User's Manual
Table Of Contents
- General Description
- Features
- System Applications
- Block Diagram
- Pin Assignments
- Pin Descriptions
- CPU Access to Endpoint Data
- USB Request
- Get Descriptor-Device
- Get Descriptor-Device Qualifier (High Speed)
- Get Descriptor-Configuration
- Get Descriptor-String Index 0
- Get Descriptor-String Index 1
- Get Descriptor-String Index 2
- Get Descriptor-String Index 3
- Get Descriptor-String Index 4
- Get Descriptor-String Index 5
- Get Descriptor-Other Speed Configuration
- Set Address
- Set Interface 0
- Set Feature Device
- Clear Feature Device
- Set Config 0
- Set Config 1
- EEPROM (93C46 or 93C56) Contents
- USB Packet Buffering
- Functional Description
- Application Diagram
- Electrical Characteristics
- Mechanical Dimensions
- Ordering Information
RTL8187L
Datasheet
Wireless LAN Network Interface Controller 1 Track ID JATR-1076-21 Rev. 1.2
1. General Description
The Realtek RTL8187L is a low-profile highly integrated cost-effective Wireless LAN USB 2.0 network
interface controller that integrates a USB 2.0 PHY, SIE (Serial Interface Engine), 8051 MCU, a Wireless
LAN MAC, and a Direct Sequence Spread Spectrum/OFDM baseband processor onto one chip. It provides
USB high speed (480Mbps), and full speed (12Mbps), and supports 4 endpoints for transfer pipes. To
reduce protocol overhead, the RTL8187L supports Short InterFrame Space (SIFS) burst mode to send
packets back-to-back. A protection mechanism prevents collisions among 802.11b nodes. The RTL8187L
fully complies with IEEE 802.11a/b/g specifications.
Direct Sequence Spread Spectrum (DSSS), Complementary Code Keying (CCK), and Orthogonal
Frequency Division Multiplexing (OFDM) baseband processing are implemented to support all IEEE
802.11a, 802.11b, and 802.11g data rates. Differential phase shift keying modulation schemes, DBPSK and
DQPSK with data scrambling capability, are available, along with complementary code keying to provide
data rates of 1, 2, 5.5, and 11Mbps, with long or short preamble. A high-speed Fast Fourier Transform
(FFT)/Inverse Fast Fourier Transform (IFFT), combined with BPSK, QPSK, 16QAM and 64QAM
modulation of the individual sub-carriers, provides data rates of 6, 9, 12, 18, 24, 36, 48 and 54Mbps, with
rate-compatible punctured convolutional coding with a coding rate of 1/2, 2/3, and 3/4.
An enhanced signal detector, an adaptive frequency domain equalizer, and a soft-decision Viterbi decoder
are built-in to alleviate severe multipath effects. Efficient IQ-imbalance calibration, DC offset, phase noise,
frequency offset, and timing offset compensation reduce radio frequency front-end impairments. Selectable
digital transmit and receiver FIR filters are provided to meet the requirements of transmit spectrum masks,
and to reject adjacent channel interference, respectively. Both in the transmitter and receiver,
programmable scaling in the digital domain trades the quantization noise against the increased probability
of clipping. Robust signal detection, symbol boundary detection, and channel estimation perform well at
the minimum sensitivity.
The RTL8187L supports fast receiver Automatic Gain Control (AGC) and antenna diversity functions, and
an adaptive transmit power control function to obtain better performance in the analog portions of the
transceiver. It also has on-chip digital-to-analog converters and analog-to-digital converters for analog I
and Q inputs and outputs, transmit TSSI and receiver RSSI inputs, and transmit and receiver AGC outputs.
The RTL8187L is highly integrated and requires no ‘glue’ logic or external memory. It keeps network
maintenance costs low and eliminates usage barriers.