LMV243
Single-Channel, Quad-Band GSM Power Controller in
micro SMD
LMV243 Single-Channel, Quad-Band GSM Power Controller in micro SMD
May 2002
General Description
The device is intended for use within an RF transmit power
control loopin GSM mobile phones and supports GaAs HBT
and bipolar RF single supply power amplifiers. The circuit
operates with a single supply from 2.7V to 3.3V.
The LMV243 contains an RF detector, error amplifier, ramp
V/I converter and output driver. The LMV243 input interface
consists of the RF input, Ramp voltage, and a digital input to
perform the function ’Shutdown/Transmit Enable’. The device will be active in the case TX_EN = HI, otherwise, the
device goes into a low power consumption shutdown mode.
During shutdown the output will be in high impedance
(tri-state).
A single external RC combination is used to provide stable
operations that accommodates individual PA characteristics.
The LMV243 is offered in a 8-bump micro SMD 1.5mm x
1.5mm package. This space savings package supports flexible product placement almost anywhere in the circuitboard.
Typical Application
Features
(Typical Unless Otherwise Noted)
n 50dB RF detection range (typical)
n micro SMD package 1.5mm x 1.5mm x 0.995mm
n Support of GaAs HBT, bipolar technology
n Quad-band operation
n Shutdown mode for Power Save in Rx slot
n GPRS compliant
n External loop compensation option
n Accurate temperature compensation
n Frequency range is 450MHz to 2GHz
Applications
n GSM mobile phone
n AGC for digital audio
n TDMA RF control
n Wireless LAN
RF Input Power Range (Note 5)20kΩ // 27pF between V
and V
COMP
OUT
−50
+5
−63
dBm
dBV
−7
Logarithmic Slope (Note 9)
Logarithmic Intercept (Note 9)
R
IN
C
IN
DC Resistance(Note 8)50Ω
Input Capacitance(Note 8)0.5pF
@
900MHz, 20kΩ // 27pF
between V
@
1800MHz, 20kΩ // 27pF
between V
@
1900MHz, 20kΩ // 27pF
between V
@
900MHz, 20kΩ // 27pF
between V
@
1800MHz, 20kΩ // 27pF
between V
@
1900MHz, 20kΩ // 27pF
between V
OUT
OUT
OUT
OUT
OUT
OUT
and V
and V
and V
and V
and V
and V
COMP
COMP
COMP
COMP
COMP
COMP
−1.79
−1.89
−1.89
−50.5
−46.9
−45.9
µa/dB
dBm
Error Amplifier
GBWGain-Bandwidth Product(Note 8)7.6MHz
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LMV243
Electrical Characteristics Unless otherwise specified, all limits are guaranteed to T
= 25˚C. VDD= 2.8V.
J
Boldface limits apply at temperature extremes. (Continued)
SymbolParameterConditionMinTypMaxUnits
V
O
Output Swing from RailSourcing, IO= 5mA5585
105
Sinking, I
= −5mA4575
O
mV
95
I
O
e
n
Output Short Circuit Current
(Note 3)
Sourcing, VO=0V25145
Sinking, V
= 2.8V25180
O
Output Referred NoiseRF input = 1800 MHz,
mA
700nV/
-10dBm, 20kΩ // 27pF
between V
=1.4V, set by V
V
OUT
OUT
and V
COMP
RAMP
,
,
(Note 8)
SRSlew Rate8
11V/µs
5
Note 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 guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics.
Note 2: Human body model: 1.5kΩ in series with 100pF. Machine model, 0Ω in series with 100pF.
Note 3: Shorting circuit output to either V
Note 4: 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 T
Note 5: Power in dBV = dBm + 13 when the impedance is 50Ω.
Note 6: The maximum power dissipation is a function of T
(T
J(MAX)-TA
Note 7: All limits are guaranteed by design or statistical analysis
Note 8: Typical values represent the most likely parametric norm.
Note 9: Slope and intercept are calculated from graphs ’V
)/θJA. All numbers apply for packages soldered directly into a PC board
. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self-heating where T
J=TA
+
or V−will adversely affect reliability.
, θJAand TA. The maximum allowable power dissipation at any ambient temperature is PD=
J(MAX)
vs. RF input Power’ where the current is obtained by division of the voltage by 20kΩ.
OUT
J
>
TA.
Connection Diagram
8-Bump micro SMD
20029035
Top View
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Pin Descriptions
LMV243
Power SupplyA3V
Digital InputsC2TX_ENA Logic High to enable device.
Analog InputsB3RF INRF Input connected to the Coupler output with optional attenuation to measure the
Compensation A1CompConnects an external RC network between the Comp pin and the Output pin for an
OutputB1OutA rail-to-rail output capable of sourcing 25mA and sinking 25mA, with less than 200mV
Note: 1. All inputs and outputs are referenced to GND (pin A2, C3).
2. For the digital inputs, a LOW is
3. RF power detection is performed internally in the LMV243 and only an RF power coupler with optional extra attenuation has to be used.
PinNameDescription
DD
Supply Voltage
A2, C3GNDPower Ground. Operation requires both pins be grounded.
Power Amplifier (PA) / Antenna RF power levels.
C1RAMP INSets the RF output power level. The useful input voltage range is from 0.2V to 1.8V,
although voltages from 0V to V
are allowed.
DD
overall loop compensation and to control the closed loop frequency response.
Conventional loop stability techniques can be used in selecting this network, such as
Bode plots. A good starting value for the RC combination will be C = 68pF andR=0Ω.
total voltage drop over the specified temperature. The output is free from glitches when
enabled by TX_EN. When TX_EN is low, the output voltage is near GND.