ST TSC1021 User Manual

Features
Wide common-mode operating range
independent of supply: 2.8 to 30 V
Wide common-mode surviving range:
Maximum input offset voltage:
– ±1.5 mV for T – ±2.3 mV for -40
Maximum total output voltage error:
– ±1.5% for T – ±2.5% for -40°C < T
Maximum variation over temperature:
–dV –dV
Low current consumption: I
-40 to 125°C operating temperature range
Internally fixed gain: 20 V/V, 50 V/V
EMI filtering
/dT = 8 µV/°C
os
/dT = 100 ppm/°C
out
amb
amb
= 25°C
°C < T
= 25°C
amb
< 125°C
amb
< 125°C
max = 300 µA
CC
Applications
Automotive current monitoring
Notebook computers
Server power supplies
Telecom equipment
Industrial SMPS
Current sharing
LED current measurement
TSC1021
High-side current sense amplifier
TSSOP8
(Plastic package)
Description
The TSC1021 measures a small differential voltage on a high-side shunt resistor and translates it into a ground-referenced output voltage.
The TSC1021 has been specifically designed to deal with automotive conditions: load-dump protection up to 60 V, reverse-battery protection up to -32 V, ESD protection up to 4 kV and internal filtering for EMI performance.
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 ratings while the TSC1021 can be supplied by a 5 V independent supply line.
The TSC1021 is housed in a tiny TSSOP8 package and integrates a buffer that provides low impedance output to ease interfacing and avoid accuracy losses. The overall device current consumption is lower than 300 µA.
September 2010 Doc ID 17857 Rev 1 1/12
www.st.com
12
Application diagram TSC1021

1 Application diagram

The TSC1021 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 (V

Figure 1. Application schematic: high-line current sensing

Vsense
Iload
Common-mode range
R
sense
CC
).
Supply voltage
Vcc
Rg3
Gnd
Vp
Rg1
Vm
Rg2
Out
V
out
= Av.V
sense
AM06135
2/12 Doc ID 17857 Rev 1
TSC1021 Pin configuration

2 Pin configuration

Figure 2. Pin connections (top view)

Vm
NC
Gnd
Out
1
2
3
4
Vp
8
NC
7
Vcc
6
NC
5
Ta bl e 1 describes the function of each pin. Their position is shown in the illustration on the
cover page and in Figure 1 above.
A1

Table 1. Pin description

Pin number Symbol Type Function
1V
m
Analog input
3 Gnd Power supply Ground line
4 Out Analog output Buffered output of the current sensing amplifier
6V
8V
CC
p
Power supply Positive power supply line
Analog input
Connection for the external sense resistor. The measured current exits the shunt on the V
side.
m
Connection for the external sense resistor. The measured current enters the shunt on the V
side.
p
Doc ID 17857 Rev 1 3/12
Absolute maximum ratings and operating conditions TSC1021

3 Absolute maximum ratings and operating conditions

Table 2. Absolute maximum ratings

Symbol Parameter Value Unit
V
id
V
V
1
T
stg
T
R
thja
ESD
1. Voltage values are measured with respect to the GND 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 and package are charged together to the specified voltage and then discharged directly to ground.

Table 3. Operating conditions

Input pins differential voltage (Vp-Vm)±20V
Current sensing input pin voltages (Vp and Vm)
i
Voltage for Vcc, Out pins
(1)
(1)
-32 to 60 V
-0.3 to 7 V
Storage temperature -65 to 150 °C
Maximum junction temperature 150 °C
j
TSSOP8 thermal resistance junction to ambient 120 °C/W
HBM: human body model for V
HBM: human body model
MM: machine model
CDM: charged device model
(2)
(3)
(4)
and Vm pins
p
(2)
4kV
2kV
250 V
1.5 kV
Symbol Parameter Value Unit
V
T
V
CC
oper
icm
DC supply voltage from T
Operational temperature range (T
min
to T
max
min
to T
Common mode voltage range (Vm and Vp pins voltages)
4/12 Doc ID 17857 Rev 1
3.5 to 5.5 V
) -40 to 125 °C
max
2.8 to 30 V
TSC1021 Electrical characteristics

4 Electrical characteristics

The electrical characteristics given in the following tables are measured under the following test conditions unless otherwise specified: T V
= 12 V, no load on Out, all gain configurations.
m

Table 4. Supply

Symbol Parameter Test conditions Min. Typ. Max. Unit
I
CC
I
CC1

Table 5. Electrical performances

Symbol Parameter Test conditions Min. Typ. Max. Unit
Total supply current
Total supply current
= 0 V
V
sense
-40°C < T
V
= 50 mV
sense
-40°C < T
amb
amb
= 25°C, V
amb
< 125°C
< 125°C
CC
= 5 V, V
= Vp-Vm = 50 mV,
sense
300 µA
450 µA
DC common-mode rejection
DC CMR
Variation of V
(1)
to input
versus Vm referred
out
AC common mode rejection
AC CMR
Variation of V to input (peak-to-peak voltage
versus Vm referred
out
variation)
Supply voltage rejection Variation of V
Input offset voltage
os
versus V
out
(1)
CC
(1)
/dT Input offset drift vs. T -40°C< T
/dT Output voltage drift vs. T -40°C< T
Input leakage current
lk
Input bias current
ib
Gain (variation of V
Total output voltage accuracy
out
Total output voltage accuracy
out
Total output voltage accuracy
out
out
versus V
sense
)
(2)
(2)
(2)
dV
dV
SVR
V
os
out
I
I
Av
ΔV
ΔV
ΔV
2.8 V< Vm < 30 V
-40°C < T
2.8 V< V
amb
< 30 V
m
< 125°C
DC to 1 kHz sine wave
3.5 V< VCC < 5.5 V
-40°C< T
< 125°C
amb
2.8 V< Vm < 30 V T
= 25° C
amb
-40°C < T
V
= 0 V
CC
-40°C < T
V
sense
-40°C < T
< 125°C
amb
< 125°C 8 µV/°C
amb
< 125°C 100 ppm/°C
amb
< 125°C
amb
= 0 V
< 125°C
amb
TSC1021A TSC1021B
V
= 50 mV
sense
T
= 25° C
amb
T
< T
amb
= 100 mV
= 25° C
< T
amb
= 20 mV
= 25° C
< T
amb
< T
< T
< T
max
max
max
min
V
sense
T
amb
T
min
V
sense
T
amb
T
min
90 105 dB
75 dB
80 95 dB
±1.5
mV
±2.3
A
A
20 50
±1.5
V/V
%
±2.5
±1.5
%
±2.5
±7
%
±9
Doc ID 17857 Rev 1 5/12
Electrical characteristics TSC1021
Table 5. Electrical performances
Symbol Parameter Test conditions Min. Typ. Max. Unit
V
= 10 mV
ΔV
ΔV
out
V
V
1. See Chapter 5: Parameter definitions.
2. Output voltage accuracy is the difference with the expected theoretical output voltage V See Chapter 5: Parameter definitions for a more detailed definition.

Table 6. Dynamic performances

Total output voltage accuracy
out
/ΔI
Output stage load regulation
out
Out high level saturation voltage
oh
Voh=Vcc-V
Out low level saturation voltage
ol
out
(2)
Symbol Parameter Test conditions Min. Typ. Max. Unit
sense
= 25° C
T
amb
T
< T
amb
out
= 1 V, I
= 25° C
amb
= -1 V, I
= 25° C
amb
< T
max
<5 mA
= 1 mA
out
< 125°C
out
< 125°C
min
-5 mA < I sink or source current
I
out
V
sense
T
amb
-40°C< T
V
sense
T
amb
-40°C< T
= 1 mA
out-th
±12 ±15
±0.4 ±2 mV/mA
90 135
185
80 125
165
= Av x V
sense
.
%
mV
mV
ts V
settling to 1% final value
out
SR Slew rate V
BW 3 dB bandwidth C
e
Equivalent input noise voltage f = 1 kHz 50 nV/√ Hz
N
V
= 10 mV to 100 mV,
sense
C
= 47 pF
load
= 10 mV to 100 mV 0.3 0.45 V/µs
sense
= 47 pF 800 kHz
load
s
6/12 Doc ID 17857 Rev 1
TSC1021 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 V back to the input so that its effect can be compared with the applied differential signal. The CMR is defined by the formula:
ΔV
CMR 20
------------------------------log= ΔV
out
icm

5.2 Supply voltage rejection ratio (SVR)

The supply-voltage rejection ratio (SVR) measures the ability of the current-sensing amplifier to reject any variation of the supply voltage V input so that its effect can be compared with the applied differential signal. The SVR is defined by the formula:
Av
and Vm. The CMR is referred
p
. The SVR is referred back to the
CC
ΔV
out
SVR 20
---------------------------log= ΔVccAv

5.3 Gain (Av) and input offset voltage (Vos)

The input offset voltage is defined as the intersection between the linear regression of the V
vs. the V
out
V V
= V
sense
can be calculated with the following formula.
os
sense1
curve with the X-axis. If V
sense
= 50 mV and V
V
os
V
sense1
out2
is the output voltage with
out1
is the output voltage with V
V
⎛⎞
------------------------------------------------
=
⎝⎠
sense1Vsense2
V
out1Vout2
V
out1

5.4 Output voltage drift versus temperature

The output voltage drift versus temperature is defined as the maximum variation of V respect to its value at 25°C, over the temperature range. It is calculated as follows:
ΔV
out
-----------------max
ΔT
=
V
Tamb()V
out
------------------------------------------------------------------------- -
Tamb 25° C
out
25° C()
sense
= V
sense2
= 5 mV, then
with
out
with T
min
< T
amb
< T
max
.
Doc ID 17857 Rev 1 7/12
Parameter definitions TSC1021

5.5 Output voltage accuracy

The output voltage accuracy is the difference between the actual output voltage and the theoretical output voltage. Ideally, the current sensing output voltage should be equal to the input differential voltage multiplied by the theoretical gain, as in the following formula.
V
out-th
Av V
=
sense
The actual value is very slightly different, mainly due to the effects of:
the input offset voltage V
the non-linearity,
the voltage saturation of V
,
os
and VOH.
OL
The output voltage accuracy, expressed as a percentage, can be calculated with the following formula.
ΔV
out
abs V
---------------------------------------------------------------------------=
out
Av V
Av V
()()
sense
sense
with Av = 20 V/V for TSC1021A and Av = 50 V/V for TSC1021B.
8/12 Doc ID 17857 Rev 1
TSC1021 Package information

6 Package information

In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK specifications, grade definitions and product status are available at: www.st.com. ECOPACK
®
packages, depending on their level of environmental compliance. ECOPACK®
®
is an ST trademark.

Figure 3. TSSOP8 package mechanical drawing

Table 7. TSSOP8 package mechanical data

Dimensions
Ref.
Min. Typ. Max. Min. Typ. Max.
A1.200.047
A1 0.05 0.15 0.002 0.006
A2 0.80 1.00 1.05 0.031 0.039 0.041
b 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 0.0256
k0° 8°0° 8°
L 0.45 0.60 0.75 0.018 0.024 0.030
L1 1 0.039
aaa 0.10 0.004
Millimeters Inches
Doc ID 17857 Rev 1 9/12
Ordering information TSC1021

7 Ordering information

Table 8. Order codes

Part number Temperature range Package Packaging Marking Gain
TSC1021AIPT
O21AI 20
-40°C, +125°C
TSC1021BIPT O21BI 50
TSSOP8 Tape & reel
TSC1021AIYPT
TSC1021BIYPT O21BY 50
1. Qualification and characterization according to AEC Q100 and Q003 or equivalent, advanced screening according to AEC Q001 & Q 002 or equivalent are ongoing.
-40°C, +125°C
Automotive grad
(1)
e
O21AY 20
10/12 Doc ID 17857 Rev 1
TSC1021 Revision history

8 Revision history

Table 9. Document revision history

Date Revision Changes
23-Sep-2010 1 Initial release.
Doc ID 17857 Rev 1 11/12
TSC1021
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.
Purchasers are solely responsible for the choice, selection and use of the ST products and services described herein, and ST assumes no liability whatsoever relating to the choice, selection or use of the ST products and services described herein.
No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. If any part of this document refers to any third party products or services it shall not be deemed a license grant by ST for the use of such third party products or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoever of such third party products or services or any intellectual property contained therein.
UNLESS OTHERWISE SET FORTH IN ST’S TERMS AND CONDITIONS OF SALE ST DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY WITH RESPECT TO THE USE AND/OR SALE OF ST PRODUCTS INCLUDING WITHOUT LIMITATION IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION), OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT.
UNLESS EXPRESSLY APPROVED IN WRITING BY AN AUTHORIZED ST REPRESENTATIVE, ST PRODUCTS ARE NOT RECOMMENDED, AUTHORIZED OR WARRANTED FOR USE IN MILITARY, AIR CRAFT, SPACE, LIFE SAVING, OR LIFE SUSTAINING APPLICATIONS, NOR IN PRODUCTS OR SYSTEMS WHERE FAILURE OR MALFUNCTION MAY RESULT IN PERSONAL INJURY, DEATH, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE. ST PRODUCTS WHICH ARE NOT SPECIFIED AS "AUTOMOTIVE GRADE" MAY ONLY BE USED IN AUTOMOTIVE APPLICATIONS AT USER’S OWN RISK.
Resale of ST products with provisions different from the statements and/or technical features set forth in this document shall immediately void any warranty granted by ST for the ST product or service described herein and shall not create or extend in any manner whatsoever, any liability of ST.
ST and the ST logo are trademarks or registered trademarks of ST in various countries.
Information in this document supersedes and replaces all information previously supplied.
The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners.
© 2010 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 - Philippines - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America
www.st.com
12/12 Doc ID 17857 Rev 1
Loading...