DESCRIPCIÓN GENERAL

The ADMV1013 is a wideband, microwave upconverter optimized for point to point microwave radio designs operating in the 24 GHz to 44 GHz radio frequency (RF) range.  The upconverter offers two modes of frequency translation. The device is capable of direct conversion to RF from baseband in-phase quadrature (I/Q) input signals, as well as single-sideband (SSB) upconversion from complex intermediate frequency (IF) inputs. The baseband I/Q input path can be disabled and modulated complex IF signals, anywhere from 0.8 GHz to 6.0 GHz, can be inserted in the IF path and upconverted to 24 GHz to 44 GHz  while suppressing the unwanted sideband by typically better than 26 dBc. The serial port interface (SPI) allows adjustment of the quadrature phase and mixer gate voltage to allow optimum sideband suppression and local oscillator (LO) nulling. In addition, the SPI interface allows powering down the output envelope detector to reduce power consumption. The ADMV1013 upconverter comes in a 40-terminal land grid array package (LGA) package. The ADMV1013 operates over the −40°C to +85°C case temperature range.

 

CARACTERÍSTICAS

Wideband RF input frequency range: 24 GHz to 44 GHz

2 upconversion modes Direct conversion from baseband I/Q to RF Single-sideband upconversion from real IF

LO input frequency range: 5.4 GHz to 10.25 GHz

LO quadrupler for up to 41 GHz

Matched 50 Ω single-ended RF output and IF inputs

Option between matched 100 Ω balanced or 50 Ω single

ended LO inputs

100 Ω balanced baseband inputs

Sideband suppression and carrier feedthrough optimization

Variable attenuator for transceiver power control

Programmable via 4-wire SPI interface

40-terminal land grid array package (LGA)

 

APLICACIONES

Radios de microondas punto a punto

Radar, electronic warfare systems

Instrumentation, automatic test equipment (ATE)

 

TEORÍA DE FUNCIONAMIENTO

The ADMV1013 is a wideband microwave upconverter optimized for microwave radio designs operating in the 24 GHz to 44 GHz RF frequency range. See Figure 1 for a functional block diagram of the device. The ADMV1013 digital settings are controlled via the SPI. The ADMV1013 has two modes of operation:

  • Baseband quadrature modulation (I/Q mode)
  • Single-sideband upconversion (IF mode)

START-UP SEQUENCE

To use the voltage control RF VVA1 and RF VVA2, the VCC_VVA (1.8 V) supply must be on. The VCTRL1 pin and VCTRL2 pin control the gain of the RF VVA1 and the RF VVA2. Similarly, to use the SPI control, it is necessary to first turn on DVDD and then perform a hard reset by toggling the RST pin to logic low and then to logic high. The ADMV1013 SPI settings require the default settings to be changed during startup for optimum performance.  Set Register 0x0A to 0xE700 after each power-up or reset. BASEBAND QUADRATURE MODULATION (I/Q MODE) In I/Q mode, the input impedance of the baseband pins (I_P, I_N, Q_P, and Q_N) are 100 Ω differential. These inputs can be loaded with a dc-coupled 100 Ω differential load. I_P and I_N are the differential baseband I inputs, and Q_P and Q_N are the differential baseband Q inputs. These inputs can operate from a VCM of 0 V to 2.6 V. The baseband I/Q ports can operate from dc to 6.0 GHz at each I and Q channel. To set the ADMV1013 in I/Q mode, set MIXER_IF_EN bit (Register 0x03, Bit 7) to 0. When changing the external VCM, the internal mixer gate voltage also must be changed. To make this change, set the MIXER_VGATE bits (Register 0x05, Bits[6:0]). The MIXER_ VGATE value follows the VCM such as, that for a 0 V to 1.8 V VCM, MIXER_VGATE = 23.89 VCM + 81, and for a >1.8 V to 2.6 V VCM, MIXER_VGATE = 23.75 VCM + 1.25.

SINGLE-SIDEBAND UPCONVERSION (IF MODE)

The ADMV1013 features the ability to upconvert a real IF input anywhere from 0.8 GHz to 6.0 GHz while suppressing the unwanted sideband by typically better than 26 dBc. The IF inputs are quadrature to each other, 50 Ω single ended, and are internally dc-coupled. IF_I and IF_Q are the quadrature IF inputs. An external 90° hybrid is required to select the appropriate sideband. To configure the ADMV1013 in IF mode, set the MIXER_IF_EN bit (Register 0x03, Bit 7) to 1. The MIXER_IF_EN bit defaults to IF mode on SPI startup and reset.  In addition, the baseband pins (I_P, I_N, Q_P, and Q_N) must see an open load for optimum performance in IF mode.