User manual

Atmel AVR32924: UC3-L0 XPLAINED Hardware User’s Guide [APPLICATION NOTE]
32156C−AVR−06/2013
18
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4
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5
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D D
C C
B B
A A
5
Analog. SchDoc
576/ 4/ 2013 5: 16: 54 PM
UC3- L0 XPLAI NED
ATM EL Nor way
Vest r e Rost en 79
N- 7075 TI LLER
NO RW A Y
PAG E: o f
TI TLE:
Docum ent num ber :
Rev ision: 4
Da t e :
*
*
*
NTC Tem per at ur e Sensor
GND
VCC_P3 V3
100k
R400
12
NCP18WF104J03RB
R4 0 1
NT C_ O U T P UT
L ow pass RC Filt er
GND
FI LTER_I NPUT FI LTER_O UTPUT
GRB
1
2 3
4
67-23/ R6G 6B6C- B38/ 2T
D4 0 0
VCC_P3 V3
G RB
1
2 3
4
67-23/ R6G 6B6C- B38/ 2T
D4 0 0
VCC_P3 V3
RGBL ED
GNDGND
Clock c ir cuit r y
GND
XC400
Epson FC- 145 cr yst al.
22p
C4 0 1
22p
C400
XI N3 2
XO UT3 2
XTAL
XTAL
J400
SM D- ST RAP_CL O SED
J401
SM D- ST RA P _ CL O S E D
J402
SM D- ST RAP_CL O SED
This s t r ap wit h SM D pads can be used
t o place a r esist or in t he XO UT signal
in or der t o measur e t he dr ive le v e l a n d
t h e o s c illa t o r allo w a n c e .
By default t hese st r aps ar e closed and
not hing is mount ed on t he pads.
1u
C4 0 2
1k
R405
1
23
2N7002
Q 400
G REEN
RED
BL UE
RG BL E D
RG BL ED
1
23
2N7002
Q 401
1
23
2N7002
Q 402
GND
GND
GND
100k
R406
100k
R407
100k
R408
62R
R403
150R
R402
180R
R404
100k NTC Tem per at ur e Sensor .
O ut put will b e Vc c / 2 a t 2 5 C.
B( 25/ 80) = 4255K
B( 25/ 85) = 4260K
B( 25/ 100) = 4282K
Be t a - f o r m u la:
R1 = R2 * e ^ ( B/ T1 -B/ T2 )
Ex . B( 25/ 80) :
R = 100k * e^( 4255/ T1 - 4255/ 25)
1. or der RC Lowpass filt e r w it h
cut -of f fr equency at appr oxim a t e ly
1k Hz.
To have cons t ant DC values wit h low
r ipple, t he capacit or / r esist or values
should be chosen t o t he min im u m
cut -of f fr equency.
Cr y st al dat asheet :
Load capacit ance CL = 12. 5 pF
ESR 70 k O h m M a x.
Fr equency t oler anc e 20ppm
Dr iv e Level 0. 5uW
AT32UC3L 0 dat as heet :
Int er nal equiv alent capacit ance of t he device is Ci = 2 pF
The package and pin capacit ance is neglig ib le ( < 1 p F )
C = 2 ( CL - Ci ) = 2 ( 12. 5 - 2) pF = 21 pF
Select ed value is 22pF