W

DIFF

REF

BIAS

V

V

2 V



DIFF(MAX)

DIFF (MIN)

6

REF

V

V

Tracking Error

10

(ppm)

V

Temperature Range



§

·

x

¨

¸

x

©

¹

+

+

e-Trim

e-Trim

+

-

-

+

+

REF1925, REF1930, REF1933, REF1941

www.ti.com

SBOS697 – SEPTEMBER 2014

9 Detailed Description

9.1 Overview

Block Diagram section provides a block diagram of the basic band-gap topology and the two buffers used to

which has a negative temperature coefficient. The resulting band-gap output voltage is almost independent of

implemented during the final steps of manufacturing after the plastic molding process. This method minimizes the

influence of inherent transistor mismatch, as well as errors induced during package molding. e-Trim is

9.2 Functional Block Diagram

9.3 Feature Description

Most single-supply systems require an additional stable voltage in the middle of the analog-to-digital converter

the same band-gap voltage as shown in the Functional Block Diagram section. Hence, both outputs track each

other over the full temperature range of –40°C to 125°C with an accuracy of 7 ppm/°C (max). The tracking

accuracy increases to 6 ppm/°C (max) when the temperature range is limited to –40°C to 85°C. The tracking

error is calculated using the box method, as described by Equation 2:

where

•

(2)

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Product Folder Links: REF1925 REF1930 REF1933 REF1941