D E M O C IRC U IT 1 3 0 4
Q U IC K S TA RT G U ID E
LTC 6 6 0 2 / LTC 6 6 0 3
P RO G RA M A B L E B A N D P A S S / L O W P A S S F IL T E R
D E S C R IP T IO N
Demonstration Circuit 1304A f
eatures tw o programmabl
e
f ter I the LTC6602 dual matched, bandpass f ter and
il Cs,
,
il
the LTC6603,dual matched,l pass f ter.
,
ow
il
DC1304A-
The DC1304A- A is for an LTC6602 and
DC1304A-
The DC1304A- B is for an LTC6603.
The LTC® 6602 is a dual programmabl bandpass f ter
,
e
il
and dif erential driver. The sel
f
ectivity of the LTC6602 is
ideal f f tering baseband tag signal in R FI systems.
or il
s
D
The LTC® 6603 is a dual programmabl l pass f ter f
,
e ow
il or
communications receivers and transmitters in TD-SCDM A,
W CDM A, CDM A2000, U M TS
and
802.11x systems. A
DC1304A-A or --B board has tw o pairs of SM A connectors
-
f dif erential inputs and tw o pairs of SM A connectors f
or f
or
dif erential outputs. The dif erential inputs can be AC cou-
f
f
pl or DC coupl O n board j
ed
ed.
umpers provide controlof an
LTC6602 or an LTC6603. The j
umper control settings are:
serialor paralelcontrol internalor externalcl
l
,
ock, gain and
bandw idth control and input AC or DC coupl
ing. An on
board mul
ti-turn potentiometer sets the val of the R BI
ue
AS
resistor that sets the I pow er suppl current and cl
C
y
ock
f
requency. PCB turrets provide f board connections to an
or
SPI master f a serialcontrolof I gain and bandw idth.
or
C
T h e L T C 6 6 0 2 B L O C K D IA G RA RA M
T h e L T C 6 6 0 3 B L O C K D IA RG A RA M
LTC6602 features:
G uaranteed Phase and G ain M atching Specs
Programmabl 5th O rder Low pass:40 kH z to 900 kH z
e
Programmabl 4th O rder H ighpass:4 kH z to 90 kH z
e
Programmabl G ain (0dB/
e
12dB/
24dB/
30dB)
Simpl Pin Programming or SPI I
e
nterf
ace
I
nput R ange Extends f
rom 0V to 5V
Low Vol
tage O peration:2.7V to 3.6V
Shutdow n and M ute M ode
4mm × 4mm Q FN Package
LTC6603 features:
G uaranteed Phase and G ain M atching Specs
Programmabl 9th O rder Low pass:24 kH z to 2.5 M H z
e
Programmabl G ain (0dB/
e
6dB/
12dB/
24dB)
Simpl Pin Programming or SPI I
e
nterf
ace
I
nput R ange Extends f
rom 0V to 5V
Low Vol
tage O peration:2.7V to 3.6V
Shutdow n M ode
4mm × 4mm Q FN Package
Design Fil f this circuit are avail e.
es or
abl
Cal the LTC factory.
l
,LTC and LT are registered trademarks ofLinear Technol Corporation.
ogy
DC1304 QUICK START GUIDE
Q U ICK TEST SETU P – PAR ALLEL CO N TR O L
Q U IC K T E S T P R O C E D U R E
Proce
Test Proce dure
1.
Connect DC1304 as show n,turn on pow er and adj
ust
the R BI
AS1 pot f 50M H z.
or
2.
Connect 50 ohm terminator to AI
N-(J2) and sinew ave
generator to AI + (J1).
N
3.
Connect osciloscope to VO UTA+ and on the oscilo-
l
l
scope displ must show a 1Vp-p sinew ave.
ay
4.
Connect osciloscope to VO UTA- and on the oscilo-
l
l
scope displ must show a 1Vp-p sinew ave.
ay
7.
6.
5.
Connect 50 ohm terminator to BI
N-(J2) and sinew ave
generator to BI + (J1).
N
Connect osciloscope to VO UTB+ and on the oscilo-
l
l
scope displ must show a 1Vp-p sinew ave.
ay
Connect osciloscope to VO UTB- and on the oscilo-
l
l
scope displ must show a 1Vp-p sinew ave.
ay
2
DC1304 QUICK START GUIDE
LTC6602 FCLK AN D FCU TO FF R AN G E
FCLK R ange, 24M H z to 90M H z
LTC6602 FCLK AN D FCU TO FF R AN G E
FCLK R ange, 12M H z to 80M H z
RBI = (4.941 10^9) /FCLK;R BI in k
AS
AS
Exampl I FCLK = 50 M H z Then
e: f
RBI = (4.941 10^9) /(50 10^6) = 98.82k
AS
RBI = (2.472 10^9) /FCLK;R BI in k
AS
AS
Exampl I FCLK = 50 M H z Then
e: f
RBI = (2.472 10^9) /(50 10^6) = 49.44k
AS
The Low pass FCUTOFF = FCLK /N LP
The H ighpass FCU TO FF = FCLK /NH P
NLP and NH P are the cl dividers set by the
ock
(LPF1,LPF0) and (H PF1,H PF0) inputs respectivel
y.
LPF1 LPF0 NLP
0
0
1
1
0
1
0
1
600
300
100
100
HPF1 HPF0 NHP
0
0
1
1
0
1
0
1
6000
2000
1000
Bypass
HPF
The Low pass FCUTOFF = FCLK /N LP
NLP cl divider set by the (LPF1,LPF0) inputs.
ock
LPF1 LPF0 NLP
0
0
1
1
0
1
0
1
512
128
32
32
Low pass Fil FCU TO FF R ange
ter
NLP
Low pass Fil FCU TO FF R ange
ter
Range
375kH z – 2.5M H z
93.75kH z – 625kH z
23.44kH z – 156.25kH z
32
128
512
NLP
100
300
600
Range
240kH z – 900kH z
80kH z – 300kH z
40kH z – 150kH z
H ighpass Fil FCU TO FF R ange
ter
NHP
Range
1000 24kH z – 90kH z
2000 12kH z – 45kH z
6000 4kH z – 15kH z
3