LMH2110 8-GHz Logarithmic RMS Power Detector with 45-dB Dynamic Range
1 Features
- Wide Supply Range from 2.7 V to 5 V
- Logarithmic Root Mean Square Response
- 45-dB Linear-in-dB Power Detection Range
- Multi-Band Operation from 50 MHz to 8 GHz
- LOG Conformance Better than ±0.5 dB
- Highly Temperature Insensitive, ±0.25 dB
- Modulation Independent Response, 0.08 dB
- Minimal Slope and Intercept Variation
- Shutdown Functionality
- Tiny 6-Bump DSBGA Package
2 Applications
- Multi-Mode, Multi-Band RF Power Control
- GSM/EDGE
- CDMA/CDMA2000
- W-CDMA
- OFDMA
- LTE
- Infrastructure RF Power Control
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3 Description
The LMH2110 is a 45-dB Logarithmic RMS power detector particularly suited for accurate power measurement of modulated RF signals that exhibit large peak-to-average ratios; that is, large variations of the signal envelope. Such signals are encountered in W-CDMA and LTE cell phones. The RMS measurement topology inherently ensures a modulation insensitive measurement.
The device has an RF frequency range from 50 MHz to 8 GHz. It provides an accurate, temperature and supply insensitive output voltage that relates linearly to the RF input power in dBm. The LMH2110 device has excellent conformance to a logarithmic response, enabling easy integration by using slope and intercept only, reducing calibration effort significantly. The device operates with a single supply from 2.7 V to
5 V. The LMH2110 has an RF power detection range from –40 dBm to 5 dBm and is ideally suited for use in combination with a directional coupler. Alternatively, a resistive divider can be used.
The device is active for EN = High; otherwise, it is in a low power-consumption shutdown mode. To save power and prevent discharge of an external filter capacitance, the output (OUT) is high-impedance during shutdown.
Device Information(1)
| PART NUMBER | PACKAGE | BODY SIZE (MAX) |
|---|---|---|
| LMH2110 | DSBGA (6) | 1.27 mm × 0.87 mm |
- For all available packages, see the orderable addendum at the end of the data sheet.
Typical Application Circuit
Output Voltage and Log Conformance Error vs.
RF Input Power at 1900 MHz
4 Revision History
Changes from C Revision (March 2013) to D Revision
- Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section Go
Changes from B Revision (October 2013) to C Revision
- Changed layout of National Data Sheet to TI formatGo
5 Pin Configuration and Functions
Pin Functions
| PIN | TYPE | DESCRIPTION | |
|---|---|---|---|
| NUMBER | NAME | ||
| A1 | VDD | Power Supply | Positive supply voltage. |
| A2 | OUT | Output | Ground referenced detector output voltage. |
| B1 | RFIN | Analog Input | RF input signal to the detector, internally terminated with 50 Ω. |
| B2 | GND | Power Supply | Power Ground. May be left floating in case grounding is not feasible. |
| C1 | GND | Power Supply | Power Ground. |
| C2 | EN | Logic Input | The device is enabled for EN = High, and in shutdown mode for EN = Low. EN must be < 2.5 V to have low IEN. For EN > 2.5 V, IEN increases slightly, while device is still functional. Absolute maximum rating for EN = 3.6 V. |