PBM 990 80
PBM 990 80 together with a Bluetooth radio and the
firmware, forms a Bluetooth radio link.
Functional description
Overview
Ericsson Bluetooth Core (EBC)
The purpose of this section is to give a brief description of
the features and functions in the PBM 990 80 product and
how it can work in a system. PBM 990 80 is a two-chip
stacked die solution, packaged into a 78 pin LGA/BGA
package, see Mechanical description for further information.
EBC is the name of the Bluetooth dedicated hardware
designed to offload the processor by taking care of heavy
calculation tasks such as whitening, CRC check, ciphering
of data, forward error correction and Bluetooth packet
segmentation & reassemble. EBC is compliant with the
Bluetooth specification revision 1.1 and includes the
following key features:
PBM 990 80 handles the baseband functionality in a
Bluetooth radio link, i.e. the digital controller logic. The
baseband functionality is partitioned in one hardware and
one software part. The software part is executed by an
on-chip microprocessor ARM7TDMI. To increase the ease
of use, standard interfaces like USB 2.0 Full-speed, UARTs,
PCM and Bidirectional serial interface/GPIO are integrated
on the baseband chip.
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ACL link support giving data rates up to 721 kbit/s over
the air interface.
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SCO link with support for upto three voice channels over
the air interface.
PBM 990 80 philosophy is to provide a scalable solution
with a high level of flexibility. The goal is to offer a solution
that can be easily added to an existing system to enable
Bluetooth capabilities, or to provide the means for an
embedded stand-alone Bluetooth application. The solution
offers designers:
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•
•
•
•
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HW support for all packet types.
Support for one PCM-channel.
Architecture designed for low power consumption.
HOLD, SNIFF, PARK modes
Ciphering keys up to 128 bits
•
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Power versus performance trade-offs
High quality filtering of voice packets enables excellent
voice quality.
Reduced need for external components (oscillators, USB
PHY transceiver etc)
•
Flexible voice formats to host and over air (CVSD, PCM,
16/8 bit 1st and 2nd complement, signed, a-law, µ-law).
To save power, all interfaces can individually be turned
off and the processor speed can be adapted to produce a
suitable capacity, depending on what application is running.
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Point to multipoint with support for up to 7 slaves.
Master/Slave switch capability
The radio part requires a crystal or a clock frequency with
±20 ppm accuracy. The PMB 990 80 is designed to be
flexible in this matter and can re-use a square or sine wave
clock signal for a wide spectrum of frequencies depending
on the kind of reference signal used by the radio.
Radio interface is compliant with BlueRF interface V0.9,
Unidirectional mode, RXMODE2.
Host interfaces
Architecture
To enable a host system to access the Bluetooth radio link,
a Host Controller Interface (HCI) has been defined. The
host system controls and distributes data to and from the
Bluetooth Link Manager with a set of commands. These
commands are carried physically on either the USB or UART
interface.
The Bluetooth functionality is based on both hardware and
software, forming an embedded system design targeting
both flexibility and scalability. The system architecture is
based around an ARM7TDMI processor, executing the
Bluetooth stack drivers, and a Hardware block: Ericsson
Bluetooth Core, supporting Bluetooth Standard 1.1. The
supported interfaces: USB 2.0 Full-speed and UARTs are
used to access the chip from a host system.
USB
Host I/F
UART1
Flash
UART2
GPIO
ARM7
Bluetooth
Base Band Chip
GPIO
TDMI
Radio
Ericsson
Debug&
PBM 990 80
External
Test I/F
Test
Blue RF I/F
PBA 313 01
PBA 313 02
PBA 313 05
Bus
Interface
Interface
Others
64kB
ROM
SRAM
Bluetooth
Radio
PBA 313 01
PBA 313 02
PBA 313 05
Host
System
Ericsson
Bluetooth
Core
HCI
PCM
PCM
Codec
Blue RFI/F
UART (max 921 kb/s)
USB 2.0 (12 Mb/s)
Figure 6. Example system using the Ericsson
Microelectronics PBM 990 80 baseband.
Figure 7. Bluetooth architecture.
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ERICSSON [ ERICSSON ]
