LTC5508
300MHz to 7GHz RF Power
Detector with Buffered Output
in SC70 Package
FEATURES
s
s
s
s
s
s
s
s
DESCRIPTIO
Temperature Compensated Internal Schottky
Diode RF Detector
Wide Input Frequency Range: 300MHz to 7GHz
Wide Input Power Range: –32dBm to 12dBm
Buffered Detector Output
Wide V
CC
Range of 2.7V to 6V
Low Operating Current: 550µA
Low Shutdown Current: <2µA
SC70 Package
The LTC
®
5508 is an RF power detector for RF applications
operating in the 300MHz to 7GHz range. A temperature
compensated Schottky diode peak detector and buffer
amplifier are combined in a small SC70 package. The
supply voltage range is optimized for operation from a
single lithium-ion cell or 3xNiMH.
The RF input voltage is peak detected using an on-chip
Schottky diode. The detected voltage is buffered and
supplied to the V
OUT
pin. A power saving shutdown mode
reduces supply current to less than 2µA.
The LTC5508 operates with input power levels from
–32dBm to 12dBm.
, LTC and LT are registered trademarks of Linear Technology Corporation.
APPLICATIO S
s
s
s
s
s
s
s
802.11a, 802.11b, 802.11g, 802.15
Multimode Mobile Phone Products
Optical Data Links
Wireless Data Modems
Wireless and Cable Infrastructure
RF Power Alarm
Envelope Detector
TYPICAL APPLICATIO
Output Voltage vs RF Input Power
10000
V
CC
= 3.6V
T
A
= 25°C
RF
INPUT
33pF
6
2
LTC5508
V
CC
4
RF
IN
GND
SHDN
GND
V
OUT
5
3
V
OUT
100pF
V
CC
0.1µF
V
OUT
OUTPUT VOLTAGE (mV)
300MHz to 7GHz RF Power Detector
1000
2GHz
1GHz
4GHz
6GHz
7GHz
DISABLE ENABLE
1
5508 TA01
100
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
U
8 12
5508 TA02
U
U
5508fa
1
LTC5508
ABSOLUTE
(Note 1)
AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
TOP VIEW
SHDN 1
GND 2
V
OUT
3
6 RF
IN
5 GND
4 V
CC
V
CC
, V
OUT
to GND .................................... –0.3V to 6.5V
RF
IN
Voltage ......................................(V
CC
±
1.3V) to 7V
SHDN Voltage to GND ................ –0.3V to (V
CC
+ 0.3V)
I
VOUT
...................................................................... 5mA
Operating Temperature Range (Note 2) .. – 40°C to 85°C
Maximum Junction Temperature ......................... 125°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
LTC5508ESC6
SC6 PART
MARKING
LAAD
SC6 PACKAGE
6-LEAD PLASTIC SC70
T
JMAX
= 125°C,
θ
JA
= 256°C/W
Consult LTC Marketing for parts specified with wider operating temperature ranges.
The
q
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 3.6V, SHDN = V
CC
= HI, SHDN = 0V = LO, RF Input Signal is Off,
unless otherwise noted.
PARAMETER
V
CC
Operating Voltage
I
VCC
Shutdown Current
I
VCC
Operating Current
V
OUT
V
OL
(No RF Input)
V
OUT
Output Current
V
OUT
Enable Time
V
OUT
Bandwidth
V
OUT
Load Capacitance
V
OUT
Slew Rate
V
OUT
Noise
SHDN Voltage, Chip Disabled
SHDN Voltage, Chip Enabled
SHDN Input Current
RF
IN
Input Frequency Range
RF
IN
Input Power Range
RF
IN
AC Input Resistance
RF
IN
Input Shunt Capacitance
RF Frequency = 300MHz to 7GHz (Note 5, 6) V
CC
= 2.7V to 6V
F = 1000MHz, Pin = –25dBm
F = 1000MHz, Pin = –25dBm
SHDN = LO
SHDN = HI, I
VOUT
= 0mA
R
LOAD
= 2k, SHDN = HI, Enabled
SHDN = LOW, Disabled
V
OUT
= 1.75V, V
CC
= 2.7V,
∆V
OUT
= 10mV
SHDN = HI, C
LOAD
= 33pF, R
LOAD
= 2k
C
LOAD
= 33pF, R
LOAD
= 2k (Note 4)
(Note 6)
V
RFIN
= 2V Step, C
LOAD
= 33pF, R
LOAD
= 2k (Note 3)
V
CC
= 3V, Noise BW = 1.5MHz, 50Ω RF Input Termination
V
CC
= 2.7V to 6V
V
CC
= 2.7V to 6V
SHDN = 3.6V
q
q
q
q
q
q
ELECTRICAL CHARACTERISTICS
CONDITIONS
MIN
q
q
q
TYP
MAX
6
2
UNITS
V
µA
mA
mV
mV
mA
µs
MHz
pF
V/µs
mV
P-P
2.7
0.55
150
1
250
1
2
8
2
0.85
400
20
33
5
2
0.35
1.4
24
300 to 7000
–32 to 12
150
0.6
40
Note 1:
Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2:
Specifications over the –40°C to 85°C operating temperature
range are assured by design, characterization and correlation with
statistical process controls.
Note 3:
The rise time at V
OUT
is measured between 0.5V and 1.5V.
Note 4:
Bandwidth is calculated using the 10% to 90% rise time equation:
BW = 0.35/rise time.
Note 5:
RF performance is tested at 1800MHz
Note 6:
Guaranteed by design.
5508fa
2
U
V
V
µA
MHz
dBm
Ω
pF
W
U
U
W W
W
LTC5508
TYPICAL PERFOR A CE CHARACTERISTICS
Typical Detector Characteristics,
300MHz
10000
V
CC
= 3.6V
10000
V
OUT
OUTPUT VOLTAGE (mV)
V
OUT
OUTPUT VOLTAGE (mV)
1000
T
A
= –40°C
T
A
= 85°C
T
A
= 25°C
1000
T
A
= –40°C
T
A
= 25°C
T
A
= 85°C
V
OUT
OUTPUT VOLTAGE (mV)
100
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
Typical Detector Characteristics,
3000MHz
10000
V
CC
= 3.6V
10000
V
OUT
OUTPUT VOLTAGE (mV)
V
OUT
OUTPUT VOLTAGE (mV)
1000
T
A
= –40°C
T
A
= 85°C
1000
T
A
= –40°C
T
A
= 85°C
V
OUT
OUTPUT VOLTAGE (mV)
T
A
= 25°C
100
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
Typical Detector Characteristics,
6000MHz
10000
V
CC
= 3.6V
10000
V
OUT
OUTPUT VOLTAGE (mV)
1000
T
A
= –40°C
T
A
= 85°C
V
OUT
OUTPUT VOLTAGE (mV)
100
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
U W
8 12
5508 G01
5508 G04
Typical Detector Characteristics,
1000MHz
V
CC
= 3.6V
10000
Typical Detector Characteristics,
2000MHz
V
CC
= 3.6V
1000
T
A
= –40°C
T
A
= 85°C
T
A
= 25°C
100
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G02
100
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G03
Typical Detector Characteristics,
4000MHz
V
CC
= 3.6V
10000
Typical Detector Characteristics,
5000MHz
V
CC
= 3.6V
1000
T
A
= –40°C
T
A
= 85°C
T
A
= 25°C
100
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
T
A
= 25°C
8 12
8 12
5508 G05
100
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G06
Typical Detector Characteristics,
7000MHz
V
CC
= 3.6V
1000
T
A
= –40°C
T
A
= 85°C
T
A
= 25°C
100
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
T
A
= 25°C
8 12
5508 G07
8 12
5508 G08
5508fa
3
LTC5508
TYPICAL PERFOR A CE CHARACTERISTICS
V
OUT
Slope vs RF Input Power at
300MHz
1000
V
CC
= 3.6V
V
OUT
SLOPE (mV/dB)
V
OUT
SLOPE (mV/dB)
100
100
V
OUT
SLOPE (mV/dB)
10 T
A
= –40°C
T
A
= 25°C
T
A
= 85°C
1
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G09
V
OUT
Slope vs RF Input Power at
3000MHz
1000
V
CC
= 3.6V
1000
V
OUT
SLOPE (mV/dB)
V
OUT
SLOPE (mV/dB)
100
100
V
OUT
SLOPE (mV/dB)
T
A
= –40°C
10
T
A
= 25°C
T
A
= 85°C
1
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G12
V
OUT
Slope vs RF Input Power at
6000MHz
1000
V
CC
= 3.6V
V
OUT
SLOPE (mV/dB)
V
OUT
SLOPE (mV/dB)
100
10
T
A
= –40°C
T
A
= 25°C
T
A
= 85°C
1
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
4
U W
V
OUT
Slope vs RF Input Power at
1000MHz
1000
V
CC
= 3.6V
1000
V
OUT
Slope vs RF Input Power at
2000MHz
V
CC
= 3.6V
100
10
T
A
= –40°C
T
A
= 25°C
T
A
= 85°C
10
T
A
= –40°C
T
A
= 25°C
T
A
= 85°C
1
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G10
1
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G11
V
OUT
Slope vs RF Input Power at
4000MHz
V
CC
= 3.6V
1000
V
OUT
Slope vs RF Input Power at
5000MHz
V
CC
= 3.6V
100
10
T
A
= –40°C
T
A
= 25°C
T
A
= 85°C
10
T
A
= –40°C
T
A
= 25°C
T
A
= 85°C
1
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G13
1
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G14
V
OUT
Slope vs RF Input Power at
7000MHz
1000
V
CC
= 3.6V
100
10
T
A
= –40°C
T
A
= 25°C
T
A
= 85°C
8 12
5508 G15
1
–32 –28 –24 –20 –16 –12 –8 –4 0 4
RF INPUT POWER (dBm)
8 12
5508 G16
5508fa
LTC5508
TYPICAL PERFOR A CE CHARACTERISTICS
RF
IN
Input Impedance (Pin = 0dBm, V
CC
= 3.6V, T
A
= 25°C)
FREQUENCY
(GHz)
1.000
1.375
1.750
2.125
2.500
2.875
3.250
3.625
4.000
4.375
4.750
5.125
5.500
5.875
6.250
6.625
7.000
RESISTANCE
(Ω)
129.136
100.771
73.844
60.159
50.135
43.042
37.570
33.924
30.923
28.793
26.992
25.717
24.920
24.318
24.549
25.273
26.337
REACTANCE
(Ω)
–86.960
–92.142
–81.141
–68.796
–58.139
–48.927
–41.033
–33.346
–26.405
–20.012
–14.080
–8.323
–3.228
2.177
7.535
12.197
16.503
RF
IN
Input Impedance (Pin = –25dBm, V
CC
= 3.6V, T
A
= 25°C)
FREQUENCY
(GHz)
1.000
1.375
1.750
2.125
2.500
2.875
3.250
3.625
4.000
4.375
4.750
5.125
5.500
5.875
6.250
6.625
7.000
RESISTANCE
(Ω)
114.531
95.061
71.491
59.563
51.714
44.940
39.708
36.151
33.227
31.108
29.514
27.899
27.047
26.627
26.760
27.619
28.241
REACTANCE
(Ω)
–63.267
–71.669
–64.607
–54.798
–46.844
–39.753
–32.738
–26.385
–20.478
–15.107
–9.941
–4.793
0.266
5.250
10.267
14.616
18.523
U W
S11 Forward Reflection
Impedance
1.000GHz-7.000GHz
5508 TA03
S11 Forward Reflection
Impedance
1.000GHz-7.000GHz
5508 TA04
5508fa
5