RF6001_1 RFMD [RF Micro Devices], RF6001_1 Datasheet - Page 27

• Manufacturer Part Number: RF6001_1
• Description: FRACTIONAL-N RF SYNTHESIZER WITH MODULATOR AND DIGITAL IF FILTER
• Manufacturer: RFMD [RF Micro Devices]

As initial guidance for the settings of the DC offset and blanking system, the following two setups are presented. Both are
acceptable for GPRS operation. The 160usec option represents a minimum startup time. The 210usec startup option will min-
imize any DC errors due to initial thermal drift.
Transmit Information
Transmit Turn-On Sequence
The following diagram documents the transmit turn-on sequence when using the RF6001 with the RF3146 power amplifier.
The sequence is initiated by taking TXST signal high. The RF6001 requires 140μs worst case for all calibrations and PLL lock to
take place. Once this is complete, the PA will be turned on by taking TXEN high (TXENU=140μs). The PA ramp should start
about 2μs later for optimal switching spectrum performance of the RF3146 (PAT=142μs).
There is a programming feature within the RF6001 to provide real-time control of the front-end transmit/receive (T/R) switch.
The T/R switch must be turned off during the prior bust to ensure the ETSI time-mask is not violated. This feature is invoked by
setting TRD bit high. The GPO1, GPO2 and GPO3 outputs of the RF6001 will be set to values programmed into TRDC_TX(2:0)
bits when TXST is taken high. These values should turn off the T/R switch for the given transmit state. After time TXENU, the
GPO outputs of the RF6001 will revert back to the originally programmed states defined in SDI bits GPO1, GPO2 and GPO3.
Rev A3 DS050929
160usec Startup
DCTIME1=20us
BLK_DLY=1fh=114.5us
210usec Startup
DCTIME1=20us
BLK_DLY=2ch=162.5us
PA Ramp
RF6001
RF6001
Turn on
TXEN
TXST
GPO
pins
GPO3
GPO2
GPO1
Activate RF6001
DCTIME2=140us
AGC_DLY=2ch=162.5us
DCTIME2=180us
AGC_DLY=39h=210.5us
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support, contact RFMD at ([phone] or [e-mail].
t=-155usec
t=-140usec
PA DAC
Turn on
TRDC_TX(2)
TRDC_TX(1)
TRDC_TX(0)
140us startup time
TXENU
DCAD=23h=129.2us
DCAD_2=25h=136.6us
DCAD=30h=177us
DCAD_2=32h=184.6us
PAT
Part of the POLARIS™ TOTAL RADIO™ Solution
t=-15usec
PA Ramp
RF6001 PA Ramp
BURST STARTS
Time
completed
GPO3
GPO2
GPO1
t=0usec
RF6001
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