ST TSC101 User Manual

TSC101

High side current sense amplifier

Features

■Independent supply and input common-mode voltages

■Wide common-mode operating range: 2.8 to 30 V

■Wide common-mode surviving range: -0.3 to 60 V (load-dump)

■Wide supply voltage range: 4 to 24 V

■Low current consumption: ICC max = 300 µA

■Internally fixed gain: 20 V/V, 50 V/V or 100 V/V

■Buffered output

Applications

■Automotive current monitoring

■Notebook computers

■DC motor controls

■Photovoltaic systems

■Battery chargers

■Precision current sources

Description

The TSC101 measures a small differential voltage on a high-side shunt resistor and translates it into a ground-referenced output voltage. The gain is internally fixed.

Wide input common-mode voltage range, low quiescent current, and tiny SOT23 packaging enable use in a wide variety of applications.

L

SOT23-5

(Plastic package)

Pin connections

(top view)

Out 1		5	Vcc
Gnd	2
Vp	3	4	Vm

The input common-mode and power supply voltages are independent. The common-mode voltage can range from 2.8 to 30 V in operating conditions and up to 60 V in absolute maximum rating conditions.

The current consumption below 300 µA and the wide supply voltage range enable the power supply to be connected to either side of the current measurement shunt with minimal error.

March 2011

Doc ID 13313 Rev 3

1/18

www.st.com

Application schematics and pin description	TSC101

1 Application schematics and pin description

The TSC101 high-side current sense amplifier features a 2.8 to 30 V input common-mode range that is independent of the supply voltage. The main advantage of this feature is that it allows high-side current sensing at voltages much greater than the supply voltage (VCC).

Figure 1. Application schematics

6SENSE		)LOAD
TO T66
2SENSE
		LOAD
6P		6M
2G		2G
TO O66
6##

	2G
		/UT
		6OUTU T!VVX 6SENSE
	'ND

!-

Table 1 describes the function of each pin. The pin positions are shown in the illustration on the cover page and in Figure 1 above.

	Table 1.	Pin descriptions
	Symbol	Type	Function
	Out	Analog output	Output voltage, proportional to the magnitude of the sense voltage
			Vp-Vm.
	Gnd	Power supply	Ground line
	VCC	Power supply	Positive power supply line
	Vp	Analog input	Connection for the external sense resistor. The measured current
			enters the shunt on the Vp side.
	Vm	Analog input	Connection for the external sense resistor. The measured current
			exits the shunt on the Vm side.

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TSC101	Absolute maximum ratings and operating conditions

2 Absolute maximum ratings and operating conditions

Table 2.		Absolute maximum ratings
Symbol		Parameter				Value	Unit
Vid		Input pins differential voltage (Vp-Vm)				±60	V
V	i	Input pin voltages (V	p	and V	)(1)	-0.3 to 60	V
					m
VCC		DC supply voltage(1)				-0.3 to 25	V
V		DC output pin voltage(1)				-0.3 to V	V
out						CC
Tstg		Storage temperature				-55 to 150	°C
Tj		Maximum junction temperature				150	°C
Rthja		SOT23-5 thermal resistance junction to ambient				250	°C/W
		HBM: human body model(2)				2.5	kV
ESD		MM: machine model(3)				150	V
		CDM: charged device model(4)				1.5	kV

1.Voltage values are measured with respect to the ground pin.

2.Human body model: a 100 pF capacitor is charged to the specified voltage, then discharged through a 1.5kΩ resistor between two pins of the device. This is done for all couples of connected pin combinations while the other pins are floating.

3.Machine model: a 200 pF capacitor is charged to the specified voltage, then discharged directly between two pins of the device with no external series resistor (internal resistor < 5 Ω). This is done for all couples of connected pin combinations while the other pins are floating.

4.Charged device model: all pins plus package are charged together to the specified voltage and then discharged directly to the ground.

Table 3.	Operating conditions
Symbol	Parameter	Value	Unit
VCC	DC supply voltage from Tmin to Tmax	4.0 to 24	V
Toper	Operational temperature range (Tmin to Tmax)	-40 to 125	°C
Vicm	Common mode voltage range	2.8 to 30	V

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Electrical characteristics						TSC101
3	Electrical characteristics
Table 4.	Supply(1)
Symbol	Parameter	Test conditions	Min.	Typ.	Max.	Unit
ICC	Total supply current	Vsense = 0 V		165	300	µA
		Tmin < Tamb < Tmax

1.Unless otherwise specified, the test conditions are Tamb = 25°C, VCC = 12 V, Vsense = Vp-Vm = 50 mV, Vm = 12 V, no load on Out.

Table 5.	Input(1)
Symbol	Parameter	Test conditions	Min.	Typ.	Max.	Unit
	Common mode rejection	2.8 V < Vicm < 30 V
CMR	Variation of Vout versus Vicm		90	105		dB
		Tmin < Tamb < Tmax
	referred to input(2)
SVR	Supply voltage rejection	4.0 V < VCC < 24 V	90	105		dB
	(3)	Vsense = 30 mV
	Variation of Vout versus VCC	Tmin < Tamb < Tmax
V	(4)	Tamb = 25° C		±0.2	±1.5	mV
	Input offset voltage
os		Tmin < Tamb < Tmax		±0.9	±2.3
dVos/dT	Input offset drift vs. T	Tmin < Tamb < Tmax		-3		µV/°C
Ilk	Input leakage current	VCC = 0 V			1	µA
		Tmin < Tamb < Tmax
Iib	Input bias current	Vsense = 0 V		5.5	8	µA
		Tmin < Tamb < Tmax

1.Unless otherwise specified, the test conditions are Tamb = 25°C, VCC = 12 V, Vsense = Vp-Vm = 50 mV, Vm = 12 V, no load on Out.

2.See Section 4.1: Common mode rejection ratio (CMR) on page 11 for the definition of CMR.

3.See Section 4.2: Supply voltage rejection ratio (SVR) on page 11 for the definition of SVR.

4.See Section 4.3: Gain (Av) and input offset voltage (Vos) on page 11 for the definition of Vos.

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TSC101

Electrical characteristics

Table 6.

Output(1)

Symbol

Parameter

Test conditions

Min.

Typ.

Max.

Unit

TSC101A

20

Av

Gain

TSC101B

50

V/V

TSC101C

100

Av

Gain accuracy

Tamb = 25°C

±2.5

%

Tmin < Tamb < Tmax

±4.5

V

/

T

Output voltage drift vs. T(2)

T

< T

< T

max

0.4

mV/°C

out

min

amb

Vout/

Iout

Output stage load regulation

-10 mA < Iout <10 mA

3

4

mV/mA

Iout sink or source current

V

(3)

Vsense = 50 mV Tamb = 25° C

±2.5

%

Total output voltage accuracy

out

Tmin < Tamb < Tmax

±4.5

Vout

Total output voltage accuracy

Vsense = 100 mV Tamb = 25° C

±3.5

%

Tmin < Tamb < Tmax

±5

Vout

Total output voltage accuracy

Vsense = 20 mV Tamb = 25° C

±8

%

Tmin < Tamb < Tmax

±11

Vout

Total output voltage accuracy

Vsense = 10 mV Tamb = 25° C

±15

%

Tmin < Tamb < Tmax

±20

Isc-sink

Short-circuit sink current

Out connected to VCC,

30

60

mA

Vsense = -1 V

Isc-source

Short-circuit source current

Out connected to Gnd

15

26

mA

Vsense = 1 V

Output stage high-state saturation

Vsense = 1 V

Voh

voltage

0.8

1

V

Iout = 1 mA

Voh=VCC-Vout

Vol

Output stage low-state saturation

Vsense = -1 V

50

100

mV

voltage

Iout = 1 mA

1.Unless otherwise specified, the test conditions are Tamb = 25°C, VCC = 12 V, Vsense = Vp-Vm = 50 mV, Vm = 12 V, no load on Out.

2.See Output voltage drift versus temperature on page 12 for the definition.

3.Output voltage accuracy is the difference with the expected theoretical output voltage Vout-th = Av*Vsense. See Output voltage accuracy on page 13 for a more detailed definition.

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Electrical characteristics						TSC101
Table 7.	Frequency response(1)
Symbol	Parameter	Test conditions	Min.	Typ.	Max.	Unit
		Vsense = 10 mV to 100 mV
		Cload = 47 pF(2)		3
ts	Output settling to 1% final value	TSC101A				µs
		TSC101B		6
		TSC101C		10
SR	Slew rate	Vsense = 10 mV to 100 mV	0.55	0.9		V/µs
		Cload = 47 pF(2)
BW	3dB bandwidth	Vsense = 100 mV		500		kHz
		TSC101A		670
		TSC101B
				450
		TSC101C

1.Unless otherwise specified, the test conditions are Tamb = 25°C, VCC = 12 V, Vsense = Vp-Vm = 50 mV, Vm = 12 V, no load on Out.

2.For stability purposes, we do not recommend using a greater value of load capacitor.

Table 8.	Noise(1)
Symbol	Parameter	Test conditions	Min.	Typ.	Max.	Unit
	Total output voltage noise			50		nV/√
							Hz

1.Unless otherwise specified, the test conditions are Tamb = 25°C, VCC = 12 V, Vsense = Vp-Vm = 50 mV, Vm = 12 V, no load on Out.

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