Datasheet

ManualsBrandsSTMICROELECTRONICS ManualsLinear ICsLinear IC - Op-amp Current sensor SO 8

April 2011 Doc ID 16875 Rev 2 1/26

TSC1031

High-voltage, high-side current sense amplifier

Features

■ Independent supply and input common-mode

voltages

■ Wide common-mode operating range:

2.9 to 70 V in single-supply configuration

-2.1 to 65 V in dual-supply configuration

■ Wide common-mode surviving range:

-16 to 75 V (reversed battery and load-dump

conditions)

■ Supply voltage range:

2.7 to 5.5 V in single supply configuration

■ Low current consumption: I

max = 360 µA

■ Pin selectable gain: 50 V/V or 100 V/V

■ Buffered output

■ EMI filtering

Applications

■ Automotive current monitoring

■ DC motor control

■ Photovoltaic systems

■ Battery chargers

■ Precision current sources

■ Current monitoring of notebook computers

■ Uninterruptible power supplies

■ High-end power supplies

Description

The TSC1031 measures a small differential

voltage on a high-side shunt resistor and

translates it into a ground-referenced output

voltage. The TSC1031’s dedicated schematic

eases the implementation of EMI filtering in harsh

environments. The gain is adjustable to 50 V/V or

100 V/V by a selection pin.

Wide input common-mode voltage range, low

quiescent current, and tiny TSSOP8 packaging

enable use in a wide variety of applications.

The input common-mode and power supply

voltages are independent. The common-mode

voltage can range from 2.9 to 70 V in the single-

supply configuration or be offset by an adjustable

voltage supplied on the Vcc- pin in the dual-

supply configuration.

With a current consumption lower than 360 µA

and a virtually null input leakage current in

standby mode, the power consumption in the

applications is minimized.

SO-8

(Plastic package)

TSSOP8

(Plastic package)

SEL

Gnd

Vcc-

Vcc+

Pin connections

(top view)

www.st.com

Summary of content (26 pages)

PAGE 1
TSC1031 High-voltage, high-side current sense amplifier Features ■ Independent supply and input common-mode voltages ■ Wide common-mode operating range: 2.9 to 70 V in single-supply configuration -2.1 to 65 V in dual-supply configuration ■ Wide common-mode surviving range: -16 to 75 V (reversed battery and load-dump conditions) ■ Supply voltage range: 2.7 to 5.
PAGE 2
Contents TSC1031 Contents 1 Application schematic and pin description . . . . . . . . . . . . . . . . . . . . . . 3 2 Absolute maximum ratings and operating conditions . . . . . . . . . . . . . 6 3 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 Electrical characteristics curves: current sense amplifier . . . . . . . . . 10 5 Parameter definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.
PAGE 3
TSC1031 1 Application schematic and pin description Application schematic and pin description The TSC1031 high-side current sense amplifier can be used in either single- or dual-supply mode. In the single-supply configuration, the TSC1031 features a wide 2.9 V to 70 V input common-mode range totally independent of the supply voltage. In the dual-supply range, the common-mode range is shifted by the value of the negative voltage applied on the Vccpin.
PAGE 4
Application schematic and pin description Figure 2. TSC1031 Dual-supply configuration schematic Vsense Iload Common-mode voltage: -2.
PAGE 5
TSC1031 Application schematic and pin description Figure 3. Common-mode versus supply voltage in dual-supply configuration Vicm common-mode voltage operating range Max = 70 V Max = 65 V Max = 60 V min = 2.9 V min = -2.1 V Vcc- = 0 V Vcc- = -5 V Single-supply min = -7.1 V Vcc- = -10 V Dual-supply AM04519 Table 1 describes the function of each pin. Their position is shown in the illustration on the cover page and in Figure 1 on page 3. Table 1.
PAGE 6
Absolute maximum ratings and operating conditions 2 TSC1031 Absolute maximum ratings and operating conditions Table 2. Absolute maximum ratings Symbol Vid Vin_sense Parameter Value Unit ±20 V -16 to 75 V -0.3 to Vcc++0.3 V -0.3 to Vcc++0.3 V -0.3 to 7 V 0 to 15 V -0.3 to Vcc++0.3 V -55 to 150 °C Maximum junction temperature 150 °C TSSOP8 thermal resistance junction to ambient 120 °C/W SO-8 thermal resistance junction to ambient 125 °C/W HBM: human body model(3) 2.
PAGE 7
TSC1031 3 Electrical characteristics Electrical characteristics The electrical characteristics given in the following tables are measured under the following test conditions unless otherwise specified. Table 4. Symbol ● Tamb = 25° C, Vcc+ = 5 V, Vcc- connected to Gnd (single-supply configuration). ● Vsense = Vp-Vm = 50 mV, Vm = 12 V, no load on Out, all gain configurations. ● Rf1, Rf2 and Rf3 resistors are short-circuited. Supply Parameter Test conditions Min. Typ. Max.
PAGE 8
Electrical characteristics Table 6. Symbol TSC1031 Output Parameter Test conditions Min. Typ. K1 Sense amplifier gain (K1 = Rg3/Rg1) K2 Current multiplier gain SEL= Gnd SEL= Vcc+ 2.5 5 Av Total gain (Av = 2.K1.K2) SEL= Gnd SEL= Vcc+ 50 100 Output voltage drift vs. T(1) Av = 50 V/V Tmin < Tamb < Tmax ΔVout/ΔT ΔVout/ΔIout Output stage load regulation Max. Unit 10 -10 mA < Iout <10 mA Iout sink or source current Av = 50 V/V, Tamb = 25° C 0.3 V/V ±240 ppm/°C ±1.
PAGE 9
TSC1031 Table 7. Electrical characteristics Frequency response Symbol Parameter Test conditions Min. Typ. Max. Unit Vsense = 10 mV to 100 mV, Cload = 47 pF ts Output settling to 1% of final value Av = 50 V/V 6 µs Av = 100 V/V 10 µs tSEL Output settling to 1% of final value Any change of state of SEL 1 µs trec Response to common-mode voltage change.
PAGE 10
Electrical characteristics curves: current sense amplifier 4 TSC1031 Electrical characteristics curves: current sense amplifier Unless otherwise specified, the test conditions for the following curves are: Figure 4. ● Tamb = 25°C, VCC = 5 V, Vsense = Vp - Vm = 50 mV, Vm = 12 V. ● No load on Out pin. Output voltage vs. Vsense Figure 5. Output voltage accuracy vs. Vsense 25 6 20 5 10 delta in (%) 4 Vout (V) Guaranteed accuracy vs.
PAGE 11
TSC1031 Electrical characteristics curves: current sense amplifier Figure 8. Vp pin input current vs. Vsense Figure 9. 40 35 T = 25 °C 30 T = -40 °C 20 Im (µA) Ip (µA) 25 15 10 5 T = 125 °C 0 -100 -50 0 50 Vn pin input current vs. Vsense 20 18 16 14 12 10 8 6 4 2 0 T = 25 °C T = 125 °C -100 100 T = -40 °C -50 Figure 10. Output stage low-state saturation voltage vs. output current (Vsense = -1 V) Figure 11.
PAGE 12
Electrical characteristics curves: current sense amplifier Figure 14. Bode diagram TSC1031 Figure 15. Power supply rejection ratio 30 50 45 20 40 35 10 PSRR (dB) Gain (dB) 30 0 -10 -20 20 15 10 5 0 -30 1.E+03 25 1.E+04 1.E+05 1.E+06 1.E+07 1.E+01 Figure 16. Noise Level 120 Noise level (nv/sqrt(Hz)) 100 80 60 40 20 0 Frequency (Hz) 12/26 1.E+02 1.E+03 1.E+04 Frequency (Hz) Frequency (Hz) Doc ID 16875 Rev 2 1.E+05 1.
PAGE 13
TSC1031 Parameter definitions 5 Parameter definitions 5.1 Common mode rejection ratio (CMR) The common mode rejection ratio (CMR) measures the ability of the current sensing amplifier to reject any DC voltage applied on both inputs Vp and Vm. The CMR is referred back to the input so that its effect can be compared with the applied differential signal. The CMR is defined by the formula: ΔV out CMR = – 20 ⋅ log -----------------------------ΔV icm ⋅ Av 5.
PAGE 14
Parameter definitions TSC1031 Figure 17. Vout versus Vsense characteristics: detail for low Vsense values Vout Vout_1 Vout_2 Vsense Vos Vsense2 Vsense1 AM04520 The values of Vsense1 and Vsense2 used for the input offset calculations are detailed in Table 9. Table 9.
PAGE 15
TSC1031 Output voltage drift versus temperature The output voltage drift versus temperature is defined as the maximum variation of Vout with respect to its value at 25° C over the temperature range. It is calculated as follows: ΔV out V out ( T amb ) – V out ( 25° C ) ----------------- = max -------------------------------------------------------------------------ΔT T amb – 25° C with Tmin < Tamb < Tmax. Figure 18 provides a graphical definition of the output voltage drift versus temperature.
PAGE 16
Parameter definitions 5.5 TSC1031 Input offset drift versus temperature The input voltage drift versus temperature is defined as the maximum variation of Vos with respect to its value at 25° C over the temperature range. It is calculated as follows: ΔV os V os ( T amb ) – V os ( 25° C ) --------------- = max --------------------------------------------------------------------ΔT T amb – 25° C with Tmin < Tamb < Tmax. Figure 19. provides a graphical definition of the input offset drift versus temperature.
PAGE 17
TSC1031 Parameter definitions Figure 20. Vout vs. Vsense theoretical and actual characteristics Vout Actual Ideal Vout accuracy for Vsense = 5 mV Vsense 5 mV AM04521 The output voltage accuracy, expressed as a percentage, can be calculated with the following formula, abs ( V out – ( Av ⋅ V sense ) ) ΔV out = -------------------------------------------------------------------------Av ⋅ V sense with 50 V/V or 100 V/V depending on the configuration of the SEL pin.
PAGE 18
Maximum permissible voltages on pins 6 TSC1031 Maximum permissible voltages on pins The TSC1031 can be used in either single or dual supply configuration. The dual-supply configuration is achieved by disconnecting Vcc- and Gnd, and connecting Vcc- to a negative supply. Figure 21 illustrates how the absolute maximum voltages on input pins Vp and Vm are referred to the Vcc- potential, while the maximum voltages on the positive supply pin, gain selection pins and output pins are referred to the Gnd pin.
PAGE 19
TSC1031 Application information The TSC1031 can be used to measure current and to feed back the information to a microcontroller. Figure 22. Typical application Vsense Iload Common-mode voltage: 2.9 V to 70 V Rsense load 7 Application information Rf1 Rf2 Vp Vm 5V Vcc Rg1 5K Vcc+ Rg2 SEL Sense amplifier Current multiplier K2 2.
PAGE 20
Application information TSC1031 The current multiplier gain K2 can be set to 2.5 or 5 depending on the voltage applied on the SEL pin. Since they define the full-scale output range of the application, the Rsense resistor and the amplification gain Av are important parameters and must therefore be selected carefully. The TSC1031’s dedicated schematic eases the implementation of EMI filtering in harsh environments.
PAGE 21
TSC1031 8 Package information Package information In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK® packages, depending on their level of environmental compliance. ECOPACK® specifications, grade definitions and product status are available at: www.st.com. ECOPACK® is an ST trademark.
PAGE 22
Package information 8.1 TSC1031 SO-8 package information Figure 23. SO-8 package mechanical drawing Table 10. SO-8 package mechanical data Dimensions Ref. Millimeters Min. Typ. A Max. Min. Typ. 1.75 0.25 Max. 0.069 A1 0.10 A2 1.25 b 0.28 0.48 0.011 0.019 c 0.17 0.23 0.007 0.010 D 4.80 4.90 5.00 0.189 0.193 0.197 E 5.80 6.00 6.20 0.228 0.236 0.244 E1 3.80 3.90 4.00 0.150 0.154 0.157 e 0.004 0.010 0.049 1.27 0.050 h 0.25 0.50 0.010 0.020 L 0.40 1.
PAGE 23
TSC1031 8.2 Package information TSSOP-8 package information Figure 24. TSSOP8 package mechanical drawing Table 11. TSSOP8 package mechanical data Dimensions Ref. Millimeters Min. Typ. A Inches Max. Min. Typ. 1.20 A1 0.05 A2 0.80 b Max. 0.047 0.15 0.002 1.05 0.031 0.19 0.30 0.007 0.012 c 0.09 0.20 0.004 0.008 D 2.90 3.00 3.10 0.114 0.118 0.122 E 6.20 6.40 6.60 0.244 0.252 0.260 E1 4.30 4.40 4.50 0.169 0.173 0.177 e 0.65 k 0° L 0.45 L1 aaa 1.00 0.
PAGE 24
Ordering information TSC1031 9 Ordering information Table 12. Order codes Part number Temperature range TSC1031IPT Package Packaging Marking TSSOP8 Tape & reel 1031I SO-8 Tape & reel TSC1031I TSSOP8(1) Tape & reel 1031Y Tape & reel TSC1031Y -40°C, +125°C TSC1031IDT TSC1031IYPT TSC1031IYDT -40°C, +125°C Automotive grade SO-8 (2) 1.
PAGE 25
TSC1031 10 Revision history Revision history Table 13. Document revision history Date Revision 04-Jan-2010 1 Initial release. 2 Added Chapter 4: Electrical characteristics curves: current sense amplifier. Changed Figure 4 to Figure 16. Modified Figure 22: Typical application. Added automotive grade qualification for SO-8 package in Table 12: Order codes.
PAGE 26
TSC1031 Please Read Carefully: Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale.