Philips Semiconductors
Product specification
SA612A
Double-balanced mixer and oscillator
1997 Nov 07
3
ABSOLUTE MAXIMUM RATINGS
SYMBOL
PARAMETER
RATING
UNIT
VCC
Maximum operating voltage
9
V
TSTG
Storage temperature
-65 to +150
°C
TA
Operating ambient temperature range SA612A
-40 to +85
°C
AC/DC ELECTRICAL CHARACTERISTICS
TA=25°C, VCC = 6V, Figure 3
SYMBOL
PARAMETER
TEST CONDITION
LIMITS
UNIT
SYMBOL
PARAMETER
TEST CONDITION
Min
Typ
Max
UNIT
VCC
Power supply voltage range
4.5
8.0
V
DC current drain
2.4
3.0
mA
fIN
Input signal frequency
500
MHz
fOSC
Oscillator frequency
200
MHz
Noise figured at 45MHz
5.0
dB
Third-order intercept point at 45MHz
RFIN=-45dBm
-13
dBm
Conversion gain at 45MHz
14
17
dB
RIN
RF input resistance
1.5
k
CIN
RF input capacitance
3
pF
Mixer output resistance
(Pin 4 or 5)
1.5
k
DESCRIPTION OF OPERATION
The SA612A is a Gilbert cell, an oscillator/buffer, and a temperature
compensated bias network as shown in the equivalent circuit. The
Gilbert cell is a differential amplifier (Pins 1 and 2) which drives a
balanced switching cell. The differential input stage provides gain
and determines the noise figure and signal handling performance of
the system.
The SA612A is designed for optimum low power performance.
When used with the SA614A as a 45MHz cordless phone/cellular
radio 2nd IF and demodulator, the SA612A is capable of receiving
-119dBm signals with a 12dB S/N ratio. Third-order intercept is
typically -15dBm (that’s approximately +5dBm output intercept
because of the RF gain). The system designer must be cognizant of
this large signal limitation. When designing LANs or other closed
systems where transmission levels are high, and small-signal or
signal-to-noise issues not critical, the input to the SA612A should be
appropriately scaled.