Appx. 4µs) Appx. 1ms, Appx. 1ms Appx. 2ms, Appx. 4ms - 12 - Ver.2005-01-20 NJW4100 ■FEATURE DESCRIPTION (CONTINUED) 7. Reference Voltage Block (VREF pin) This block generates 1.24V and 4.2V reference voltages. The VREF pin outputs 1.24V. In addition to the IC internal reference voltage, this is also used as a reference voltage for charge current setting and temperature detection setting. 8. Power Block, Under Voltage Lockout Circuit (UVLO) Block (V pin, GND pin) An integrated Under Voltage Lockout circuit prevents IC malfunction when power is turned on or off. This circuit incorporates a 200mV hysteresis width to prevent chattering. + As required, insert a bypass capacitor near the IC's V pin when there is power line noise or when wires are long. 9. LED Block (LED-R pin, LED-G pin) The 2 LEDs can indicate charge status. (Figure 5) The LED drive circuit is an open collector output configuration. Therefore, it is easy to set a constant LED drive current with resistance values. The expression for setting the current that flows through the LEDs is shown below. ILED-G ≒ (Vcc - VF-LED - VOL-G) / RLED or ILED-R ≒ (Vcc - VF-LED - VOL-R) / RLED Input + ILED RLED VF-LED LED-G LED-R Figure 5. LED Drive Circuit Ver.2005-01-20 - 13 - NJW4100 ■FLOW CHART Start Check Adapter Voltage + V >2.4V YES Check B attery Connection CHG-SW Pin=GND YES Check Battery Connection VTDET