In this work, an ASIC (application specific integrated circuits) transducer circuit for field modulated giant magnetoresistance (GMR) sensors was designed and fabricated using a 0.18-μm CMOS process. The transducer circuits consist of a frequency divider, a digital phase shifter, an instrument amplifier, and an analog mixer. These comprise a mix of analog and digital circuit techniques. The compact chip size of 1.5 mm × 1.5 mm for both analog and digital parts was achieved using the TSMC18 1P6M (1-polysilicon 6-metal) process design kit, and the characteristics of the system were simulated using an HSpice simulator. The output of the transducer circuit is the result of the first harmonic detection, which resolves the modulated field using a phase sensitive detection (PSD) technique and is proportional to the measured magnetic field. When the dual-bridge GMR sensor is driven by the transducer circuit with a current of 10 mA at 10 kHz, the observed sensitivity of the field sensor is 10.2 mV/V/Oe and the nonlinearity error was 3% in the linear range of ±1 Oe. The performance of the system was also verified by rotating the sensor system horizontally in earth’s magnetic field and recording the sinusoidal output with respect to the azimuth angle, which exhibits an error of less than ±0.04 Oe. These results prove that the ASIC transducer is suitable for driving the AC field modulated GMR sensors applied to geomagnetic measurement.

1.
J.
Lenz
and
S.
Edelstein
,
IEEE Sens. J.
6
(
3
),
631
649
(
2006
).
2.
P.
Ripka
and
K.
Závěta
, in
Handbook of Magnetic Materials
, edited by
K. H. J.
Buschow
(
Elsevier
,
2009
), Vol. 18, pp.
347
420
.
3.
P.
Ripka
and
M.
Janosek
,
IEEE Sens. J.
10
(
6
),
1108
1116
(
2010
).
4.
K.-W.
Na
,
J.
Yuan
,
J.-H.
Ji
, and
S.-O.
Choi
,
J. Appl. Phys.
99
(
8
),
08M306
(
2006
).
5.
M.
Butta
,
P.
Ripka
,
J. P.
Navarrete
, and
M.
Vazquez
,
IEEE Trans. Magn.
46
(
2
),
532
535
(
2010
).
6.
C. C.
Lu
,
W. S.
Huang
,
Y. T.
Liu
, and
J. T.
Jeng
,
IEEE Trans. Magn.
47
(
10
),
3752
3755
(
2011
).
7.
C.-C.
Lu
and
J.
Huang
,
Sensors
15
(
6
),
14727
(
2015
).
8.
A.
Boukhenoufa
,
C. P.
Dolabdjian
, and
D.
Robbes
,
IEEE Sens. J.
5
(
5
),
916
923
(
2005
).
9.
D.
Flynn
,
Sens. Actuators, A
50
(
3
),
187
190
(
1995
).
10.
P.
Ripka
,
M.
Tondra
,
J.
Stokes
, and
R.
Beech
,
Sens. Actuators, A
76
(
1–3
),
225
230
(
1999
).
11.
M.
Vopálenský
,
P.
Ripka
, and
A.
Platil
,
Sens. Actuators, A
106
(
1–3
),
38
42
(
2003
).
12.
J. R.
Petta
,
T.
Ladd
, and
M. B.
Weissman
,
IEEE Trans. Magn.
36
(
4
),
2057
2061
(
2000
).
13.
N. A.
Stutzke
,
S. E.
Russek
,
D. P.
Pappas
, and
M.
Tondra
,
J. Appl. Phys.
97
(
10
),
10Q107
(
2005
).
14.
K. M. H.
Lenssen
,
D. J.
Adelerhof
,
H. J.
Gassen
,
A. E. T.
Kuiper
,
G. H. J.
Somers
, and
J. B. A. D.
van Zon
,
Sens. Actuators, A
85
(
1–3
),
1
8
(
2000
).
15.
E. W.
Hill
,
IEEE Trans. Magn.
36
(
5
),
2785
2787
(
2000
).
16.
M.
Tondra
,
J. M.
Daughton
,
D.
Wang
,
R. S.
Beech
,
A.
Fink
, and
J. A.
Taylor
,
J. Appl. Phys.
83
(
11
),
6688
6690
(
1998
).
17.
A.
Jander
,
C. A.
Nordman
,
A. V.
Pohm
, and
J. M.
Anderson
,
J. Appl. Phys.
93
(
10
),
8382
8384
(
2003
).
18.
M.
Tondra
,
A.
Jander
,
C. A.
Nordman
,
J.
Anderson
,
Z.
Qian
, and
D.
Wang
,
Proc. SPIE
5090
,
208
213
(
2003
).
19.
D. C.
Leitão
,
J. P.
Amaral
,
S.
Cardoso
, and
C.
Reig
, in
Giant Magnetoresistance (GMR) Sensors: From Basis to State-of-the-Art Applications
(
Springer Berlin Heidelberg
,
Berlin, Heidelberg
,
2013
), pp.
31
45
.
20.
See http://www.nobelprize.org/nobel_prizes/physics/laureates/2007/ for The Nobel Prize in Physics 2007, (Nobelprize.org Nobel Media AB 2014), web Avai1able: October 2016.
21.
M.
Vopálenský
,
P.
Ripka
,
J.
Kubík
, and
M.
Tondra
,
Sens. Actuators, A
110
(
1–3
),
254
258
(
2004
).
22.
J. T.
Jeng
,
T. Y.
Hsu
, and
C. C.
Lu
,
IEEE Trans. Magn.
47
(
10
),
3538
3541
(
2011
).
23.
J.-T.
Jeng
,
T.-Y.
Hsu
, and
C.-C.
Lu
,
presented at the Mechanical and Electronics Engineering (ICMEE), 2010 2nd International Conference on, Kyoto, Japan
(
IEEE
,
2010
), pp.
210
212
.
24.
J.-T.
Jeng
,
T.-Y.
Xu
,
C.-C.
Lu
, and
B.-R.
Cai
,
J. Phys.: Conf. Ser.
266
(
1
),
012034
(
2011
).
25.
V. S.
Luong
,
C. H.
Chang
,
J. T.
Jeng
,
C. C.
Lu
,
J. H.
Hsu
, and
C. R.
Chang
,
IEEE Trans. Magn.
50
(
11
),
1
4
(
2014
).
26.
V. S.
Luong
,
J. T.
Jeng
,
J. H.
Hsu
,
C. R.
Chang
, and
C. C.
Lu
,
IEEE Trans. Magn.
52
(
7
),
1
4
(
2016
).
27.
J.-T.
Jeng
and
T.-Y.
Hsu
,
Rev. Sci. Instrum.
82
(
3
),
034701
(
2011
).
28.
J. T.
Jeng
,
C. Y.
Chiang
,
C. H.
Chang
, and
C. C.
Lu
,
IEEE Trans. Magn.
50
(
1
),
1
4
(
2014
).
29.
C.-Y.
Chiang
,
J.-T.
Jeng
,
B.-L.
Lai
,
V. S.
Luong
, and
C.-C.
Lu
,
J. Appl. Phys.
117
(
17
),
17A321
(
2015
).
30.
V. S.
Luong
,
J. T.
Jeng
,
B. L.
Lai
,
J. H.
Hsu
,
C. R.
Chang
, and
C. C.
Lu
,
IEEE Trans. Magn.
51
(
11
),
1
4
(
2015
).
31.
M.
Kashmiri
,
W.
Kindt
,
F.
Witte
,
R.
Kearey
and
D.
Carbonell
,
presented at the 2015 IEEE International Solid-State Circuits Conference - (ISSCC) Digest of Technical Papers, San Francisco, CA, USA
(
IEEE
,
2015
) pp.
490
493
.
32.
P. M.
Drljaca
,
P.
Kejik
,
F.
Vincent
,
D.
Piguet
, and
R. S.
Popovic
,
IEEE Sens. J.
5
(
5
),
909
915
(
2005
).
You do not currently have access to this content.