Download WS1050 Tunable RF Capacitor

WS1050 Tunable
RF Capacitor
Applications
General Description
Technology
The WS1050 tunable RF capacitor
combines three individually addressable
capacitors into a single chip. The device
reduces cost, board space, and design
time while improving linear performance
and design flexibility. It enables very
small, narrow-band antennas to be tuned
over a wide frequency range, while
eliminating the need for a separate Long
Term Evolution (LTE) antenna.
Each CMOS-integrated capacitor is
tunable from 0.6 to 6.0pf – in step sizes of
1/10th pf – for 18pf of total capacitance.
These highly flexible capacitors can be
configured individually in series or shunt,
with an individual pin-out for each
capacitor.
• Mobile devices including
smartphones, feature phones
and tablets
• Wireless infrastructure
equipment including
basestations, picocells,
femtocells, and WiFi routers
• Current network architectures
including LTE and LTE
Advanced
• Future network architectures
including 600mHz
• Measurement/Test
instruments, phase shifters
• Tunable filters and amplifiers
WiSpry’s unique capacitor offers benefits
for both mobile device and wireless
infrastructure OEMs. Smartphone
designers can now design once for
multiple product iterations. For
basestations, picocells, femtocells and
WiFi routers, the WS1050 enables
designers to address complex signal
mismatch environments.
The WS1050 delivers the industry’s
highest Q, offering the widest impedance
coverage and lowest loss. This
exceptional performance enables
designers to tune for the highest
“mismatched” conditions, including
challenging form factors and non-ideal
environments. The linear performance of
the chip produces third harmonics as low
as 150dBc, achieved by the chip’s
proprietary MEMS-based technology.
Features
• Tune antennas and amplifiers
for signal chain gains up to
3dB
• Eliminates a separate LTE
antenna
• Completely integrated
solution saves board space
and external component cost
• Broadband antenna tuning
IMAGE PLACEHOLDER
with an SRF above 3.5gHz
WS1050 simplified block diagram
WS1050 Tunable RF Capacitor
Hardware Selectable USID Feature
The RFFE interface can be configured to be backwards
compatible with earlier generation WiSpry parts. In addition,
the WS1050 adds six extra slave identifiers for a total of
eight as per the MIPI® Alliance RFFE specification.
Compact LGA Package & System Solution
With full integration and minimal number of external
components required, WS1050 can be used in the smallest
form factor designs.
Tunable Capacitor Function
Hardware Wakeup – XCTRL Pin
Functionality
Serial Interface Control
WS1050 features a hardware control pin, allowing control of
the charge pump without using the control bus.
The WS1050 features a serial interface that is compatible
with MIPI® RFFE1.1 signaling. The serial interface controls
the WS1050 operating mode as well as the capacitor
settings.
Capacitor Configuration
The WS1050 contains three high–Q, high linearity, tunable
series MEMS capacitors. All capacitors are series configuration (both terminals are floating) and thus can be used
in series or shunt configuration. This enables use in L and π
type networks as well as bundled into one or several large
series or shunt capacitors.
Each capacitor is digitally controllable between the values
Cmin and Cmax and steps in capacitance with the miniumum step size LSB.
ROHS
The WS1050 is compliant with lead free requirements of the
Directive 2002/95/EC of the European Parliament and of the
Council on the restriction of hazardous substances in
electrical and electronic equipment (“RoHS”).
WS1050 Tunable RF Capacitor
Recommended Application Schematic
Electrical Characteristics
Description / Conditions
TYP
Units
2.5 – 5.0
V
Supply Current Standby
1.0
A
Supply Current Active, Average
38
A
Supply Voltage Operating Range
0.5 – 6.0
pF
Smallest Capacitance Step
0.1
pF
Capacitor Q, Mid setting @ 800 MHz
150
Second Order Harmonic at Cmax Setting, 24 dBm Input
Power
-110
dBm
Third Order Harmonic at Cmax Setting, 24 dBm Input Power
-130
dBm
Serial Interface Input Clock Frequency maximum
26
MHz
MIPI® RFFE Reference Voltage
1.8
V
Capacitance range, per bank
MIPI® specifications and trademarks are property of MIPI®
Alliance, Inc.
WiSpry, Inc.
WS1050 - 1113
20 Fairbanks #198, Irvine, CA 92618
+1 949 458 9477
Copyright 2013 WiSpry, Inc. All Rights Reserved.
www.wispry.com