INA193AMDBVREP datasheet(9/20 Pages) TI1

9 / 20 page

www.ti.com

Normal Case 1: VSENSE ≥ 20 mV, VCM ≥ VS

G +

OUT1 * VOUT2

100 mV * 20 mV

(1)

OSRTI (Referred−To−Input)

OUT1

* 100 mV

(2)

Normal Case 2: VSENSE ≥ 20 mV, VCM < VS

Low VSENSE Case 1: VSENSE < 20 mV, –16 V ≤ VCM < 0; and Low VSENSE Case 3: VSENSE < 20 mV,

INA193A-EP,, INA194A-EP,, INA195A-EP

INA196A-EP, INA197A-EP, INA198A-EP

SBOS400 – MAY 2007

APPLICATION INFORMATION (continued)

This section addresses the accuracy of these specific operating regions:

Normal Case 1:

VSENSE ≥ 20 mV, VCM ≥ VS

Normal Case 2:

VSENSE ≥ 20 mV, VCM < VS

Low VSENSE Case 1: VSENSE < 20 mV, –16 V ≤ VCM < 0

Low VSENSE Case 2: VSENSE < 20 mV, 0 V ≤ VCM ≤ VS

Low VSENSE Case 3: VSENSE < 20 mV, VS < VCM ≤ 80 V

This region of operation provides the highest accuracy. Here, the input offset voltage is characterized and

measured using a two-step method. First, the gain is determined by (Equation 1).

Where:

VOUT1 = Output voltage with VSENSE = 100 mV

VOUT2 = Output voltage with VSENSE = 20 mV

The offset voltage is then measured at VSENSE = 100 mV and referred to the input (RTI) of the current shunt

monitor, as shown in (Equation 2).

In the Typical Characteristics, the Output Error vs Common-Mode Voltage curve shows the highest accuracy for

the this region of operation. In this plot, VS = 12 V; for VCM ≥ 12 V, the output error is at its minimum. This case

is also used to create the VSENSE ≥ 20 mV output specifications in the Electrical Characteristics table.

This region of operation has slightly less accuracy than Normal Case 1 as a result of the common-mode

operating area in which the part functions, as seen in the Output Error vs Common-Mode Voltage curve. As

noted, for this graph VS = 12 V; for VCM < 12 V, the Output Error increases as VCM becomes less than 12 V, with

a typical maximum error of 0.005% at the most negative VCM = –16 V.

VS < VCM ≤ 80 V

Although the INA193A–INA198A family of devices are not designed for accurate operation in either of these

regions, some applications are exposed to these conditions; for example, when monitoring power supplies that

are switched on and off while VS is still applied to the INA193A–INA198A. It is important to know what the

behavior of the devices will be in these regions.

As VSENSE approaches 0 mV, in these VCM regions, the device output accuracy degrades. A larger-than-normal

offset can appear at the current shunt monitor output with a typical maximum value of VOUT = 300 mV for

VSENSE = 0 mV. As VSENSE approaches 20 mV, VOUT returns to the expected output value with accuracy as

specified in the Electrical Characteristics. Figure 2 illustrates this effect using the INA195A and INA198A

(Gain = 100).

Submit Documentation Feedback

INA193AMDBVREP 数据表(PDF) 9 Page - Texas Instruments

INA193AMDBVREP 数据表(HTML) 9 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

数据表下载