TSM102/A DUAL OPERATIONAL AMPLIFIER - DUAL COMPARATOR AND ADJUSTABLE VOLTAGE REFERENCE .. . . OPERATIONAL AMPLIFIERS . . . LOW SUPPLY CURRENT : 200µA/amp. MEDIUM SPEED : 2.1MHz LOW LEVEL OUTPUT VOLTAGE CLOSE TO VCC- : 0.1V typ. INPUT COMMON MODE VOLTAGE RANGE INCLUDES GROUND N DIP16 (Plastic Package) COMPARATORS . .. . LOW SUPPLY CURRENT : 200µA/amp. (VCC = 5V) INPUT COMMON MODE VOLTAGE RANGE INCLUDES GROUND LOW OUTPUT SATURATION VOLTAGE : 250mV (Io = 4mA) REFERENCE ADJUSTABLE OUTPUT VOLTAGE : Vref to 32V SINK CURRENT CAPABILITY : 1 to 100mA 1% and 0.4% VOLTAGE PRECISION D SO16 (Plastic Micropackage) ORDER CODES Part number LACTH-UP IMMUNITY Package Temperature Range -40oC, +85oC TSM102I o o -40 C, +85 C TSM102AI N D • • • • PIN CONNECTIONS Output 1 Inverting Input 1 Non-inve rting Input 1 1 16 Output 4 2 15 Inve rting Input 14 Non-inverting Input 4 3 COMP V + The TSM102 is a monolithic IC that includes two op-amps, two comparators and a precision voltage reference. This device is offering space and cost saving in many applications like power supply management or data acquisition systems. February1999 V - 4 13 5 12 Non-inverting Input 3 6 11 Inve rting Input 3 Output 2 7 10 Output 3 Vref 8 9 Ca thode CC Non-inve rting Input 2 DESCRIPTION COMP Inverting Input 2 CC 1/10 TSM102 ABSOLUTE MAXIMUM RATINGS Symbol VCC Vid Vi Toper Tj Parameter Supply Voltage Differential Input Voltage Input Voltage Operating Free-air Temperature Range Maximum Junction Temperature Thermal Resistance Juction to Ambient (SO package) Value 36 36 -0.3 to +36 -40 to +125 150 150 Unit V V V o C o C o C/W ELECTRICAL CHARACTERISTICS VCC+ = 5V, VCC- = 0V, Tamb = 25oC (unless otherwise specified) Symbol ICC Parameter Total Supply Current Tmin. < Tamb < Tmax. Min Typ 0.8 Max 1.5 2 Unit mA OPERATIONAL AMPLIFIERS VCC+ = 5V, VCC = GND, R1 connected to VCC/2,Tamb = 25oC (unless otherwise specified) Symbol Vio DVio Iib Iio Avd SVR Vicm CMR Isc VOH VOL SR GBP ∅m THD Parameter Input Offset Voltage Tmin. ≤ Tamb ≤ Tmax. Input Offset Voltage Drift Input Bias Current Tmin. ≤ Tamb ≤ Tmax. Input Offset Current Tmin. ≤ Tamb ≤ Tmax. Large Signal Voltage Gain + R1 = 10k, VCC = 30V, Vo = 5V to 25V Tmin. ≤ Tamb ≤ Tmax. Supply Voltage Rejection Ratio VCC = 5V to 30V Input Common Mode Voltage Range Tmin. ≤ Tamb ≤ Tmax. Common Mode Rejection Ratio + + VCC = 30V, Vicm = 0V to (VCC ) -1.8V Output Short Circuit Current Vid = ±1V, Vo = 2.5V Source Sink High Level Output Voltage RL = 10kΩ + VCC = 30V Tmin. ≤ Tamb ≤ Tmax. Low Level Output Voltage RL = 10kΩ Tmin. ≤ Tamb ≤ Tmax. Slew Rate VCC = ±15V Vi = ±10V, RL = 10kΩ, CL = 100pF Gain Bandwidth Product R L = 10kΩ, C L = 100pF, f = 100kHz Phase Margin R L = 10kΩ,CL = 100pF Total Harmonic Distortion Min. Typ. 1 10 20 5 50 25 100 80 + (VCC ) to (VCC ) -1.8 + (VCC ) to (VCC ) -2.2 70 100 Max. 4.5 6.5 100 200 20 40 Unit mV µV/oC nA nA V/mV dB V 90 dB mA 3 3 6 6 27 26 28 V 100 150 210 mV 1.6 2 V/µs 1.4 2.1 MHz Degrees 45 % 0.05 en Cs 2/10 Equivalent Input Noise Voltage f = 1kHz 29 Channel Separation 120 nV √ Hz dB TSM102 COMPARATORS VCC+ = +5V, VCC = Ground, Tamb = 25oC (unless otherwise specified) Symbol Vio Iio Iib IOH VOL Avd Isink Vicm Vid tre trel Note 1 : Parameter Input Offset Voltage Tmin. ≤ Tamb ≤ Tmax. Input Offset Current Tmin. ≤ Tamb ≤ Tmax. Input Bias Current Tmin. ≤ Tamb ≤ Tmax. High Level Output Current Vid = 1V, VCC = Vo = 30V Tmin. ≤ Tamb ≤ Tmax. Low Level Output Voltage Vid = -1V, Isink = 4mA Tmin. ≤ Tamb ≤ Tmax. Large Signal Voltage Gain R1 = 15k, VCC = 15V, Vo = 1 to 11V Output Sink Current Vid = -1V, Vo = 1.5V Input Common Mode Voltage Range Tmin. ≤ Tamb ≤ Tmax. Differential Input Voltage Response Time - (note 1) R1 = 5.1k to VCC+, Vref = 1.4V Large Signal Response Time + Vref = 1.4V, Vi = TTL, R1 = 5.1k to VCC Min. Typ. Max. 5 9 50 150 250 400 0.1 1 Unit mV nA nA nA µA mV 250 400 700 V/mV 6 200 16 mA VCC+ -1.5 VCC+ -2 + VCC 0 0 V 1.3 V µs 300 ns The response time specified is for 100mV input step with 5mV overdrive. For larger overdrive signals, 300ns can be obtained. 3/10 TSM102 VOLTAGE REFERENCE Symbol VKA IK Parameter Cathode to Anode Voltage Cathode Current Value Vref to 36 1 to 100 Unit V mA ELECTRICAL CHARACTERISTICS Tamb = 25oC (unless otherwise specified) Symbol Parameter Min. Typ. Max. 2.475 2.490 2.500 2.500 2.525 2.510 Unit o Reference Input Voltage - (figure 1) - Tamb = 25 C TSM102, VKA = Vref, IK = 10mA TSM102A, VKA = Vref, IK = 10mA Vref V ∆Vref Reference Input Voltage Deviation Over Temperature Range - (figure 1, note1) VKA = Vref, IK = 10mA, Tmin. ≤ Tamb ≤ Tmax. ∆Vref ∆T Temperature Coefficient of Reference Input Voltage - (note 2) VKA = Vref, IK = 10mA, Tmin. ≤ Tamb ≤ Tmax. ∆Vref ∆VKA Ratio of Change in Reference Input Voltage to Change in Cathode to Anode Voltage - (figure 2) IK = 10mA, ∆VKA = 36 to 3V Iref mV 7 o ppm/ C ±22 Imin Ioff Notes : 1. ±100 mV/V -1.1 -2 µA Reference Input Current - (figure 2) IK = 10mA, R1 = 10kΩ, R 2 = ∞ o T amb = 25 C T min. ≤ Tamb ≤ Tmax. ∆Iref 30 1.5 2.5 3 µA Reference Input Current Deviation Over Temperature Range - (figure 2) IK = 10mA, R1 = 10kΩ, R 2 = ∞ T min. ≤ Tamb ≤ Tmax. 0.5 1 Minimum Cathode Current for Regulation - (figure 1) VKA = Vref 0.5 1 Off-State Cathode Current - (figure 3) 180 500 mA ∆Vref is defined as the difference between the maximum and minimum values obtained over the full temperature range. ∆Vref = Vref max. - Vref min V ref ma x. V re f min. 2. The temperature coefficient is defined as the slopes (positive and negative) of the voltage vs temperature limits whithin which the reference voltage is guaranteed. -n ma x 2.5V m in pp m / C pp m + n 25 C 3. 4/10 Te mpe rature T2 T1 ∆VKA The dynamic Impedance is defined as |ZKA| = ∆IK /C Te mp e ra ture nA TSM102 Figure 1 : Test Circuit for VKA = Vref V Input I V KA K re f Figure 2 : Test Circuit for VKA > Vref VKA Input R1 IK I re f R2 Vre f VKA = Vref (1 + R1 ) + Iref . R1 R2 Figure 3 : Test Circuit for Ioff VKA = 36V Input I o ff 5/10 TSM102 APPLICATION NOTE A Li-Ion BATTERY CHARGER USING TSM102A by R. LIOU This application note explains how to use the TSM102 in an SMPS-type battery charger which features : Voltage Control Current Control Low Battery Detection and End Of Charge Detection .. . 1 - TSM102 PRESENTATION The TSM102 integrated circuit includes two Operational Amplifiers, two Comparators and one adjustable precision Voltage Reference (2.5V to 36V, 0.4% or 1%). TSM102 can sustain up to 36V power supply voltage. Figure 1 : TSM102 Pinout 1 16 TS M102 15 2 14 3 COMP V + V 5 12 6 11 7 10 CC Vref 2 - APPLICATION CONTEXT AND PRINCIPLE OF OPERATION In the battery charging field which requires ever increasing performances in more and more reduced space, the TSM102A provides an attractive solution in terms of PCB area saving, precision and versatility. Figure 2 shows the secondary side of a battery charger (SMPS type) where TSM102A is used in optimised conditions : the two Operational Amplifiers perform current and voltage control, the two Comparators provide ”End of Charge” and ”Low Battery” signals and the Voltage Reference ensures precise reference for all measurements. The TSM102A is supplied by an auxiliary power supply (forward configuration - D7) regulated by a bipolar transistor and a zener diode on its base (Q2 and DZ), and smoothed by the capacitors C3 and 6/10 COMP CC - Ca tho de C4. R15 polarizes the base of the transistor and at the same time limits the current through the zener diode during regulation mode of the auxiliary power supply. The current and voltage regulations are made thanks to the two Operational Amplifiers. The first amplifier senses the current flow through the sense resistor Rs and compares it with a part of the reference voltage (resistor bridge R7, R8, R9). The second amplifier compares the reference voltage with a part of the charger’s output (resistor bridge R1, R2, R3). When either of these two operational amplifiers tends to lower its ouput, this linear information is propagated towards the primary side via two ORing diodes (D1, D2) and an optocoupler (D3). The compensation loops of these regulation functions are ensured by the capacitors C1 and C2. TSM102 Figure 2 : The Application Schematic - Battery Charger Secondary Side The first comparator ensures the ”Low Battery” signal generation thanks to the comparison of a part of the charger’s output voltage (resistor bridge R17, R19) and the reference voltage. Proper hysteresis is given thanks to R20. An improvement to the chargers security and to the battery’s life time optimization is achieved by lowering the current control measurement thanks to Q1 that shunts the resistor R9 when the battery’s voltage is below the ”Low Battery” level. The second comparator ensures the ”End of Charge” signal generation thanks to the comparison of a part of the charger’s output voltage (resistor bridge R1, R2, R3) and the reference voltage. When either of these two signals is active, the corresponding LED is polarized for convenient visualization of the battery status. 3 - CALCULATION OF THE ELEMENTS All the components values have been chosen for a two-Lithium-Ion batteries charge application : Current Control : 720mA (Low Battery current control : 250mA) . .. . Voltage Control : 8.4V (= 2x 4.2V) Low Battery : 5.6V (= 2x 2.5V + 0.6V) End of Charge : 8.3V (= 2x 4.15V) Current Control : The voltage reference is polarized thanks to the R4 resistor (2.5mA), and the cathode of the reference gives a fixed 2.500V voltage. I = U / R = [ Vref ( R8 + R9 ) / (R7 + R8 + R9) ] / Rs = [ 2.5 x (390 + 820) / (10000 + 390 + 820) ] / 0.375 = 720mA I = 720mA P = power dissipation through the sense resistor = R I2 = 0.375 x 0.7202 = 194mW In case of ”Low Battery” conditions, the current control is lowered thanks to the following equation : I = U / R = = [ Vref R8 / (R7 + R8) ] / Rs = [ 2.5 x 390 / (10000 + 390 ) ] / 0.375 = 250mA I (LoBatt) = 250mA Voltage Control : Vout = Vref / [ R2 / (R1 + R2 + R3) ] 7/10 TSM102 = 2.5 / [ 56 / (131.5 + 56 + 0.68 ) ] = 8.400V Vout = 8.400V The addition of the diode D9 is necessary to avoid dramatic discharge of the battery cells in case of the charger disconnection from the mains voltage, and therefore, the voltage measurement is to be operated on the cathode side of the diode not to take its voltage drop into account. The total bridge value of R1, R2, R3 must ensure low battery discharge if the charger is disconnected from main, but remains connected to the battery by mistake. The chosen values impose a 44µA discharge current max. Low Battery signal : If R5 = 0Ω and R6 = open : Vout(LoBatt) = Vref / [ R19 / ( R17 + R19 ) ] = 2.5 / [ 10 / (12.4 + 10) ] = 5.6V Vout(LoBatt) = 5.6V End of Charge signal : Vout(EOC) = Vref / [ (R2 + R3 ) / (R1 + R2 + R3) ] = 2.5 / [ (56 + 0.68) / (131.5 + 56 + 0.68) ] = 8.300V Vout (EOC)= 8.300V R12 and R13 are the equivalentresistors seen from the opamp and from the comparator. Notes: The current control values must be chosen in accordancewith the elements of the primary side. The performances of the battery charger in their globality are highly dependent on the adequation of the primary and the secondary elements. A hysteresis resistor can be connected to the ”End Of Charge” comparator to ensureproper hysteresis to this signal, but this resistor must be chosen carefully not to degrade the output voltage precision. It might be needed to impose unidirectionnal hysteresis (by inserting a diode on the positive feedback of the comparator). Figure 3 shows how to use the integrated Voltage Reference to build a precise Power Supply for the Figure 3 : A precise power supply for the TSM102A and other components Vaux Vcc Vaux + 9 + 8 13 TSM102 Vref 8/10 TSM102 PACKAGE MECHANICAL DATA 16 PINS - PLASTIC PACKAGE Dim. a1 B b b1 D E e e3 F i L Z Min. 0.51 0.77 Millimeters Typ. Max. 1.65 0.5 0.25 Min. 0.020 0.030 Inches Typ. Max. 0.065 0.020 0.010 20 8.5 2.54 17.78 0.787 0.335 0.100 0.700 7.1 5.1 3.3 0.280 0.201 0.130 1.27 0.050 9/10 TSM102 PACKAGE MECHANICAL DATA 16 PINS - PLASTIC MICROPACKAGE (SO) Dim. A a1 a2 b b1 C c1 D E e e3 F G L M S Min. Millimeters Typ. 0.1 0.35 0.19 Max. 1.75 0.2 1.6 0.46 0.25 Min. Inches Typ. 0.004 0.014 0.007 0.5 Max. 0.069 0.008 0.063 0.018 0.010 0.020 o 45 (typ.) 9.8 5.8 10 6.2 0.386 0.228 1.27 8.89 3.8 4.6 0.5 0.394 0.244 0.050 0.350 4.0 5.3 1.27 0.62 0.150 0.181 0.020 0.157 0.209 0.050 0.024 o 8 (max.) Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this pub lication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a trademark of STMicroelectroni cs 1999 STMicroelectro nics– Printed in Italy – All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - France - Germany - Italy - Japan - Korea - Malaysia - Malta - Mexico - Morocco The Netherlands - Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A. http://www.st.com 10/10