PA ANTENNA
RFIN/ENOUT
LMV226/
LMV228
RF
ENABLE
R2
10 k:
VDD
GND
50:
C
100 pF
PA ANTENNA
OUT
RF
VDD
GND
RFIN/ENLMV225
R1
1.8 k:
R2
10 k:
ENABLE
C
100 pF
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
LMV225/LMV226/LMV228 RF Power Detector for CDMA and WCDMA
Check for Samples: LMV225,LMV226,LMV228
1FEATURES DESCRIPTION
The LMV225/LMV226/LMV228 are 30 dB RF power
2• 30 dB Linear in dB Power Detection Range detectors intended for use in CDMA and WCDMA
• Output Voltage Range 0.2 to 2V applications. The device has an RF frequency range
• Logic Low Shutdown from 450 MHz to 2 GHz. It provides an accurate
temperature and supply compensated output voltage
• Multi-Band Operation from 450 MHz to 2000 that relates linearly to the RF input power in dBm.
MHz The circuit operates with a single supply from 2.7V to
• Accurate Temperature Compensation 5.5V. The LMV225/LMV226/LMV228 have an
• Packages: integrated filter for low-ripple average power detection
of CDMA signals with 30 dB dynamic range.
– DSBGA Thin 1.0 mm x 1.0 mm x 0.6 mm Additional filtering can be applied using a single
– DSBGA Ultra Thin 1.0 mm x 1.0 mm x 0.35 external capacitor.
mm The LMV225 has an RF power detection range from
– WSON 2.2 mm x 2.5 mm x 0.8 mm –30 dBm to 0 dBm and is ideally suited for direct use
– (LMV225 and LMV228) in combination with resistive taps. The
LMV226/LMV228 have a detection range from –15
APPLICATIONS dBm to 15 dBm and are intended for use in
combination with a directional coupler. The LMV226
• CDMA RF Power Control is equipped with a buffered output which makes it
• WCDMA RF Power Control suitable for GSM, EDGE, GPRS and TDMA
• CDMA2000 RF Power Control applications.
• PA Modules The device is active for Enable = HI, otherwise it is in
a low power consumption shutdown mode. During
shutdown the output will be LOW. The output voltage
ranges from 0.2V to 2V and can be scaled down to
meet ADC input range requirements.
The LMV225/LMV226/LMV228 power detectors are
offered in the thin 1.0 mm x 1.0 mm x 0.6 mm
DSBGA package and the ultra thin 1.0 mm x 1.0 mm
x 0.35 mm DSBGA package. The LMV225 and the
LMV228 are also offered in the 2.2 mm x 2.5 mm x
0.8 mm WSON package.
Typical Application
Figure 1. LMV225 Figure 2. LMV226/LMV228
1Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2003–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
ABSOLUTE MAXIMUM RATINGS (1)(2)
Supply Voltage
VDD - GND 6.0V Max
ESD Tolerance (3)
Human Body Model 2000V
Machine Model 200V
Storage Temperature Range −65°C to 150°C
Junction Temperature (4) 150°C Max
Mounting Temperature, Infrared or convection (20 sec)
Tin/Lead 235°C
Lead-Free 260°C
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but specific performance is not specified. For specifications and the test conditions, see
the Electrical Characteristics.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
(3) Human body model: 1.5 kΩin series with 100 pF. Machine model, 0Ωin series with 100 pF.
(4) The maximum power dissipation is a function of TJ(MAX) ,θJA and TA. The maximum allowable power dissipation at any ambient
temperature is PD= (TJ(MAX) - TA)/θJA. All numbers apply for packages soldered directly into a PC board
OPERATING RATINGS (1)
Supply Voltage 2.7V to 5.5V
Temperature Range −40°C to +85°C
RF Frequency Range 450 MHz to 2 GHz
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but specific performance is not specified. For specifications and the test conditions, see
the Electrical Characteristics.
2Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
2.7 DC AND AC ELECTRICAL CHARACTERISTICS
Unless otherwise specified, all limits are specified to VDD = 2.7V; TJ= 25°C. Boldface limits apply at temperature extremes. (1)
Symbol Parameter Condition Min Typ Max Units
IDD Supply Current Active Mode: RFIN/EN= VDD LMV225 4.8 7
(DC), No RF Input Power 8
Present LMV226 4.9 6.2 mA
8
LMV228 4.9 6.2
8
Shutdown: RFIN/EN= GND (DC), No RF Input 0.44 4.5 μA
Power Present
VLOW ENLogic Low Input Level 0.8 V
(2)
VHIGH ENLogic High Input Level 1.8 V
(2)
ton Turn-on-Time (3) No RF Input Power Present, LMV225 2.1
Output Loaded with 10 pF LMV226 1.2 μs
LMV228 1.7
trRise Time (4) Step from no Power to LMV225 4.5
0 dBm Applied, Output
Loaded with 10 pF μs
Step from no Power to LMV226 1.8
15 dBm Applied, Output LMV228 4.8
Loaded with 10 pF
IEN Current into RFIN/ENPin 1μA
PIN Input Power Range (5) LMV225 −30 dBm
0
−43 dBV
−13
LMV226 −15 dBm
15
−28 dBV
2
LMV228 −15 dBm
15
−28 dBV
2
(1) Electrical Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device such that TJ= TA. No specification of parametric performance is indicated in the electrical tables under
conditions of internal self-heating where TJ> TA.
(2) All limits are specified by design or statistical analysis
(3) Turn-on time is measured by connecting a 10 kΩresistor to the RFIN/ENpin. Be aware that in the actual application on the front page,
the RC-time constant of resistor R2and capacitor C adds an additional delay.
(4) Typical values represent the most likely parametric norm.
(5) Power in dBV = dBm + 13 when the impedance is 50Ω.
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 3
Product Folder Links: LMV225 LMV226 LMV228
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
2.7 DC AND AC ELECTRICAL CHARACTERISTICS (continued)
Unless otherwise specified, all limits are specified to VDD = 2.7V; TJ= 25°C. Boldface limits apply at temperature extremes. (1)
Symbol Parameter Condition Min Typ Max Units
Logarithmic Slope (6) 900 MHz LMV225 44.0
LMV226 44.5
LMV228 44.0
DSBGA
LMV228 WSON 48.5
1800 MHz LMV225 39.4
LMV226 41.6
LMV228 41.9
DSBGA
LMV228 WSON 47.4 mV/dB
1900 MHz LMV225 38.5
LMV226 41.2
LMV228 41.6
DSBGA
LMV228 WSON 46.6
2000 MHz LMV225 38.5
LMV226 41.0
LMV228 41.2
DSBGA
LMV228 WSON 45.4
Logarithmic Intercept (6) 900 MHz LMV225 −45.5
LMV226 −24.5
LMV228 −27.2
DSBGA
LMV228 WSON −23.7
1800 MHz LMV225 −46.6
LMV226 −25.1
LMV228 −28.2
DSBGA
LMV228 WSON −23.8 dBm
1900 MHz LMV225 −46.3
LMV226 −24.9
LMV228 −28.0
DSBGA
LMV228 WSON −23.7
2000 MHz LMV225 −46.7
LMV226 −24.7
LMV228 −28.0
DSBGA
LMV228 WSON -23.6
VOUT Output Voltage No RF Input Power Present LMV225 214 350
LMV226 223 350 mV
LMV228 228 350
IOUT Output Current Sourcing/Sinking LMV226 Only 4.5 5.3 mA
ROUT Output Impedance LMV225/LMV228 only, no RF Input Power 19.8 29 kΩ
Present 34
(6) Device is set in active mode with a 10 kΩresistor from VDD to RFIN/EN. RF signal is applied using a 50ΩRF signal generator AC
coupled to the RFIN/ENpin using a 100 pF coupling capacitor.
4Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
2.7 DC AND AC ELECTRICAL CHARACTERISTICS (continued)
Unless otherwise specified, all limits are specified to VDD = 2.7V; TJ= 25°C. Boldface limits apply at temperature extremes. (1)
Symbol Parameter Condition Min Typ Max Units
enOutput Referred Noise RF Input = 1800 MHz, −10 dBm for LMV225 700
and 5 dBm for LMV226/LMV228, Measured at nV/√Hz
10 kHz
Variation Due to Temperature 900 MHz, RFIN = 0 dBm LMV225 +0.64
Referred to 25°C −1.07
900 MHz, RFIN = 15 dBm LMV226 +0.05
Referred to 25°C −0.02
LMV228 +0.22
DSBGA −0.36
LMV228 WSON +0.87
−0.87
1800 MHz, RFIN = 0 dBm LMV225 +0.09
Referred to 25°C −0.86
1800 MHz, RFIN = 15 dBm LMV226 +0.07
Referred to 25°C −0.10
LMV228 +0.29
DSBGA −0.57
LMV228 WSON +1.04
−1.23 dB
1900 MHz, RFIN = 0 dBm LMV225 +0
Referred to 25°C −0.69
1900 MHz, RFIN = 15 dBm LMV226 +0
Referred to 25°C −0.10
LMV228 +0.23
DSBGA −0.64
LMV228 WSON +1.05
−1.45
2000 MHz, RFIN = 0 dBm LMV225 +0
Referred to 25°C −0.86
2000 MHz, RFIN = 15 dBm LMV226 +0
Referred to 25°C −0.29
LMV228 +0.27
DSBGA −0.65
LMV228 WSON +1.04
−2.02
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 5
Product Folder Links: LMV225 LMV226 LMV228
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
5.0 DC AND AC ELECTRICAL CHARACTERISTICS
Unless otherwise specified, all limits are specified to VDD = 5.0V; TJ= 25°C. Boldface limits apply at temperature extremes. (1)
Symbol Parameter Condition Min Typ Max Units
IDD Supply Current Active Mode: RFIN/EN= VDD LMV225 5.3 7.5
(DC), no RF Input Power 9
Present. LMV226 5.3 6.8 mA
9
LMV228 5.4 6.8
9
Shutdown: RFIN/EN= GND (DC), no RF Input 0.32 4.5 μA
Power Present.
VLOW ENLogic Low Input Level 0.8 V
(2)
VHIGH ENLogic High Input Level 1.8 V
(2)
ton Turn-on-Time (3) No RF Input Power Present, LMV225 2.1
Output Loaded with 10 pF LMV226 1.0 μs
LMV228 1.7
trRise Time (4) Step from no Power to LMV225 4.5
0 dBm Applied, Output
Loaded with 10 pF μs
Step from no Power to LMV226 1.4
15 dBm Applied, Output LMV228 4.8
Loaded with 10 pF
IEN Current Into RFIN/ENPin 1μA
PIN Input Power Range (5) LMV225 −30 dBm
0
−43 dBV
−13
LMV226 −15 dBm
15
−28 dBV
2
LMV228 −15 dBm
15
−28 dBV
2
(1) Electrical Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device such that TJ= TA. No specification of parametric performance is indicated in the electrical tables under
conditions of internal self-heating where TJ> TA.
(2) All limits are specified by design or statistical analysis
(3) Turn-on time is measured by connecting a 10 kΩresistor to the RFIN/ENpin. Be aware that in the actual application on the front page,
the RC-time constant of resistor R2and capacitor C adds an additional delay.
(4) Typical values represent the most likely parametric norm.
(5) Power in dBV = dBm + 13 when the impedance is 50Ω.
6Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
5.0 DC AND AC ELECTRICAL CHARACTERISTICS (continued)
Unless otherwise specified, all limits are specified to VDD = 5.0V; TJ= 25°C. Boldface limits apply at temperature extremes. (1)
Symbol Parameter Condition Min Typ Max Units
Logarithmic Slope (6) 900 MHz LMV225 44.6
LMV226 44.6
LMV228 44.2
DSBGA
LMV228 WSON 48.4
1800 MHz LMV225 40.6
LMV226 42.2
LMV228 42.4
DSBGA
LMV228 WSON 48.3 mV/dB
1900 MHz LMV225 39.6
LMV226 41.8
LMV228 42.2
DSBGA
LMV228 WSON 47.8
2000 MHz LMV225 39.7
LMV226 41.6
LMV228 41.8
DSBGA
LMV228 WSON 47.2
Logarithmic Intercept (6) 900 MHz LMV225 −47.0
LMV226 −25.0
LMV228 −27.7
DSBGA
LMV228 WSON −23.9
1800 MHz LMV225 −48.5
LMV226 −25.7
LMV228 −28.9
DSBGA
LMV228 WSON −23.6 dBm
1900 MHz LMV225 −48.2
LMV226 −25.6
LMV228 −28.7
DSBGA
LMV228 WSON −23.1
2000 MHz LMV225 −48.9
LMV226 −25.5
LMV228 −28.7
DSBGA
LMV228 WSON −23.0
VOUT Output Voltage No RF Input Power Present LMV225 222 400
LMV226 231 400 mV
LMV228 244 400
IOUT Output Current Sourcing/Sinking LMV226 Only 4.5 5.3 mA
ROUT Output Impedance No RF Input Power Present 23.7 29 kΩ
31
(6) Device is set in active mode with a 10 kΩresistor from VDD to RFIN/EN. RF signal is applied using a 50ΩRF signal generator AC
coupled to the RFIN/ENpin using a 100 pF coupling capacitor.
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 7
Product Folder Links: LMV225 LMV226 LMV228
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
5.0 DC AND AC ELECTRICAL CHARACTERISTICS (continued)
Unless otherwise specified, all limits are specified to VDD = 5.0V; TJ= 25°C. Boldface limits apply at temperature extremes. (1)
Symbol Parameter Condition Min Typ Max Units
enOutput Referred Noise RF Input = 1800 MHz, −10 dBm for LMV225 700 nV/√Hz
and 5 dBm for LMV226/LMV228, Measured at
10 kHz
Variation Due to Temperature 900 MHz, RFIN = 0 dBm LMV225 +0.89
Referred to 25°C −1.16
900 MHz, RFIN = 15 dBm LMV226 +0.25
Referred to 25°C −0.16
LMV228 +0.46
DSBGA −0.62
LMV228 WSON +1.39
−1.19
1800 MHz, RFIN = 0 dBm LMV225 +0.3
Referred to 25°C −0.82
1800 MHz, RFIN = 15 dBm LMV226 +0.21
Referred to 25°C −0.09
LMV228 +0.55
DSBGA −0.78
LMV228 WSON +1.39
−1.43 dB
1900 MHz, RFIN = 0 dBm LMV225 +0.34
Referred to 25°C −0.63
1900 MHz, RFIN = 15 dBm LMV226 +0.21
Referred to 25°C −0.19
LMV228 +0.55
DSBGA −0.93
LMV228 WSON +1.54
−1.64
2000 MHz, RFIN = 0 dBm LMV225 +0.22
Referred to 25°C −0.75
2000 MHz RFIN = 15 dBm LMV226 +0.25
Referred to 25°C −0.34
LMV228 +0.61−
DSBGA 0.91
LMV228 WSON +0.89
−0.99
8Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
A2
RFIN/ENA1
GND B2
VDD
B1 OUT
1.0mm
1.0mm
BUMP PITCH
BUMP DIAMETER
SOLDER DOT DIAMETER/
PASSIVATION OPENING
500Pm
300Pm
125Pm
6
5
4
OUT
NC
VDD
GND
NC
RFIN/EN
1
2
3
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
CONNECTION DIAGRAM
Figure 3. 4-Bump DSBGA – Top View Figure 4. 6-pin WSON – Top View
See Package Number YZR0004 or YPD0004 See Package Number NGF0006A
PIN DESCRIPTIONS
Pin Name Description
DSBGA WSON6
Power Supply A2 4 VDD Positive Supply Voltage
B1 1 GND Power Ground
A1 3 RFIN/ENDC voltage determines enable state of the device (HIGH =
device active). AC voltage is the RF input signal to the
detector (beyond 450 MHz). The RFIN/ENpin is internally
terminated with 50Ωin series with 45 pF.
Output B2 6 Out Ground referenced detector output voltage (linear in dBm)
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 9
Product Folder Links: LMV225 LMV226 LMV228
GND
OUT
10 dB 10 dB
RFIN/EN10 dB
LOGIC ENABLE
VDD
I / I +
-
OUT
10 dB
DETECTOR
10 dB
RFIN/EN10 dB
LOGIC ENABLE
VDD
GND
I / I
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
Block Diagrams
Figure 5. LMV225
Figure 6. LMV226
10 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
OUT
10 dB 10 dB
RFIN/EN10 dB
LOGIC ENABLE
VDD
GND
I / I
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
Figure 7. LMV228
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 11
Product Folder Links: LMV225 LMV226 LMV228
-50 -40 -30 -20 -10 0 10 20
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
VOUT (V)
RF INPUT POWER (dBm)
-40°C
25°C
85°C
85°C
25°C
-40°C
-5
-4
-3
-2
-1
0
1
2
3
4
5
ERROR (dB)
-50 -40 -30 -20 -10 0 10 20
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
VOUT (V)
RF INPUT POWER (dBm)
-40°C
25°C
85°C
85°C
25°C
-40°C
-5
-4
-3
-2
-1
0
1
2
3
4
5
ERROR (dB)
-50 -40 -30 -20 -10 0 10 20
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
VOUT (V)
RF INPUT POWER (dBm)
-40°C
25°C
85°C
85°C
25°C
-40°C
-5
-4
-3
-2
-1
0
1
2
3
4
5
ERROR (dB)
2.5 3 3.5 4 4.5 5
4
4.5
5
5.5
6
6.5
7
7.5
8
SUPPLY CURRENT (mA)
SUPPLY VOLTAGE (V)
85°C
25°C
-40°C
-50 -40 -30 -20 -10 0 10 20
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
VOUT (V)
RF INPUT POWER (dBm)
900MHz
1800MHz
1900MHz
2000MHz
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS LMV225
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Supply Current Output Voltage
vs. vs.
Supply Voltage (LMV225) RF Input Power (LMV225)
Figure 8. Figure 9.
Output Voltage and Log Conformance vs. Output Voltage and Log Conformance vs.
RF Input Power @ 900 MHz (LMV225) RF Input Power @ 1800 MHz (LMV225)
Figure 10. Figure 11.
Output Voltage and Log Conformance
vs. Output Voltage and Log Conformance vs.
RF Input Power @ 1900 MHz (LMV225) RF Input Power @ 2000 MHz (LMV225)
Figure 12. Figure 13.
12 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
20
ERROR (dB)
85°C
-40°C
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
20
ERROR (dB)
85°C
-40°C
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
20
ERROR (dB)
85°C
-40°C
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
20
ERROR (dB)
85°C
-40°C
400 800 1200 1600 2000
37
47
SLOPE (mV/dB)
FREQUENCY (MHz)
38
39
40
41
42
43
44
45
46 -40°C
25°C
85°C
400 800 1200 1600 2000
FREQUENCY (MHz)
-48
-47
-46
-45
-44
-43
INTERCEPT (dBm)
-40°C
25°C
85°C
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
TYPICAL PERFORMANCE CHARACTERISTICS LMV225
(continued)
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Logarithmic Slope vs. Frequency (LMV225) Logarithmic Intercept vs. Frequency (LMV225)
Figure 14. Figure 15.
Output Variation vs. RF Input Power Output Variation vs. RF Input Power
Normalized to 25°C @ 900 MHz (LMV225) Normalized to 25°C @ 1800 MHz (LMV225)
Figure 16. Figure 17.
Output Variation vs. RF Input Power Output Variation vs. RF Input Power
Normalized to 25°C @ 1900 MHz (LMV225) Normalized to 25°C @ 2000 MHz (LMV225)
Figure 18. Figure 19.
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 13
Product Folder Links: LMV225 LMV226 LMV228
2.5 33.5 44.5 5
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
SUPPLY CURRENT (mA)
SUPPLY VOLTAGE (V)
85°C
25°C
-40°C
-50 -40 -30 -20 -10 010 20
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
VOUT (V)
RF INPUT POWER (dBm)
900 MHz
1800 MHz
1900 MHz
2000 MHz
0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
FREQUENCY (GHz)
-100
-50
0
50
100
150
IMPEDANCE (:)
R
X
100 1k 10k 100k 1M
FREQUENCY (Hz)
0
10
20
30
40
50
60
70
PSRR (dB)
2.7V
5V
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS LMV225
(continued)
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
PSRR vs.Frequency PSRR vs. Frequency
(LMV225 in DSBGA) (LMV225 in WSON)
Figure 20. Figure 21.
RF Input Impedance vs. Frequency @ Resistance and RF Input Impedance vs. Frequency @ Resistance and
Reactance (LMV225 in DSBGA) Reactance (LMV225 in WSON)
Figure 22. Figure 23.
TYPICAL PERFORMANCE CHARACTERISTICS LMV226
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Supply Current vs. Supply Voltage (LMV226) Output Voltage vs. RF Input Power (LMV226)
Figure 24. Figure 25.
14 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
400 800 1200 1600 2000
FREQUENCY (MHz)
39
40
41
42
43
44
45
46
SLOPE (mV/dB)
-40°C
85°C
25°C
400 800 1200 1600 2000
FREQUENCY (MHz)
-26.5
-26.0
-25.5
-25.0
-24.5
-24.0
-23.5
-23.0
INTERCEPT (dBm)
-40°C
25°C
85°C
-50 -40 -30 -20 -10 0 10 20
2.00
VOUT (V)
RF INPUT POWER (dBm)
-5
-4
-3
-2
-1
0
1
2
4
5
3
2.50
2.25
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ERROR (dB)
25°C
-40°C
85°C
25°C
-40°C
85°C
-50 -40 -30 -20 -10 010 20
2.00
VOUT (V)
RF INPUT POWER (dBm)
-5
-4
-3
-2
-1
0
1
2
4
5
3
2.50
2.25
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ERROR (dB)
25°C
-40°C
85°C
25°C
-40°C
85°C
-50 -40 -30 -20 -10 010 20
2.00
VOUT (V)
RF INPUT POWER (dBm)
-5
-4
-3
-2
-1
0
1
2
4
5
3
2.50
2.25
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ERROR (dB)
25°C
-40°C
85°C
25°C
-40°C
85°C
-50 -40 -30 -20 -10 010 20
2.00
VOUT (V)
RF INPUT POWER (dBm)
-5
-4
-3
-2
-1
0
1
2
4
5
3
2.50
2.25
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ERROR (dB)
25°C
-40°C
85°C
25°C
-40°C
85°C
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
TYPICAL PERFORMANCE CHARACTERISTICS LMV226
(continued)
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Output Voltage and Log Conformance vs. Output Voltage and Log Conformance vs. RF Input Power
RF Input Power @ 900 MHz (LMV226) @ 1800 MHz (LMV226)
Figure 26. Figure 27.
Output Voltage and Log Conformance vs. RF Input Power Output Voltage and Log Conformance vs. RF Input Power
@ 1900 MHz (LMV226) @ 2000 MHz (LMV226)
Figure 28. Figure 29.
Logarithmic Slope vs. Frequency (LMV226) Logarithmic Intercept vs. Frequency (LMV226)
Figure 30. Figure 31.
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 15
Product Folder Links: LMV225 LMV226 LMV228
100 1k 10k 100k 1M
FREQUENCY (Hz)
0
10
20
30
40
50
60
70
PSRR (dB)
2.7V
5V
0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
FREQUENCY (GHz)
-100
-50
0
50
100
150
IMPEDANCE (:)
R
X
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
ERROR (dB)
20
-40°C
85°C
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
20
ERROR (dB)
85°C
-40°C
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
ERROR (dB)
20
-40°C
85°C
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
ERROR (dB)
20
85°C
-40°C
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS LMV226
(continued)
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Output Variation vs. RF Input Power Output Variation vs. RF Input Power
Normalized to 25°C @ 900 MHz (LMV226) Normalized to 25°C @ 1800 MHz (LMV226)
Figure 32. Figure 33.
Output Variation vs. RF Input Power Output Variation vs. RF Input Power
Normalized to 25°C @ 1900 MHz (LMV226) Normalized to 25°C @ 2000 MHz (LMV226)
Figure 34. Figure 35.
PSRR vs. Frequency RF Input Impedance vs. Frequency @ Resistance and
(LMV226) Reactance (LMV226)
Figure 36. Figure 37.
16 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
-50 -40 -30 -20 -10 0 10 20
2.00
VOUT (V)
RF INPUT POWER (dBm)
-5
-4
-3
-2
-1
0
1
2
4
5
3
2.50
2.25
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ERROR (dB)
25°C
-40°C
85°C
25°C
-40°C
85°C
-50 -40 -30 -20 -10 0 10 20
2.00
VOUT (V)
RF INPUT POWER (dBm)
-5
-4
-3
-2
-1
0
1
2
4
5
3
2.50
2.25
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ERROR (dB)
25°C
-40°C
85°C
25°C
-40°C
85°C
-50 -40 -30 -20 -10 0 10 20
2.00
VOUT (V)
RF INPUT POWER (dBm)
-5
-4
-3
-2
-1
0
1
2
4
5
3
2.50
2.25
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ERROR (dB)
25°C
-40°C
85°C
25°C
-40°C
85°C
-50 -40 -30 -20 -10 0 10 20
2.00
VOUT (V)
RF INPUT POWER (dBm)
-5
-4
-3
-2
-1
0
1
2
4
5
3
2.50
2.25
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00
ERROR (dB)
25°C
-40°C
85°C
25°C
-40°C
85°C
-50 -40 -30 -20 -10 0 10 20
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
VOUT (V)
RF INPUT POWER (dBm)
900 MHz
1800 MHz
1900 MHz
2000 MHz
2.5 3 3.5 4 4.5 5
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
SUPPLY CURRENT (mA)
SUPPLY VOLTAGE (V)
85°C
25°C
-40°C
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
TYPICAL PERFORMANCE CHARACTERISTICS LMV228 IN DSBGA
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Supply Current vs. Supply Voltage Output Voltage vs. RF Input Power
(LMV228 in DSBGA) (LMV228 in DSBGA)
Figure 38. Figure 39.
Output Voltage and Log Conformance vs. Output Voltage and Log Conformance vs.
RF Input Power @ 900 MHz (LMV228 in DSBGA) RF Input Power @ 1800 MHz (LMV228 in DSBGA)
Figure 40. Figure 41.
Output Voltage and Log Conformance vs. Output Voltage and Log Conformance vs.
RF Input Power @ 1900 MHz (LMV228 in DSBGA) RF Input Power @ 2000 MHz (LMV228 in DSBGA)
Figure 42. Figure 43.
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 17
Product Folder Links: LMV225 LMV226 LMV228
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
ERROR (dB)
20
-40°C
85°C
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
ERROR (dB)
20
-40°C
85°C
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
ERROR (dB)
20
-40°C
85°C
-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
ERROR (dB)
20
-40°C
85°C
400 800 1200 1600 2000
FREQUENCY (MHz)
-29.0
-28.5
-28.0
-27.5
-27.0
-26.5
-26.0
-25.5
INTERCEPT (dBm)
-40°C
25°C
85°C
400 800 1200 1600 2000
FREQUENCY (MHz)
40.5
41.0
41.5
42.0
42.5
43.0
43.5
44.0
44.5
SLOPE (mV/dB)
-40°C 25°C
85°C
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS LMV228 IN DSBGA
(continued)
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Logarithmic Slope vs. Logarithmic Intercept vs.
Frequency (LMV228 in DSBGA) Frequency (LMV228 in DSBGA)
Figure 44. Figure 45.
Output Variation vs. Output Variation vs.
RF Input Power Normalized to 25°C @ 900 MHz (LMV228 in RF Input Power Normalized to 25°C @ 1800 MHz (LMV228 in
DSBGA) DSBGA)
Figure 46. Figure 47.
Output Variation vs. Output Variation vs.
RF Input Power Normalized to 25°C @ 1900 MHz (LMV228 in RF Input Power Normalized to 25°C @ 2000 MHz (LMV228 in
DSBGA) DSBGA)
Figure 48. Figure 49.
18 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
ERROR (dB)
RF INPUT POWER (dBm)
VOUT (V)
-50 -40 -30 -20 -10 0 10 20
2.00
1.80
1.60
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
5
4
3
2
1
0
-1
-2
-3
-4
-5
25°C
85°C
-40°C
85°C
25°C
-40°C
ERROR (dB)
RF INPUT POWER (dBm)
VOUT (V)
-50 -40 -30 -20 -10 0 10 20
2.00
1.80
1.60
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
5
4
3
2
1
0
-1
-2
-3
-4
-5
25°C
85°C
-40°C
85°C
25°C
-40°C
2.5 3 3.5 4 4.5 5
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
SUPPLY CURRENT (mA)
SUPPLY VOLTAGE (V)
85°C
25°C
-40°C
100 1k 10k 100k 1M
FREQUENCY (Hz)
0
10
20
30
40
50
60
70
PSRR (dB)
2.7V
5V
0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
FREQUENCY (GHz)
-100
-50
0
50
100
150
IMPEDANCE (:)
R
X
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
TYPICAL PERFORMANCE CHARACTERISTICS LMV228 IN DSBGA
(continued)
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
PSRR vs. Frequency RF Input Impedance vs. Frequency @ Resistance and
(LMV228 in DSBGA) Reactance (LMV228 in DSBGA)
Figure 50. Figure 51.
TYPICAL PERFORMANCE CHARACTERISTICS LMV228 IN WSON
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Supply Current Output Voltage
vs. vs.
Supply Voltage (LMV228 in WSON) RF Input Power (LMV228 in WSON)
Figure 52. Figure 53.
Output Voltage and Log Conformance
vs. Output Voltage and Log Conformance vs.
RF Input Power @ 900 MHz (LMV228 inWSON) RF Input Power @ 1800 MHz (LMV228 in WSON)
Figure 54. Figure 55.
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 19
Product Folder Links: LMV225 LMV226 LMV228
ERROR (dB)
RF INPUT POWER (dBm)
VOUT (V)
-50 -40 -30 -20 -10 0 10 20
2.00
1.80
1.60
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
5
4
3
2
1
0
-1
-2
-3
-4
-5
25°C
85°C
-40°C
85°C
25°C
-40°C
ERROR (dB)
RF INPUT POWER (dBm)
VOUT (V)
-50 -40 -30 -20 -10 0 10 20
2.00
1.80
1.60
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
5
4
3
2
1
0
-1
-2
-3
-4
-5
25°C
85°C
-40°C
85°C
25°C
-40°C
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS LMV228 IN WSON
(continued)
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Output Voltage and Log Conformance
vs. Output Voltage and Log Conformance vs.
RF Input Power @ 1900 MHz (LMV228 in WSON) RF Input Power @ 2000 MHz (LMV228 in WSON)
Figure 56. Figure 57.
Logarithmic Slope Logarithmic Intercept
vs. vs.
Frequency (LMV228 in WSON) Frequency (LMV228 in WSON)
Figure 58. Figure 59.
Output Variation Output Variation
vs. vs.
RF Input Power Normalized to 25°C @ 900 MHz (LMV228 in RF Input Power Normalized to 25°C @ 1800 MHz (LMV228 in
WSON) WSON)
Figure 60. Figure 61.
20 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
TYPICAL PERFORMANCE CHARACTERISTICS LMV228 IN WSON
(continued)
Unless otherwise specified, VDD = 2.7V, TJ= 25°C.
Output Variation Output Variation
vs. vs.
RF Input Power Normalized to 25°C @ 1900 MHz (LMV228 in RF Input Power Normalized to 25°C @ 2000 MHz (LMV228 in
WSON) WSON)
Figure 62. Figure 63.
PSRR
vs. RF Input Impedance
Frequency vs.
(LMV228 in WSON) Frequency @ Resistance and Reactance (LMV228 in WSON)
Figure 64. Figure 65.
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 21
Product Folder Links: LMV225 LMV226 LMV228
R1 = -1
10
AdB
20 · RIN = -1
10
31
20 · 50 = 1724:
AdB = 20·LOG R1
RIN
+
1 = 31dB
PA ANTENNA
OUT
RF
VDD
GND
LMV225
R2
10 k:
ENABLE
RFIN/EN
RIN
CIN
100 pF
C
R1
1.8 k:
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
APPLICATION NOTES
CONFIGURING A TYPICAL APPLICATION
The LMV225/LMV226/LMV228 are power detectors intended for CDMA and WCDMA applications. Power
applied at its input translates to a DC voltage on the output through a linear-in-dB response. The LMV225
detector is especially suited for power measurements via a high-resistive tap, while the LMV226/LMV228 are
designed to be used in combination with a directional coupler. The LMV226 has an additional output voltage
buffer and therefore a low output impedance. The key features of the devices are shown in .
Table 1. DEVICE CHARACTERISTICS
Input Range (dBm) Output Buffer Application
LMV225 −30 / 0 No High Resistive Tap
LMV226 −15 / 15 Yes Directional Coupler
LMV228 −15 / 15 No Directional Coupler
In order to match the output power range of the power amplifier (PA) with the range of the LMV225’s input, the
high resistive tap needs to be configured correctly. In case of the LMV226/LMV228 the coupling factor of the
directional coupler needs to be chosen correctly.
HIGH RESISTIVE TAP APPLICATION
The constant input impedance of the device enables the realization of a frequency independent input attenuation
to adjust the LMV225’s range to the range of the PA. Resistor R1and the 50Ωinput resistance (RIN) of the
device realize this attenuation (Figure 66). To minimize insertion loss, resistor R1needs to be sufficiently large.
The following example demonstrates how to determine the proper value for R1.
Figure 66. Typical LMV225 Application with High Resistive Tap
Suppose the useful output power of the PA ranges up to +31 dBm. As the LMV225 can handle input power
levels up to 0 dBm. R1should realize a minimum attenuation of 31 - 0 = 31 dB. The attenuation realized by R1
and the effective input resistance RIN of the detector equals:
(1)
Solving this expression for R1, using that RIN = 50Ω, yields:
(2)
In Figure 66, R1is set to 1800Ωresulting in an attenuation of 31.4 dB.
22 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
f =
1
2 S (R1 + RIN)C · CIN
C + CIN
PA ANTENNA
RFIN/ENOUT
LMV226/
LMV228
RF
ENABLE
R2
10 k:
VDD
GND
50:
C
100 pF
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
DIRECTIONAL COUPLER APPLICATION
The LMV226/LMV228 also has a 50Ωinput resistance. However, its input range differs compared to the
LMV225, i.e. −15 dBm to +15 dBm. If a typical attenuation of a directional coupler is 20 dB, the LMV226/LMV228
can be directly connected via the directional coupler to the PA without the need of additional external attenuator
(Figure 67). Different PA ranges can be configured using couplers with other coupling factors.
Figure 67. Typical LMV226/LMV228 Application with
Directional Coupler
SHUTDOWN FUNCTIONALITY
The LMV225/LMV226/LMV228 RFIN/ENpins have 2 functions combined:
• Enable/Shutdown
• Power input
The capacitor C and the resistor R2(Figure 66 and Figure 67) separate the DC shutdown functionality from the
AC power measurement. The device is active when Enable = HI, otherwise it is in a low power consumption
shutdown mode. During shutdown the output will be LOW.
Capacitor C should be chosen sufficiently large to ensure a corner frequency far below the lowest input
frequency to be measured. In case of the LMV225 the corner frequency can be calculated using:
where
• RIN = 50Ω, CIN = 45 pF typical (3)
With R1= 1800Ωand C = 100 pF, this results in a corner frequency of 2.8 MHz. This corner frequency is an
indicative number. The goal is to have a magnitude transfer, which is sufficiently flat in the used frequency range;
capacitor C should be chosen significantly larger than capacitor CIN to assure a proper performance of the high
resistive tap. Capacitor C shouldn’t be chosen excessively large since the RC-time, it introduces in combination
with resistor R2, adds to the turn-on time of the device.
The LMV226/LMV228 do not use a resistor R1like the LMV225. Though a resistor is seen on the coupler side
(RCOUPLER). Therefore a similar equation holds for the LMV226/LMV228 LF corner frequency, where R1is
replaced with the coupler output impedance (RCOUPLER).
With RCOUPLER = 50Ωand C = 100 pF, the resulting corner frequency is 50 MHz.
The output voltage is proportional to the logarithm of the input power, often called “linear-in-dB”. Figure 68 shows
the typical output voltage versus PA output power of the LMV225 setup as depicted in Figure 66.
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 23
Product Folder Links: LMV225 LMV226 LMV228
VIN (1 + P
VIN (1 - P
0
VIN
-50 -40 -30 -20 -10 0 10 20 30 40
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
LMV225 OUTPUT VOLTAGE (V)
POWER (dBm)
31.4 dB
LMV225
RF INPUT POWER
PA OUTPUT
POWER
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
Figure 68. Typical power detector response, VOUT vs. PA output Power
OUTPUT RIPPLE DUE TO AM MODULATION
A CDMA modulated carrier wave generally contains some amplitude modulation that might disturb the RF power
measurement used for controlling the PA. This section explains the relation between amplitude modulation in the
RF signal and the ripple on the output of the LMV225/LMV228. Expressions are provided to estimate this ripple
on the output. The ripple can be further reduced by lowpass filtering at the output. This is realized by connecting
an capacitor from the output of the LMV225/LMV228 to ground.
Estimating Output Ripple
The CDMA modulated RF input signal of Figure 68 can be described as:
VIN(t) = VIN [1 + μ(t)] cos (2 · π· f · t)
where
• VIN is the amplitude of the carrier frequency
• Amplitude modulation μ(t) can be between -1 and 1 (4)
Figure 69. AM Modulated RF Signal
24 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
PIN (dBm)
VOUT (V)
PZ
SLOPE = VY
5dB
200mV
VRIPPLE = VY · 20 LOG 1 + P
1 - P
VRIPPLE = VY 10 LOG
VIN2
2RIN
+30
(1 + P)2-VY10 LOG
VIN2(1 - P)2
+30
2RIN
PINMAX IN dBm PINMIN IN dBm
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
The ripple observed at the output of the detector equals the detectors response to the power variation at the
input due to AM modulation (Figure 69). This signal has a maximum amplitude VIN • (1+μ) and a minimum
amplitude VIN • (1-μ), where 1+μcan be maximum 2 and 1-μcan be minimum 0. The amplitude of the ripple can
be described with the formula:
where
• VYis the slope of the detection curve (Figure 70)
•μis the modulation index (5)
Equation 5 can be reduced to:
(6)
Consequently, the ripple is independent of the average input power of the RF input signal and only depends on
the logarithmic slope VYand the ratio of the maximum and the minimum input signal amplitude.
For CDMA, the ratio of the maximum and the minimum input signal amplitude modulation is typically in the order
of 5 to 6 dB, which is equivalent to a modulation index μof 0.28 to 0.33.
A further understanding of the equation above can be achieved via the knowledge that the output voltage VOUT of
the LMV225/LMV228 is linear in dB, or proportional to the input power PIN in dBm. As discussed earlier, CDMA
has a modulation in the order of 5 to 6 dB. Since the transfer is linear in dB, the output voltage VOUT will vary
linearly over about 5 to 6 dB in the curve (Figure 70).
Figure 70. VOUT vs. RF Input Power PIN
The output voltage variation ΔVOUT is thus identical for RF input signals that fall within the linear range (in dB) of
the detector. In other words, the output variation is independent of the absolute RF input signal:
ΔVO= VY·ΔPIN (7)
In which VYis the slope of the curve. The log-conformance error is usually much smaller than the ripple due to
AM modulation. In case of the LMV225/LMV228, VY= 40 mV/dB. With ΔPIN = 5 dB for CDMA, ΔVOUT = 200
mVPP. This is valid for all VOUT.
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 25
Product Folder Links: LMV225 LMV226 LMV228
A/0 A/0 A/0 A/0
X4
X3
X2
X1
X0
+ + + +
Y
1000
100
10
1-50 -40 -30 -20 -10 0 10
RF INPUT POWER (dBm)
OUTPUT RIPPLE (mVPP)
NO ADDITIONAL CAPACITOR
COUT = 1.5nF
fC = 1
2 S COUT RO
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
Output Ripple with Additional Filtering
The calculated result above is for an unfiltered configuration. When a low pass filter is used by shunting a
capacitor of e.g. COUT = 1.5 nF at the output of the LMV225/LMV228 to ground, this ripple is further attenuated.
The cut-off frequency follows from:
(8)
With the output resistance of the LMV225/LMV228 RO= 19.8 kΩtypical and COUT = 1.5 nF, the cut-off frequency
equals fC= 5.36 kHz. A 100 kHz AM signal then gets attenuated by 5.36/100 or 25.4 dB. The remaining ripple
will be less than 20 mV. With a slope of 40 mV/dB this translates into an error of less than ±0.5 dB. Since the
LMV226 has a low output impedance buffer, a capacitor to reduce the ripple will not be effective.
Output Ripple Measurement
Figure 71 shows the ripple reduction that can be achieved by adding additional capacitance at the output of the
LMV225/LMV228. The RF signal of 900 MHz is AM modulated with a 100 kHz sinewave and a modulation index
of 0.3. The RF input power is swept while the modulation index remains unchanged. Without the output capacitor
the ripple is about 200 mVPP. Connecting a capacitor of 1.5 nF at the output to ground, results in a ripple of 12
mVPP. The attenuation with a 1.5 nF capacitor is then 20 • log (200/12) = 24.4 dB. This is very close to the
calculated number of the previous paragraph.
Figure 71. Output Ripple vs. RF Input Power
PRINCIPLE OF OPERATION
The logarithmic response of the LMV225/LMV226/LMV228 is implemented by a logarithmic amplifier as shown in
Figure 72. The logarithmic amplifier consists of a number of cascaded linear gain cells. With these gain cells, a
piecewise approximation of the logarithmic function is constructed.
Figure 72. Logarithmic Amplifier
26 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
EK
EK/A1
EK/A2
EK/A3
Y = X
Y = AX
Y = A2X
Y = A3X
X (Log)
Y
Y = LOG (X)
EK/A3
EK/A2
EK/A1EK
X (LIN)
Y
y
x
EKx
y
xA
x0
A/0
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
Every gain cell has a response according to Figure 73. At a certain threshold (EK), the gain cell starts to saturate,
which means that the gain drops to zero. The output of gain cell 1 is connected to the input of gain cell 2 and so
on.
Figure 73. Gain Cell
All gain cell outputs are AM-demodulated with a peak detector and summed together. This results in a
logarithmic function. The logarithmic range is about:
20 · n · log (A)
where
• n = number of gain cells
• A = gain per gaincell (9)
Figure 74 shows a logarithmic function on a linear scale and the piecewise approximation of the logarithmic
function.
Figure 74. Log-Function on Lin Scale
Figure 75 shows a logarithmic function on a logarithmic scale and the piecewise approximation of the logarithmic
function.
Figure 75. Log-Function on Log Scale
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 27
Product Folder Links: LMV225 LMV226 LMV228
EK
A2·EK
A1=EK
AA
LMV225, LMV226, LMV228
SNWS013L –AUGUST 2003–REVISED MARCH 2013
www.ti.com
The maximum error for this approximation occurs at the geometric mean of a gain section, which is e.g. for the
third segment:
(10)
The size of the error increases with distance between the thresholds.
LAYOUT CONSIDERATIONS
For a proper functioning part a good board layout is necessary. Special care should be taken for the series
resistance R1(Figure 66) that determines the attenuation. For high resistor values the parasitic capacitance of
the resistor may significantly impact the realized attenuation. The effective attenuation will be lower than
intended. To reduce the parasitic capacitance across resistor R1, this resistor can be composed of several
components in series instead of using a single component.
28 Submit Documentation Feedback Copyright © 2003–2013, Texas Instruments Incorporated
Product Folder Links: LMV225 LMV226 LMV228
LMV225, LMV226, LMV228
www.ti.com
SNWS013L –AUGUST 2003–REVISED MARCH 2013
REVISION HISTORY
Changes from Revision K (March 2013) to Revision L Page
• Changed layout of National Data Sheet to TI format .......................................................................................................... 28
Copyright © 2003–2013, Texas Instruments Incorporated Submit Documentation Feedback 29
Product Folder Links: LMV225 LMV226 LMV228
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead finish/
Ball material
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
LMV225SD/NOPB ACTIVE WSON NGF 6 1000 RoHS & Green SN Level-1-260C-UNLIM -40 to 85 A90
LMV225SDX/NOPB NRND WSON NGF 6 4500 RoHS & Green SN Level-1-260C-UNLIM -40 to 85 A90
LMV225TL/NOPB ACTIVE DSBGA YZR 4 250 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 85
LMV225TLX/NOPB ACTIVE DSBGA YZR 4 3000 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 85
LMV225UR/NOPB ACTIVE DSBGA YPD 4 250 RoHS & Green SNAGCU Level-1-260C-UNLIM
LMV225URX/NOPB ACTIVE DSBGA YPD 4 3000 RoHS & Green SNAGCU Level-1-260C-UNLIM
LMV226TL/NOPB ACTIVE DSBGA YZR 4 250 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 85
LMV226TLX/NOPB ACTIVE DSBGA YZR 4 3000 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 85
LMV226UR/NOPB ACTIVE DSBGA YPD 4 250 RoHS & Green SNAGCU Level-1-260C-UNLIM
LMV228SD/NOPB ACTIVE WSON NGF 6 1000 RoHS & Green SN Level-1-260C-UNLIM A89
LMV228TL/NOPB ACTIVE DSBGA YZR 4 250 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 85
LMV228TLX/NOPB ACTIVE DSBGA YZR 4 3000 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 85
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 2
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two
lines if the finish value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LMV225SD/NOPB WSON NGF 6 1000 178.0 12.4 2.8 2.5 1.0 8.0 12.0 Q1
LMV225SDX/NOPB WSON NGF 6 4500 330.0 12.4 2.8 2.5 1.0 8.0 12.0 Q1
LMV225TL/NOPB DSBGA YZR 4 250 178.0 8.4 1.09 1.09 0.76 4.0 8.0 Q1
LMV225TLX/NOPB DSBGA YZR 4 3000 178.0 8.4 1.09 1.09 0.76 4.0 8.0 Q1
LMV225UR/NOPB DSBGA YPD 4 250 178.0 8.4 1.04 1.04 0.56 4.0 8.0 Q1
LMV225URX/NOPB DSBGA YPD 4 3000 178.0 8.4 1.04 1.04 0.56 4.0 8.0 Q1
LMV226TL/NOPB DSBGA YZR 4 250 178.0 8.4 1.09 1.09 0.76 4.0 8.0 Q1
LMV226TLX/NOPB DSBGA YZR 4 3000 178.0 8.4 1.09 1.09 0.76 4.0 8.0 Q1
LMV226UR/NOPB DSBGA YPD 4 250 178.0 8.4 1.04 1.04 0.56 4.0 8.0 Q1
LMV228SD/NOPB WSON NGF 6 1000 178.0 12.4 2.8 2.5 1.0 8.0 12.0 Q1
LMV228TL/NOPB DSBGA YZR 4 250 178.0 8.4 1.09 1.09 0.76 4.0 8.0 Q1
LMV228TLX/NOPB DSBGA YZR 4 3000 178.0 8.4 1.09 1.09 0.76 4.0 8.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 29-Sep-2019
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LMV225SD/NOPB WSON NGF 6 1000 210.0 185.0 35.0
LMV225SDX/NOPB WSON NGF 6 4500 367.0 367.0 35.0
LMV225TL/NOPB DSBGA YZR 4 250 210.0 185.0 35.0
LMV225TLX/NOPB DSBGA YZR 4 3000 210.0 185.0 35.0
LMV225UR/NOPB DSBGA YPD 4 250 210.0 185.0 35.0
LMV225URX/NOPB DSBGA YPD 4 3000 210.0 185.0 35.0
LMV226TL/NOPB DSBGA YZR 4 250 210.0 185.0 35.0
LMV226TLX/NOPB DSBGA YZR 4 3000 210.0 185.0 35.0
LMV226UR/NOPB DSBGA YPD 4 250 210.0 185.0 35.0
LMV228SD/NOPB WSON NGF 6 1000 210.0 185.0 35.0
LMV228TL/NOPB DSBGA YZR 4 250 210.0 185.0 35.0
LMV228TLX/NOPB DSBGA YZR 4 3000 210.0 185.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 29-Sep-2019
Pack Materials-Page 2
www.ti.com
PACKAGE OUTLINE
C
0.395 MAX
0.155
0.115
0.5
0.5
4X 0.295
0.255
B E A
D
4215141/B 08/2016
DSBGA - 0.395 mm max heightYPD0004
DIE SIZE BALL GRID ARRAY
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
SYMM
SYMM
BALL A1
CORNER
SEATING PLANE
BALL TYP 0.05 C
12
0.015 C A B
A
B
SCALE 14.000
D: Max =
E: Max =
0.998 mm, Min =
0.996 mm, Min =
0.938 mm
0.936 mm
www.ti.com
EXAMPLE BOARD LAYOUT
4X ( 0.265)
( 0.265)
METAL 0.05 MAX
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
( 0.265)
SOLDER MASK
OPENING
0.05 MIN
(0.5)
(0.5)
4215141/B 08/2016
DSBGA - 0.395 mm max heightYPD0004
DIE SIZE BALL GRID ARRAY
NOTES: (continued)
3. Final dimensions may vary due to manufacturing tolerance considerations and also routing constraints.
See Texas Instruments Literature No. SNVA009 (www.ti.com/lit/snva009).
SOLDER MASK DETAILS
NOT TO SCALE
12
A
B
SYMM
SYMM
LAND PATTERN EXAMPLE
SCALE:40X
NON-SOLDER MASK
DEFINED
(PREFERRED) SOLDER MASK
DEFINED
www.ti.com
EXAMPLE STENCIL DESIGN
4X ( 0.25) (R0.05) TYP
METAL
TYP
(0.5) TYP
(0.5) TYP
4215141/B 08/2016
DSBGA - 0.395 mm max heightYPD0004
DIE SIZE BALL GRID ARRAY
NOTES: (continued)
4. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release.
12
A
B
SYMM
SYMM
SOLDER PASTE EXAMPLE
BASED ON 0.1 mm THICK STENCIL
SCALE:50X
MECHANICAL DATA
YZR0004xxx
www.ti.com
TLA04XXX (Rev D)
0.600±0.075 D
E
4215042/A 12/12
A
. All linear dimensions are in millimeters. Dimensioning and tolerancing per ASME Y14.5M-1994.
B. This drawing is subject to change without notice.
NOTES:
D: Max =
E: Max =
1.057 mm, Min =
1.057 mm, Min =
0.996 mm
0.996 mm
MECHANICAL DATA
NGF0006A
www.ti.com
IMPORTANT NOTICE AND DISCLAIMER
TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATASHEETS), DESIGN RESOURCES (INCLUDING REFERENCE
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD
PARTY INTELLECTUAL PROPERTY RIGHTS.
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable
standards, and any other safety, security, or other requirements. These resources are subject to change without notice. TI grants you
permission to use these resources only for development of an application that uses the TI products described in the resource. Other
reproduction and display of these resources is prohibited. No license is granted to any other TI intellectual property right or to any third
party intellectual property right. TI disclaims responsibility for, and you will fully indemnify TI and its representatives against, any claims,
damages, costs, losses, and liabilities arising out of your use of these resources.
TI’s products are provided subject to TI’s Terms of Sale (www.ti.com/legal/termsofsale.html) or other applicable terms available either on
ti.com or provided in conjunction with such TI products. TI’s provision of these resources does not expand or otherwise alter TI’s applicable
warranties or warranty disclaimers for TI products.
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2020, Texas Instruments Incorporated