LT5512_15 Datasheet, PDF (1/12 Pages) Linear Technology – 1kHz-3GHz High Signal Level Active Mixer

LT5512
1kHz-3GHz High Signal Level
Active Mixer
FEATURES
■ _{Broadband RF, LO and IF Operation}
■ _{High Input IP3: >20dBm from 30MHz to 900MHz}
+17dBm at 1900MHz
■ _{Typical Conversion Gain: 1dB}
■ _{SSB Noise Figure: 11dB at 900MHz}
14dB at 1900MHz
■ _{Integrated LO Buffer: Insensitive to LO Drive Level}
■ _{Single-Ended or Differential LO Drive}
■ _{High LO-RF Isolation}
■ _{Enable Function}
■ _{4.5V to 5.25V Supply Voltage Range}
■ _{4mm × 4mm QFN Package}
U
APPLICATIO S
■ _{HF/VHF/UHF Mixer}
■ _{Cellular/PCS/UMTS Infrastructure}
■ _{High Linearity Mixer Applications}
■ _{ISM Band Receivers}
■ _{Wireless Medical Telemetry System (WMTS)}
DESCRIPTIO
The LT^®5512 is an active double-balanced mixer IC, op-
timized for high linearity HF, VHF and UHF applications.
The IC includes an integrated LO buffer amplifier to drive
the mixer and an RF buffer amplifier for improved LO-RF
isolation. Internal bias circuits eliminate the need for
precision external resistors and allow the device to be
powered-down using the enable control (EN) pin.
The externally matched RF and IF ports allow the mixer
to be used at very low frequencies, below 1MHz or up to
3GHz. The differential LO input is designed for single-ended
or a differential input drive.
The LT5512 is a high-linearity alternative to passive diode
mixers. Unlike passive mixers, which have conversion
loss and require high LO drive levels, the LT5512 deliv-
ers conversion gain and requires significantly lower LO
drive levels.
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATIO
High Signal-Level Downmixer for 600MHz Wireless Medical Telemetry System
LO_IN
–5dBm TYP
0.01µF
0.01µF
100Ω
RF_IN
608MHz
TO 614MHz
50Ω
47nH
6.8nH
LO⁺
LT5512
RF⁺
6.8pF
6.8nH
EN
5V
RF ^–
6.8pF
BIAS
EN V_CC2
LO–
IF⁺
8:1
1.8pF
IF ^–
V_CC1
0.01µF
1µF
IF_OUT
45MHz
50Ω
V_CC
4.5V TO 5.25V
5512 TA01
Conv Gain, IIP3, NF and
LO Leakage vs LO Power
21
19 ^IIP3
17
15
13
11 _{SSB NF}
9
7
5
3
1 ^GC
–11 –9
20
T_A = 25°C
RF = 610MHz 0
HIGH-SIDE LO
IF = 45MHz
–20
–40
LO-IF
LO-RF
–60
–7 –5 –3
LO POWER (dBm)
–80
–1 1
5512 TA01a
5512fa
1