CSR1001A04-IQQA-R Datasheet, PDF (18/45 Pages) –

2 Bluetooth Modem
2.1 RF Ports
CSR1001 QFN contains an integrated balun which provides a single-ended RF TX / RX port pin. No matching
components are needed as the receive mode impedance is 50Ω and the transmitter has been optimised to deliver
power in to a 50Ω load.
2.2 RF Receiver
The receiver features a near-zero IF architecture that allows the channel filters to be integrated onto the die. Sufficient
out-of-band blocking specification at the LNA input allows the receiver to be used in close proximity to GSM and
W‑CDMA cellular phone transmitters without being significantly desensitised.
An ADC digitises the IF received signal.
2.2.1 Low Noise Amplifier
The LNA operates in differential mode and takes its input from the balanced port of the integrated balun.
2.2.2 RSSI Analogue to Digital Converter
The ADC samples the RSSI voltage on a packet-by-packet basis and implements a fast AGC. The front-end LNA
gain is changed according to the measured RSSI value, keeping the first mixer input signal within a limited range.
This improves the dynamic range of the receiver, improving performance in interference-limited environments.
2.3 RF Transmitter
2.3.1 IQ Modulator
The transmitter features a direct IQ modulator to minimise frequency drift during a transmit packet, which results in
a controlled modulation index. Digital baseband transmit circuitry provides the required spectral shaping.
2.3.2 Power Amplifier
The internal PA has a maximum 7.5dBm output power without needing an external RF PA.
2.4 Bluetooth Radio Synthesiser
The Bluetooth radio synthesiser is fully integrated onto the die with no requirement for an external VCO screening
can, varactor tuning diodes, LC resonators or loop filter. The synthesiser is guaranteed to lock in sufficient time
across the guaranteed temperature range to meet the Bluetooth v4.0 specification.
2.5 Baseband
2.5.1 Physical Layer Hardware Engine
Dedicated logic performs:
■ _{Cyclic redundancy check}
■ _Encryption
■ Data whitening
■ _{Access code correlation}
The hardware supports all optional and mandatory features of Bluetooth v4.0 specification.
Production Information
© Cambridge Silicon Radio Limited 2011-2013
Page 17 of 44
CS-216358-DSP5
www.csr.com