AMIS-50051: Digital Demodulator Data Shee
t
Wireless Products
1.0 Introduction
The AMIS-50051 is a small digital demodulator, specially developed to work with the AMIS-50050 spread spectrum baseband
controller. It simplifies the design of the receiver in a direct sequence spread spectrum wireless communication link.
2.0 Key Features
• 1Mbit/s demodulation (QPSK)
• PN code tracking output to AMIS-50050 (Please refer to the AMIS-50050 spread spectrum baseband controller.)
• Fully programmable
• CMOS technology
• Power-down mode
3.0 Applications
• Wireless local area networks
• Portable wireless communication
• Digital cellular telephones
• Wireless ISDN modems
The AMIS-50051 simplifies the design of the receiver in a direct sequence spread spectrum wireless communication link. The AMIS-
50051 uses advanced DSP technology to demodulate the data from a BPSK/DBPSK/QPSK/DQPSK modulated signal. This technique
also provides a PN code tracking signal output, a carrier tracking signal and an automatic gain control (AGC) output signal. The power
of the AMIS-50051 reduces the complexity and component count of a DSSS receiver. The AMIS-50051 is designed to demodulate
QPSK or BPSK data from a carrier whose frequency is11MHz or less. Data rates can be as high as 1Mbit/s for QPSK signals or
500Kbit/s for BPSK signals. An error signal is produced, which can be used to acquire and track the PN code of a direct sequence
spread spectrum system. This output is a voltage, which the AMIS-50050 (please refer to AMIS-50050 spread spectrum baseband
controller) uses to change the phase of the receiver’s PN code. An external despreading device is required to remove the PN code from
the received signal. This reduces the chance of false acquisition over other methods. The AMIS-50051’s internal NCO oscillator is
adjusted by a signal produced from the data demodulation process. This is used to track variations in the carrier frequency of the
received signal.
The AMIS-50051 produces a level error output. This output is pulsed high or low depending on the level of the received signal. This can
be used to form an AGC circuit.
The AMIS-50051 requires few external components. The AMIS-50051 is designed to work directly with the AMIS-50050 to simplify the
design effort of a wireless communication link.
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AMIS-50051: Digital Demodulator Data Shee
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4.0 AMIS-50051 Block Diagram
Figure 1: Block Diagram of AMIS-50051
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AMIS-50051: Digital Demodulator Data Shee
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5.0 Package Availability
• 24 pin SOIC
• 32 pin TQFP
Figure 2: Package Availability
Table 1: Pin Descriptions
Pin Name Number on
24 Pin SOIC
Number on
32 Pin
TQFP Functional Desc ription Type
DVDD 1,12 11, 30 Digital power Power
DVSS 2,11 10, 31 Digital ground Ground
SDATA 3 32, Data for serial programming interface Input
SCLK 4 1 Clock for serial programming interface, sensitive to rising edge Output
RSSI2 5 2 RSSI 2 for AMIS-50050 Output
RSSI1 6 3 RSSI 1 for AMIS-50050 Output
RXD0 7 6 Received data Bit 0 Output
RXD1 8 7 Received data Bit 1 Output
TRACKON 9 8 Indicates that the AMIS-50050 is tracking the incoming signal, active high Input
DUMP 10 9 Activate and dump control logic input Input
LPF 15 16 PLL phase detector output, internal VCO output Analog
CRYST1 16 17 Crystal oscillator or external reference input Crystal OSC/Input
CRYST0 17 18 Crystal oscillator Crystal OSC
EXT_IN 18 19 Used as digital input from external window comparator, test input not for
normal use Input
RES 19 22 Active low reset Input
AGC 20 23 Automatic gain control Output
RX_IN 21 24 IF signal input, can also be used as digital input from external window
comparator Analog/Input
ENABLE 24 27 Active low enable for serial programming interface Input
AVDD 13,23 26 Analog power Power
AVSS 14,22 25 Analog ground Ground
NC
4, 5, 12, 13,
20, 21, 28,
29
Not connected
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AMIS-50051: Digital Demodulator Data Shee
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Wireless Products
6.0 Electrical Specifications
6.1 Absolute Maximum Ratings
Table 2: Absolute Maximum Ratings
Parameter Min. Max. Units
VDD/AVDD -0.3 5.5 V
Input pin voltage, all pins -0.3 VDD+0.3 V
Input pin current, all pins -10 10 mA
Storage temperature -55 125 oC
Lead temperature 300 oC for 10 seconds
Note: Stresses beyond those listed under “Absolute Maximum Ratings” may cause damage to the device. This is a stress rating only and functional operation of the device at
these, or any other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for
extended periods may affect device reliability.
6.2 Operational Characteristics
Table 3: Operational Characteristics
Symbol Parameter Min. Typ. Max. Units
VDD Supply voltage 3 5 V
ICC Supply current (5V) 18 mA
ICC Supply current (3V) 8 mA
IFI IF frequency (1) 11 MHz
IFE IF frequency
(2) 25 MHz
RXiv Input voltage 200 300 mVpp
RXii Input impedance
(3) 100 kΩ
Fref Reference frequency 2 MHz
Rsol RSSI 1&2 output level 0 2.5 V
Srte Internal sample rate 1.56 100 MHz
Notes:
(1) Using the internal A to D converter
(2) Using an external A to D converter
(3) Impedance for only the RXin pin
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AMIS-50051: Digital Demodulator Data Shee
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6.3 Supply Current for 5V Operation
Figure 3: Supply Current for 5V Operation
Note: The frequency in MHz is the frequency of the internal clock, Fvco.
6.4 Supply Current for 3V Operation
Figure 4: Supply Current for 3V Operation
Note: The frequency in MHz is the frequency of the internal clock, Fvco.
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AMIS-50051: Digital Demodulator Data Shee
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Wireless Products
6.5 AMIS-50051 Programming In terface
The AMIS-50051 uses a 3-wire interface, enable/clock and data. The enable is active low.
Figure 5: Active Enable Mode Timing
Table 4: Active Enable Timing Specifications
Parameter Typical Slow Mode Typical Fast Mode Units
tLE 16 0.500 µsec
tH12 0.125 µsec
tSU 4 0.125 µsec
tPULSE 8 0.250 µsec
tLEH 8 0.250 µsec
Note: The AMIS-50051 uses the three wire serial interface for programming. The protocol used is the “Active Enable” mode with a slow clock and enable active low.
6.6 Typical AMIS-50050 to AMIS-50051 Code
It is recommended to program the AMIS-50051 via the AMIS-50050. AMIS applications notes to support customer programming are
available.
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AMIS-50051: Digital Demodulator Data Shee
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Wireless Products
7.0 AMIS-50051 Ordering Codes
Table 5: Ordering Codes
Device Number Package
11564-502-XTP (or –XTD) 24 Lead SOIC
11564-503-XTP (or –XTD) 32 Lead LQFP
11564-504-XTP (or –XTD) 32 Lead LQFP
(green/RoHS)
Note: XTP – tape and reel. XTD – tube/tray
8.0 Company or Product Inquiries
For more information about AMI Semiconductor, our technology and our product, visit our Web site at: http://www.amis.com.
North America
Tel: +1.208.233.4690
Fax: +1.208.234.6795
Europe
Tel: +32 (0) 55.33.22.11
Fax: +32 (0) 55.31.81.12
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Devices sold by AMIS are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. AMIS makes no warranty, express,
statutory, implied or by description, regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. AMIS makes
no warranty of merchantability or fitness for any purposes. AMIS reserves the right to discontinue production and change specifications and prices at any time and
without notice. AMI Semiconductor's products are intended for use in commercial applications. Applications requiring extended temperature range, unusual
environmental requirements, or high reliability applications, such as military, medical life-support or life-sustaining equipment, are specifically not recommended without
additional processing by AMIS for such applications. Copyright ©2006 AMI Semiconductor, Inc.
