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Preliminary Information
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This document contains information on a new product. The parametric information, although not fully characterized, is the result of testing initial devices.
The CX77301 is a dual-band Power Amplifier Module (PAM) designed in a compact form factor for Class 4 EGSM900 and Class 1 DCS1800 operation that also supports multi-slot transmission for Class 10 General Packet Radio Service (GPRS) operation.
*
The module consists of an EGSM900 PA block, a DCS1800 PA block, impedance matching circuitry for 50 input and output impedances, and bias control circuitry. Two separate Heterojunction Bipolar Transistor (HBT) PA blocks are fabricated on a single Gallium Arsenide (GaAs) die. One PA block operates in the EGSM900 band and the other PA block supports the DCS1800 band. Optimized for lithium ion battery operation, both PA blocks share common power supply pins to distribute current. A custom CMOS integrated circuit provides the internal interface circuitry, including a current amplifier that minimizes the required power control current (IAPC) to 10 A, typical. The GaAs die, the Silicon (Si) die, and passive components are mounted on a multi-layer laminate substrate. The assembly is encapsulated with plastic overmold.
The RF input and output ports are internally matched to 50 to reduce the number of external components for a dual-band design. Extremely low leakage current (2 A, typical) of the dual PA module maximizes handset standby time. The CX77301 also contains band-select switching circuitry to select EGSM (logic 0) or DCS (logic 1) as determined from the Band Select (BS) signal. In the Functional Block Diagram shown below, the BS pin selects the PA output (DCS OUT or EGSM OUT) while the Analog Power Control (APC) controls the level of output power.
Functional Block Diagram
DCS IN
m o .c U t4 e e h S ta a .D w w w
* * * *
*
High efficiency: EGSM 55% DCS 50% Input/output matching 50 internal Small outline 9.1 mm x 11.6 mm Low profile 1.5 mm maximum Low APC current 10 A typical Gold plated, lead-free contacts.
Applications
*
Dual-band cellular handsets encompassing Class 4 EGSM900, Class 1 DCS1800, and up to Class 10 GPRS multi-slot operation.
VCC
Match
Match
Power Control Band Select
CMOS Bias Controller Match
HBT
EGSM IN
Match
Data Sheet (c) 2001, Conexant Systems, Inc., All Rights Reserved.
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DCS OUT EGSM OUT
100956D January 2, 2002
Electrical Specifications
CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Electrical Specifications
The following tables list the electrical characteristics of the CX77301 Power Amplifier. Table 1 lists the absolute maximum ratings and Table 2 shows the recommended operating conditions. Table 3 shows the electrical characteristics of the CX77301 for EGSM and DSC modes. A typical CX77301 application diagram appears in Figure 1. The CX77301 is a static-sensitive electronic device and should not be stored or operated near strong electrostatic fields. Detailed ESD precautions along with information on device dimensions, pin descriptions, packaging and handling can be found in later sections of this data sheet.
Table 1. Absolute Maximum Ratings Parameter
Input power (PIN) Supply voltage (VCC), standby, VAPC 0.3 V Control voltage (VAPC) Storage Temperature
Minimum
-- -- -0.5 -55
Maximum
15 7 VCC_MAX - 0.2 (See Table 3) +100
Unit
dBm V V C
Table 2. CX77301 Recommended Operating Conditions Parameter
Supply Voltage (VCC) Supply Current (ICC) Operating Case Temperature (TCASE) 1-Slot (12.5% duty cycle) 2-Slot (25% duty cycle) 3-Slot (37.5% duty cycle) 4-Slot ( 50% duty cycle)
NOTE(S):
(1)
Minimum
2.9 0
Typical
3.5 -- --
Maximum
4.8 V(1) 2.5(1)
Unit
V A
-20 -20 -20 -20
100 90 75 60
C
For charging conditions with VCC > 4.8 V, derate Icc linearly down to 0.5 A max at VCC = 5.5 V
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CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Table 3. CX77301 Electrical Specifications (1 of 4)(1) Parameter Symbol Test Condition General
Supply Voltage Power Control Current Leakage Current VCC IAPC Iq VCC = 4.5 V VAPC = 0.3 V TCASE = +25 C PIN -60 dBm -- Time from VAPC VAPCTH until POUT (POUT_FINAL -3 dB) -- -- 2.9 -- --
Electrical Specifications
Min
Typical
Max
Units
3.5 10 --
4.8V 100 5
V A A
APC Enable Threshold APC Enable Switching Delay
VAPCTH tSW
200 5
--
600 8
mV s
EGSM Mode (f = 880 to 915 MHz and PIN = 6 to 12 dBm)
Frequency Range Input Power Analog Power Control Voltage Power Added Efficiency) f PIN VAPC PAE POUT = 32 dBm VCC = 3.5 V POUT 34.5 dBm VAPC 2.0 V, pulse width = 577 s, duty cycle = 1:8 TCASE = +25 C BW = 3 MHz 5 dBm POUT 35 dBm VCC = 3.5 V VAPC 2.0 V TCASE = +25 C VCC = 2.9 V VAPC 2.6 V TCASE = -20 C to +100 C (See Table 2 for multi-slot) PIN = 6 dBm VCC = 4.8 V VAPC 2.6 V TCASE = -20 C to +100 C (See Table 2 for multi-slot) PIN = 6 dBm POUT = 5 to 35 dBm, controlled by VAPC PIN = 12 dBm, VAPC= 0.3 V -- -- 880 6 1.2 50 -- -- 1.7 55 915 12 2.1 -- MHz dBm V %
2nd to 13th Harmonics Output Power
2f0 to 13f0 POUT
-- 34.5
-- 35.0
-7 --
dBm dBm
POUT MAX
32
33
--
dBm
POUT MAX
32
33
--
dBm
Input VSWR Forward Isolation
IN POUT STANDBY
-- --
1.5:1 -35
2:1 -30
-- dBm
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Electrical Specifications
CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Table 3. CX77301 Electrical Specifications (2 of 4)(1) Parameter
Switching Time
Symbol
RISE, FALL
Test Condition
Time from POUT = -10 dBm to POUT = +5 dBm, 90% Time from POUT = -10 dBm to POUT = +20 dBm, 90% Time from POUT = -10 dBm to POUT = +34.5 dBm, 90%
Min
-- -- --
Typical
5 5 2
Max
8 8 4
Units
s s s
Spurious
Spur
All combinations of the following parameters: VAPC = controlled(2) PIN = min. to max. VCC = 2.9 V to 4.8 V Load VSWR = 8:1, all phase angles All combinations of the following parameters: VAPC = Controlled(2) PIN = Min. to Max. VCC = 2.9 V to 4.8 V Load VSWR = 10:1, all phase angles At f0 + 20 MHz: RBW = 100 kHz VCC = 3.5 V 5 dBm POUT 34.5 dBm At f0 + 10 MHz: RBW = 100 kHz VCC = 3.5 V 5 dBm POUT 34.5 dBm At 1805 to 1880 MHz: RBW = 100 kHz VCC = 3.5 V 5 dBm POUT 34.5 dBm --
No parasitic oscillation > -36 dBm
Load Mismatch
No module damage or permanent degradation
Load
Noise Power
--
-82
dBm
--
--
-76
dBm
PNOISE
--
--
-90
dBm
Coupling of 2nd and 3rd Harmonic from the EGSM Band into the DCS Band
2f0, 3f0
Measured at the DCS output, -15 dBm POUT 34 dBm
--
-25
-20
dBm
DCS Mode (f = 1710 to 1785 MHz and PIN = 5 to 11 dBm)
Frequency Range Input Power Analog Power Control Voltage Power Added Efficiency f PIN VAPC PAE POUT = 29.5 dBm VCC = 3.5 V POUT 31.5 dBm VAPC 2.0 V, pulse width = 577 s, duty cycle = 1:8 TCASE = +25 C -- -- 1710 5 1.35 45 -- -- 1.7 50 1785 11 2.1 -- MHz dBm V %
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CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Table 3. CX77301 Electrical Specifications (3 of 4)(1) Parameter
2nd to 7th Harmonics Output Power
Electrical Specifications
Symbol
2f0 to 7f0 POUT
Test Condition
BW = 3 MHz 0 dBm POUT 32 dBm VCC = 3.5 V VAPC 2.0 V TCASE = +25 C VCC = 2.9 V VAPC 2.6 V TCASE = -20 C to +100 C (See Table 2 for multi-slot) PIN = 5 dBm VCC = 4.8 V VAPC 2.6 V TCASE = -20 C to +100 C (See Table 2 for multi-slot) PIN = 5 dBm POUT = 0 to 32 dBm, controlled by VAPC PIN = 10.5 dBm VAPC = 0.3 V Time from POUT = -10 dBm to POUT = 0 dBm, 90%
Min
-- 31.5
Typical
-- 32.0
Max
-7 --
Units
dBm dBm
POUT MAX
29.5
30.5
--
dBm
POUT MAX
29.5
30.5
--
dBm
Input VSWR Forward Isolation
IN POUT STANDBY
-- --
-- -40
2:1 -35
-- dBm s s s
Switching Time
-- -- --
10 5 2
12 8 5
RISE, FALL
Time from POUT = -10 dBm to POUT = +20 dBm, 90% Time from POUT = -10 dBm to POUT = +31.5 dBm, 90%
Spurious
Spur
All combinations of the following parameters: VAPC = Controlled(3) PIN = min. to max. VCC = 2.9 V to 4.8 V Load VSWR = 8:1, all phase angles
No parasitic oscillation > -36 dBm
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Electrical Specifications
CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Table 3. CX77301 Electrical Specifications (4 of 4)(1) Parameter
Load Mismatch
Symbol
Test Condition
All combinations of the following parameters: VAPC = Controlled(3) PIN = Min. to Max. VCC = 2.9 V to 4.8 V Load VSWR = 10:1, all phase angles At f0 + 20 MHz: RBW = 100 kHz VCC = 3.5 V 0 dBm POUT 31.5 dBm At 925 to 960 MHz: RBW = 100 kHz VCC = 3.5 V 0 dBm POUT 31.5 dBm
Min
Typical
Max
Units
No module damage or permanent degradation
Load
Noise Power
--
--
-80
dBm
PNOISE
--
--
-95
dBm
NOTE(S):
(1) (2) (3)
Unless specified otherwise: TCASE = -20 C to maximum operating temperature (see Table 2), RL = 50 , pulsed operation with pulse width 2308 s, duty cycle 4:8, VCC = 2.9 V to 4.8 V IC = 0A to xA, where x = current at POUT = 34.5 dBm, 50 load, and VCC = 3.5 V. lC = 0A to xA, where x = current at POUT = 32.0 dBm, 50 load, and VCC = 3.5 V.
Figure 1. Typical CX77301 Application
Note 2 APC from PAC Note 2
BS in from Baseband
APC in 14
16
10 pF
DCS / PCS in 2
DCS / PCS out 12
10 pF
CX77301
EGSM in 4 EGSM out 10
33 pF
6 Vcc1 drivers
8 Vcc2 output stages
V bat
100 pF Note 1 Note 1 - Should be very close to PA module Note 2 - Optional depending on PAC circuit
10 nF Note 1
10 uF tantalum
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CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Package Dimensions and Pin Descriptions
Package Dimensions and Pin Descriptions
Figure 2 displays the dimensions of the 16-pin leadless CX77301 dual-band PAM. Figure 3 shows the device pin configuration, and Table 4 describes the pin names.
Figure 2. CX77301 PAM Package Dimensions-16-pin Module (All Views)
R0.381 Typ 0.762 Typ R0.860 Typ 0.127 Ref
Pin 1
2.286 0.051
9.10 +0.20, -0.08
1.905 0.051 2.286 0.051
11.60 +0.20, -0.08 TOP VIEW
0.737 0.051 3.899 0.051
1.905 0.051 BOTTOM VIEW
1.02 Typ
1.50 max. FRONT VIEW
NOTE(S): 1. All contact points are gold plated, lead-free surfaces. 2. All dimensions are in millimeters.
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Package Dimensions and Pin Descriptions
CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Figure 3. CX77301 Package and Pin Configuration (Top view)
BS
GND
APC
GND
1
16
15
14 13 GND
DCS IN
2
12
DCS OUT
GND
3
11
GND
EGSMIN
4
10
EGSM OUT
GND
5
6
7
8
9
GND
VCC1
GND
VCC2
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Table 4. CX77301 Signal Description Pin
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 GND DCS IN GND EGSM IN GND VCC GND VCC GND EGSM OUT GND DCS OUT GND APC GND BS
Name
Ground
Description
RF input to DCS PA (DC coupled) Ground RF input to EGSM PA Ground Power supply for PA driver stages Ground Power supply for PA output stages Ground EGSM RF output (DC coupled) Ground DCS RF output (DC coupled) Ground Analog Power Control Ground Band select
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Conexant
100956D Jannuary 2, 2002
CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Package and Handling Information
Package and Handling Information
Production quantities of this product are shipped in the standard tape and reel format illustrated in Figure 4 below.
Figure 4. CX77301 Tape and Reel Dimensions
12.00 0.10
4.00 0.10
1.50 0.10 2.00 0.10 1.75 0.10
11.50 0.10
1.50 0.25 Pin #1 indicator
0.330 0.013
8o Max 2.02 0.10 9.40 0.10 11.90 0.10
5o Max
A0
K0 3M Carrier Tape
B0
NOTE(S): 1. Carrier tape material: Conductive polycarbonate 2. Carrier tape part number: US 042 281 3. Cover tape material: Conductive Pressure Sensitive Adhesive (PSA) 4. Cover tape size: 21.3 mm wide 5. Number of parts per 13 inch x 24 mm reel: 2000 6. All diagram dimensions in mm
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Conexant
24.00 +0.30/-0.10
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Electrostatic Discharge Sensitivity
CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Electrostatic Discharge Sensitivity
The CX77301 is a Class I device. Figure 5 lists the Electrostatic Discharge (ESD) immunity level for each pin of the CX77301 product. The numbers in Figure 5 specify the ESD threshold level for each pin where the I-V curve between the pin and ground starts to show degradation. The ESD testing was performed in compliance with MIL-STD-883E Method 3015.7 using the Human Body Model. Since 2000 volts represents the maximum measurement limit of the test equipment used, pins marked > 2000 V pass 2000 V ESD stress.
Figure 5. ESD Sensitivity Areas (Top view)
> +2000 V < -2000 V BS > +2000 V < -2000 V APC
GND 8
16 GND 1 1
15
14 13 GND 7
> +2000 V DCS IN < -2000 V
2
12
DCS OUT
> +2000 V < -2000 V
GND 2
3
CX77301
11
GND 6
+450 V EGSM IN -500 V
4
10
> +2000 V EGSM OUT < -2000 V
GND 3
5
6
7
8
9
GND 5
VCC1 > +2000 V < -2000 V
GND 4
VCC2 > +2000 V < -2000 V
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Various failure criteria can be utilized when performing ESD testing. Many vendors employ relaxed ESD failure standards which fail devices only after "the pin fails the electrical specification limits" or "the pin becomes completely non-functional". Conexant employs most stringent criteria, fails devices as soon as the pin begins to show any degradation on a curve tracer. To avoid ESD damage, both latent or visible, it is very important that the product assembly and test areas follow the Class-1 ESD handling precautions listed in Table 5.
Table 5. Precautions for GaAs ICs with ESD Thresholds Greater Than 200 V But Less Than 2000 V
Personnel Grounding Wrist Straps Conductive Smocks, Gloves and Finger Cots Antistatic ID Badges Protective Workstation Dissipative Table Tops Protective Test Equipment (Properly Grounded) Grounded Tip Soldering Irons Conductive Solder Suckers Static Sensors Facility Relative Humidity Control and Air Ionizers Dissipative Floors (less than 109 to GND) Protective Packaging & Transportation Bags and Pouches (Faraday Shield) Protective Tote Boxes (Conductive Static Shielding) Protective Trays Grounded Carts Protective Work Order Holders
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CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Technical Information
Technical Information
CMOS Bias Controller Characteristics
The CMOS die within the PAM performs several functions that are important to the overall module performance. Some of these functions must be considered for development of the power ramping features in a 3GPP compliant transmitter power control loop1. Power ramping considerations will be discussed later in this section. The four main functions that will be described in this section are Standby Mode Control, Band Select, Voltage Clamp, and Current Buffer. The functional block diagram is shown in Figure 6.
Figure 6. Functional Block Diagram
Band Select (pin16)
vodcs
CComp
APC input (pin14)
Supply (pin6)
cpgsm
CComp
cpdcs
vogsm
Combinational Logic Voltage Clamp
Bandgap Reference
CMOS bias controller
DCS1800 bias out ground GSM900 bias out
Cbypass
RF Isolation
Cbypass
RF Isolation
Dual Band GaAs Power Amplifier Die
100956_01
1.
Please refer to 3GPP TS 05.05, Digital Cellular Communications System (Phase 2+); Radio Transmission and Reception. All GSM specifications are now the responsibility of 3GPP. The standards are available at http://www.3GPP.org/3G_specs/spec_titles.htm
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Technical Information
CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Standby Mode Control
The Combinational Logic cell includes enable circuitry that monitors the APC ramping voltage from the power amplifier controller (PAC) circuit in the GSM transmitter. Typical handset designs directly connect the PA VCC to the battery at all times, and for some PA manufacturers this requires a control signal to set the device in or out of standby mode. The Conexant PAM does not require a Transmit Enable input because it contains a standby detection circuit that senses the VAPC to enable or disable the PA. This feature helps minimize battery discharge when the PA is in standby mode. When VAPC is below the enable threshold voltage, the PA goes into a standby mode, which reduces battery current (ICC) to 6 A, typical, under nominal conditions. For voltages less than 700 mV at the APC input (pin 14), the PA bias is held at ground. As the APC input exceeds the enable threshold, the bias will activate. After an 8 s delay, the amplifier internal bias will ramp quickly to match the ramp voltage applied to the APC input. In order for the internal bias to precisely follow the APC ramping voltage, it is critical that a ramp pedestal is set to the APC input at or above the enable threshold level with a timing at least 8 s prior to ramp-up. This will be discussed in more detail in the following section, "Power Ramping Considerations for 3GPP Compliance".
Band Select
The Combinational Logic cell also includes a simple gate arrangement that selects the desired operational band by activating the appropriate current buffer. The voltage threshold level at the Band Select input (pin 16) will determine the active path of the bias output to the GaAs die.
Voltage Clamp
The Voltage Clamp circuit will limit the maximum bias voltage output applied to the bases of the HBT devices on the GaAs die. This provides protection against electrical overstress (EOS) of the active devices during high voltage and/or load mismatch conditions. Figure 7 shows the typical transfer function of the APC input to buffer output under resistively loaded conditions. Notice the enable function near 600 mV, and the clamp acting at 2.15 V, corresponding to a supply voltage of 4.0 V.
Figure 7. Base Bias Voltage vs. APC Input, VCC = 4.0 V
2.5
2 Base Bias (volts)
1.5 clam p 1
0.5
0 0 0.5 1 1.5 APC input (volts) 2 2.5 3
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CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Technical Information
Due to output impedance effects, the bias of the GaAs devices increases as the supply voltage increases. The Voltage Clamp is designed to gradually decrease in level as the battery voltage increases. The performance of the clamp circuit is enhanced by the band gap reference that provides a supply-, process-, and temperature-independent reference voltage. The transfer function relative to VBAT is shown in Figure 8. For battery voltages below 3.4 V, the base bias voltage is limited by the common mode range of the buffer amplifier. For battery voltages above 3.4 V, the clamp limits the base bias.
Figure 8. Base Bias Clamp Voltage vs. Supply Voltage
2.6 2.5 clam p 2.4
Base Bias Clamp (Volts)
2.3 2.2 2.1 2 1.9 1.8 1.7 3 3.25 3.5 3.75 4 4.25 4.5
Vcc (Volts)
Current Buffer
The output buffer amplifier performs a vital function in the CMOS device by transferring the APC input voltage ramp to the base of the GaAs power devices. This allows the APC input to be a high impedance port, sinking only 10 A, typical, assuring no loading effects on the PAC circuit. The buffers are designed to source the high GaAs base currents required, while allowing a settling time of less than 8 s for a 1.5 V ramp.
Power Ramping Considerations for 3GPP Compliance
These are the primary variables in the power control loop that the system designer must control: * * * * * software control of the DSP / DAC software control of the transmitter timing signals ramp profile attributes - pedestal, number of steps, duration of steps layout of circuit / parasitics RC time constants within the PAC circuit design
All of these variables will directly influence the ability of a GSM transmitter power control loop to comply with 3GPP specifications. Although there is a specific time mask template in which the transmitter power is allowed to ramp up, the method is very critical. The 3GPP system specification for switching transients results in a
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Technical Information
CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
requirement to limit the edge rate of output power transitions of the mobile. Switching transients are caused by the transition from minimum output power to the desired output power, and vice versa. The spectrum generated by this transition is due to the ramping waveform amplitude modulation imposed on the carrier. Sharper transitions tend to produce more spectral "splatter" than smooth transitions. If the transmit output power is ramped up too slowly, the radio will violate the time mask specification. In this condition, the radio may not successfully initiate or maintain a phone call. If the transmit output power is ramped up too quickly, this will cause RF "splatter" at certain frequency offsets from the carrier as dictated by the 3GPP specification. This splatter, known as Output RF Spectrum (ORFS) due to Switching Transients, will increase the system noise level, which may knock out other users on the system. The main difficulty with TDMA power control is allowing the transmitter to ramp the output power up and down gradually so switching transients are not compromised while meeting the time mask template at all output power levels in all operational bands. The transmitter has 28 s to ramp up power from an off state to the desired power level. The GSM transmitter power control loop generally involves feedback around the GaAs PA, which limits the bandwidth of signals that can be applied to the PA bias input. Since the PA is within the feedback loop, its own small-signal frequency response must exhibit a bandwidth 5 to 10 times that of the power control loop. As discussed in the previous section, the PA bias is held at ground for inputs less than 700mV. As the APC input exceeds the enable threshold, the bias will activate. After an 8 s delay, the amplifier internal bias will quickly ramp to match the ramp voltage applied to the VAPC input. Since the bias must be wide band relative to the power control loop, the ramp will exhibit a fast edge rate. If the APC input increases beyond 1V before the 8 s switching delay is allowed to occur after the bias is enabled, the PA will have significant RF output as the internal bias approaches the applied bias. During this ramp, the internal power control is running "open loop" and the edge rates are defined by the frequency response of the PA bias rather than that of the power control loop. This open loop condition will result in switching transients that are directly correlated to the PA bias bandwidth. Application of an initial APC voltage, which enables the bias at least 8 s before the VAPC voltage is ramped, will ensure that the internal bias of the PAM will directly follow the applied VAPC. As a result, the power control loop will define all edge transitions rather than the PA internal bandwidth defining the transition. Figures 9 and 10 show the relationship of the internal bias relative to the applied APC in two cases. One case has ramping starting from ground; the other case has ramping starting with an initial enable pedestal of 700 mV It is evident that the pedestal level is critical to . ensure a predictable and well behaved power control loop. To enable the CMOS driver in the PAM prior to ramp-up, a PAC output pedestal level to the APC input of the PAM (pin 14) should be set to about 700 mV. This pedestal level should have a duration of at least 8 s directly prior to the start of ramp up. Figure 11 shows typical signals and timings measured in a GSM transmitter power control loop. This particular example is at GSM Power Level 5, Channel 62. The oscilloscope traces are TxVCO_enable, PAC_enable, DAC Ramp, and VAPC (pin 14).
NOTE:
When the TxVCO is enabled, the pedestal becomes set at the APC input of the PAM, then the PAC is enabled, and finally the DAC ramp begins.
The device specifications for enable threshold level and switching delay are shown in Table 3.
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CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Figure 9. PAM Internal Bias Performance - No Pedestal Applied
Technical Information
1.6 1.4 1.2
Bias Voltage (V)
Vapc In (V) Internal bias (V)
1 0.8 0.6 0.4 0.2 0 0 5 10 15 20 25 30 35
Time (sec)
Figure 10. PAM Internal Bias Performance - Pedestal Applied
1.6 1.4 1.2
Bias Voltage (V)
Vapc In (V) Internal Bias (V)
1 0.8 0.6 0.4 0.2 0 0 5 10 15 20 25 30 35
Time (sec)
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Technical Information
CX77301
PA Module for Dual-band EGSM900 / DCS1800 / GPRS
Figure 11. GSM Transmitter - Typical Ramp-up Signals
T
1
DAC Ramp
2
TxVCO_enable
PAC_enable 3 VAPC 4 Ch1 Ch3 200 mV 1.00 V Ch2 Ch4
VAPC Pedestal
1.00 V 500 mV
BW M
10.0 s
A
Ch2
500 mV
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100956D Jannuary 2, 2002
Ordering Information
Model Number CX77301 Manufacturing Part Number CX77301 Product Revision -13 Package 9.1 x 11.6 x 1.5 mm Operating Temperature -20 C to +100 C
Revision History
Revision A B C D Level Date June 2000 January 2001 March 2001 January 2, 2002 Initial Release New Tables 3,4; revise Figure 4. Add ESD data, revised format to add chapter headings Add: Technical Information Section Revise: Functional Block Diagram; Figure 10; ESD data (+/- thresholds) Description
References:
Application Note: PCB Design and SMT Assembly/Rework, Document Number 101762A
(c) 2001, Conexant Systems, Inc.
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