 |
|
| If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
|
|
| If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
|
| Datasheet File OCR Text: |
| TSM1012 LOW CONSUMPTION VOLTAGE AND CURRENT CONTROLLER FOR BATTERY CHARGERS AND ADAPTORS s CONSTANT VOLTAGE AND CONSTANT s s s s s s CURRENT CONTROL LOW CONSUMPTION LOW VOLTAGE OPERATION LOW EXTERNAL COMPONENT COUNT CURRENT SINK OUTPUT STAGE EASY COMPENSATION HIGH AC MAINS VOLTAGE REJECTION VOLTAGE REFERENCE s FIXED OUTPUT VOLTAGE REFERENCE s 0.5% AND 1% VOLTAGE PRECISION DESCRIPTION TSM1012 is a highly integrated solution for SMPS applications requiring CV (constant voltage) and CC (constant current) mode. TSM1012 integrates one voltage reference and two operational amplifiers (with ORed outputs common collectors). The voltage reference combined with one operational amplifier makes it an ideal voltage controller. The other operational, combined with few external resistors and the voltage reference, can be used as a current limiter. APPLICATIONS 1.25V D SO-8 (Plastic Package) S MiniSO-8 (Plastic Micropackage) PIN CONNECTIONS (top view) 1 Vref 1,25V 28V Vcc 8 2 CCCC CC+ CV Out 7 s ADAPTERS s BATTERY CHARGERS ORDER CODE Part Number TSM1012I TSM1012AI TSM1012I TSM1012AI Temperature Package Vref Range S D % -40 to 105C -40 to 105C -40 to 105C -40 to 105C * * * * 1 0.5 1 0.5 Marking 4 3 Gnd 6 CV- CV+ 5 M1012 M1012A M804 M805 D = Small Outline Package (SO) - also available in Tape & Reel (DT S = Small Outline Package (MiniSO8) - also available in Tape & Reel (ST) February 2004 1/8 TSM1012 PIN DESCRIPTION SO8 & MiniSO8 Pin out Name Vref CCCC+ CVCV+ Gnd Out Vcc Pin # 1 2 3 4 5 6 7 8 Type Analog Output Analog Input Analog Input Analog Input Analog Input Power Supply Analog Output Power Supply Function Voltage Reference Input pin of the operational amplifier Input pin of the operational amplifier Input pin of the operational amplifier Input pin of the operational amplifier Ground Line. 0V Reference For All Voltages Output of the two operational amplifier Power supply line. ABSOLUTE MAXIMUM RATINGS Symbol Vcc Vi Tstg Tj Iref ESD Rthja Rthja DC Supply Voltage DC Supply Voltage (50mA =< Icc) Input Voltage Storage temperature Junction temperature Voltage reference output current Electrostatic Discharge Thermal Resistance Junction to Ambient Mini SO8 package Thermal Resistance Junction to Ambient SO8 package Value -0.3V to Vz -0.3 to Vcc -55 to 150 150 2.5 2 180 175 Unit V V C C mA kV C/W C/W OPERATING CONDITIONS Symbol Vcc Toper DC Supply Conditions Operational temperature Parameter Value 4.5 to Vz -40 to 105 Unit V C 2/8 TSM1012 ELECTRICAL CHARACTERISTICS Tamb = 25C and Vcc = +18V (unless otherwise specified) Symbol Parameter Test Condition Min Typ Max Unit Total Current Consumption Icc Total Supply Current, excluding current in Voltage Reference1). Vcc clamp voltage Vcc = 18V, no load Tmin. < Tamb < Tmax. Icc = 50mA 100 28 180 A V Vz Operators Input Offset Voltage Vio TSM1012 TSM1012A DVio Iio Iib SVR Vicm CMR Tamb = 25C Tmin. Tamb Tmax. Tamb = 25C Tmin. Tamb Tmax. Tamb = 25C Tmin. Tamb Tmax. Tamb = 25C Tmin. Tamb Tmax. VCC = 4.5V to 28V Tamb = 25C Tmin. Tamb Tmax. 65 0 70 60 1 0.5 7 2 20 50 100 4 5 2 3 mV Input Offset Voltage Drift Input Offset Current Input Bias Current Supply Voltage Rejection Ration Input Common Mode Voltage Range Common Mode Rejection Ratio V/C 30 50 150 200 Vcc-1.5 nA nA dB V dB 85 Output stage Gm Vol Ios Transconduction Gain. Sink Current Only2) Low output voltage at 5 mA sinking current Output Short Circuit Current. Output to (Vcc-0.6V). Sink Current Only Tamb = 25C Tmin. Tamb Tmax. Tmin. Tamb Tmax. Tamb = 25C Tmin. Tamb Tmax. 6 5 0.5 1 1 250 10 400 mA/mV mV mA Voltage reference Vref Reference Input Voltage TSM1012 1% precision TSM1012A 0.5% precision Vref Tamb = 25C Tmin. Tamb Tmax. Tamb = 25C Tmin. Tamb Tmax. 1.238 1.225 1.244 1.237 1.25 1.25 20 1.262 1.273 1.256 1.261 30 20 10 V Reference Input Voltage Deviation Over Tmin. Tamb Tmax. Temperature Range Iload = 1mA Vcc = 18V, 0 < Iload < 2.5mA mV mV mV RegLine Reference input voltage deviation over Vcc range. RegLoad Reference input voltage deviation over output current. 1. Test conditions: pin 2 and 6 connected to GND, pin 4 and 5 connected to 1.25V, pin 3 connected to 200mV. 2. The current depends on the difference voltage between the negative and the positive inputs of the amplifier. If the voltage on the minus input is 1mV higher than the positive amplifier, the sinking current at the output OUT will be increased by Gm*1mA. 3/8 TSM1012 Figure 1 : Internal Schematic Vcc 1 Vref 1,25V CV+ 5 CV 8 28V Out 7 4 CV- CC+ 3 CC CC- 2 Gnd 6 Figure 2 : Typical Adapter or Battery Charger Application Using TSM1012 Rlimit optocoupler secondary side OUT+ TSM1012 C4 47nF 1 Vref 1,25V CV+ 5 R4 PWM controller C1 C2 CC+ 3 CC 4 CVCV 28V Out 7 Vcc 8 R3 Rvc1 Cvc1 22K 2,2nF C3 R2 D2 R5 optocoupler primary side D1 CC- 2 Gnd 6 Ric1 22K Cic1 2,2nF R1 Rsense Ric2 1K OUT- In the above application schematic, the TSM1012 is used on the secondary side of a flyback adapter (or battery charger) to provide an accurate control of voltage and current. The above feedback loop is made with an optocoupler. 4/8 TSM1012 PRINCIPLE OF OPERATION AND APPLICATION HINTS 1. Voltage and Current Control 1.1. Voltage Control The voltage loop is controlled via a first transconductance operational amplifier, the resistor bridge R1, R2, and the optocoupler which is directly connected to the output. The relation between the values of R1 and R2 should be chosen as written in Equation 1. R1 = R2 x Vref / (Vout - Vref) Eq1 Where Vout is the desired output voltage. To avoid the discharge of the load, the resistor bridge R1, R2 should be highly resistive. For this type of application, a total value of 100K (or more) would be appropriate for the resistors R1 and R2. As an example, with R2 = 100K, Vout = 4.10V, Vref = 1.210V, then R1 = 41.9K. Note that if the low drop diode should be inserted between the load and the voltage regulation resistor bridge to avoid current flowing from the load through the resistor bridge, this drop should be taken into account in the above calculations by replacing Vout by (Vout + Vdrop). 1.2. Current Control The current loop is controlled via the second trans-conductance operational amplifier, the sense resistor Rsense, and the optocoupler. Vsense threshold is achieved externally by a resistor bridge tied to the Vref voltage reference. Its middle point is tied to the positive input of the current control operational amplifier, and its foot is to be connected to lower potential point of the sense resistor as shown on the following figure. The resistors of this bridge are matched to provide the best precision possible The control equation verifies: Rsense x Ilim = Vsense eq2 Vsense = R5*Vref/(R4+R5) Ilim = R5*Vref/(R4+R5)*Rsense eq2' where Ilim is the desired limited current, and Vsense is the threshold voltage for the current control loop. Note that the Rsense resistor should be chosen taking into account the maximum dissipation (Plim) through it during full load operation. Plim = Vsense x Ilim. eq3 Therefore, for most adapter and battery charger applications, a quarter-watt, or half-watt resistor to make the current sensing function is sufficient. The current sinking outputs of the two trans-connuctance operational amplifiers are common (to the output of the IC). This makes an ORing function which ensures that whenever the current or the voltage reaches too high values, the optocoupler is activated. The relation between the controlled current and the controlled output voltage can be described with a square characteristic as shown in the following V/I output-power graph. Figure 3 : Output voltage versus output current Vout Voltage regulation Current regulation 0 TSM1012 Vcc : independent power supply Secondary current regulation TSM1012 Vcc : On power output Primary current regulation Iout 2. Compensation The voltage-control trans-conductance operational amplifier can be fully compensated. Both of its output and negative input are directly accessible for external compensation components. An example of a suitable compensation network is shown in Fig.2. It consists of a capacitor Cvc1=2.2nF and a resistor Rcv1=22K in series. 5/8 TSM1012 The current-control trans-conductance operational amplifier can be fully compensated. Both of its output and negative input are directly accessible for external compensation components. An example of a suitable compensation network is shown in Fig.2. It consists of a capacitor Cic1=2.2nF and a resistor Ric1=22K in series. 3. Start Up and Short Circuit Conditions Under start-up or short-circuit conditions the TSM1012 is not provided with a high enough supply voltage. This is due to the fact that the chip has its power supply line in common with the power supply line of the system. Therefore, the current limitation can only be ensured by the primary PWM module, which should be chosen accordingly. If the primary current limitation is considered not to be precise enough for the application, then a sufficient supply for the TSM1012 has to be ensured under any condition. It would then be necessary to add some circuitry to supply the chip with a separate power line. This can be achieved in numerous ways, including an additional winding on the transformer. Figure 5 : 4. Voltage clamp The following schematic shows how to realize a low-cost power supply for the TSM1012 (with no additional windings).Please pay attention to the fact that in the particular case presented here, this low-cost power supply can reach voltages as high as twice the voltage of the regulated line. Since the Absolute Maximum Rating of the TSM1012 supply voltage is 28V. In the aim to protect he TSM1012 against such how voltage values a internal zener clamp is integrated. Rlimit = (Vcc-Vz)Ivz Figure 4 : Clamp voltage cc Rlimit Ivz TSM1012 Vcc Vz 28V Rlimit optocoupler secondary side OUT+ TSM1012 C4 47nF 1 Vref 1,25V CV+ 5 R4 PWM controller C1 C2 CC+ 3 CC 4 CVCV 28V Out 7 Vcc 8 R3 Rvc1 Cvc1 22K 2,2nF C3 R2 D2 R5 optocoupler primary side D1 CC- 2 Gnd 6 Ric1 22K Cic1 2,2nF R1 Rsense Ric2 1K OUT- 6/8 TSM1012 PACKAGE MECHANICAL DATA SO-8 MECHANICAL DATA DIM. A A1 A2 B C D E e H h L k ddd 0.1 5.80 0.25 0.40 mm. MIN. 1.35 0.10 1.10 0.33 0.19 4.80 3.80 1.27 6.20 0.50 1.27 0.228 0.010 0.016 TYP MAX. 1.75 0.25 1.65 0.51 0.25 5.00 4.00 MIN. 0.053 0.04 0.043 0.013 0.007 0.189 0.150 0.050 0.244 0.020 0.050 inch TYP. MAX. 0.069 0.010 0.065 0.020 0.010 0.197 0.157 8 (max.) 0.04 0016023/C 7/8 TSM1012 PACKAGE MECHANICAL DATA 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 publication 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 registered trademark of STMicroelectronics All other names are the property of their respective owners. (c) 2004 STMicroelectronics - All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain Sweden - Switzerland - United Kingdom - United States http://www.st.com 8/8 |
Price & Availability of TSM1012I
 |
|
|
|
|
All Rights Reserved © IC-ON-LINE 2003 - 2022 |
| [Add Bookmark] [Contact Us] [Link exchange] [Privacy policy] |
|
Mirror Sites : [www.datasheet.hk]
[www.maxim4u.com] [www.ic-on-line.cn]
[www.ic-on-line.com] [www.ic-on-line.net]
[www.alldatasheet.com.cn]
[www.gdcy.com]
[www.gdcy.net] |