AD6634BBC Analog Devices Inc, AD6634BBC Datasheet - Page 42

• Manufacturer Part Number: AD6634BBC
• Description: IC,RF/Baseband Circuit,CMOS,BGA,196PIN,PLASTIC
• Manufacturer: Analog Devices Inc
• Series: AD6634r

Specifications of AD6634BBC

• Rohs Status: RoHS non-compliant
• Rf Type: Cellular, CDMA2000, EDGE, GPRS, GSM
• Number Of Mixers: 1
• Voltage - Supply: 3 V ~ 3.6 V
• Package / Case: 196-CSPBGA
• Current - Supply: -
• Frequency: -
• Gain: -
• Noise Figure: -
• Secondary Attributes: -

AD6634
be dual-channel and determined by the state of the IENA pin. If the
IENA pin is low, the input detection is directed to LIA-A. If the
IENA pin is high, the input is directed to LIA-B. In either case,
Bit 4 determines the actual polarity of these signals.
Bits 2–0 determine the internal latency of the gain detect function.
When the LIA-A,B pins are made active, they are typically used
to change an attenuator or gain stage. Since this is prior to the
ADC, there is a latency associated with the ADC and with the
settling of the gain change. This register allows the internal delay
of the LIA-A,B signal to be programmed.
0x04 Lower Threshold B
This word is 10 bits wide and maps to the 10 most significant
bits of the mantissa. If the upper 10 bits of input port B are less
than or equal to this value, the lower threshold has been met. In
normal chip operation, this starts the dwell time counter. If the
input signal increases above this value, the counter is reloaded
and awaits the input to drop back to this level.
0x05 Upper Threshold B
This word is 10 bits wide and maps to the 10 most significant
bits of the mantissa. If the upper 10 bits of input port B are greater
than or equal to this value, the upper threshold has been met.
In normal chip operation, this will cause the appropriate LI pin
(LIB-A or LIB-B) to become active.
0x06 Dwell Time B
This sets the time that the input signal must be at or below the
lower threshold before the LI pin is deactivated. For the input
level detector to work, the dwell time must be set to at least 1.
If set to 0, the LI functions are disabled.
–42–
This is a 20-bit register. When the lower threshold is met following
an excursion into the upper threshold, the dwell time counter is
loaded and begins to count high speed clock cycles as long as the
input is at or below the lower threshold. If the signal increases above
the lower threshold, the counter is reloaded and waits for the signal
to fall below the lower threshold again.
0x07 Gain Range B Control Register
Bit 4 determines the polarity of LIB-A and LIB-B. If this bit is
clear then the LI signal is high when the upper threshold has
been exceeded. However, if this bit is set, the LI pin is low when
active. This allows maximum flexibility when using this function.
Bit 3 determines if the input consists of a single channel or TDM
channels such as when using the AD6600. If this bit is cleared,
a single ADC is assumed. In this mode, LIB-A functions as the
active output indicator. LIB-B provides the complement of LIB-A.
However if this bit is set, the input is determined to be dual
channel and determined by the state of the IENB pin. If the
IENB pin is low, the input detection is directed to LIB-A. If the
IENB pin is high, the input is directed to LIB-B. In either case,
Bit 4 determines the actual polarity of these signals.
Bits 2–0 determine the internal latency of the gain detect function.
When the LIB-A,B pins are made active, they are typically used
to change an attenuator or gain stage. Since this is prior to the
ADC, there is a latency associated with the ADC and with the
settling of the gain change. This register allows the internal delay
of the LIB-A,B signal to be programmed.
REV. 0