CONTROL IC. NJM2287 Datasheet
100MHz INPUT MIXER AND 450kHz IF GAIN CONTROL IC
The NJM2287 is an IF Gain Control IC with 450kHz (standard) IF input,
which operates from 2.7V to 5.5V supply. It includes a local-buffer, mixer,
IF gain control amplifier, and RSSI circuit.
The NJM2287 is especially designed for digital transceivers with built-in
an analog gain control amplifier and a subsequent analog to digital converter
The useful functions of the NJM2287 are rail-to-rail output swing of 3Vpp
@3.3V and wide gain control of over 80dB. These features help streamline
the subsequent circuit design.
Low Operating Current
Maximum Mixer Input Frequency
Wide IF Gain Control Range
Rail - to - rail Output
Wide Range RSSI
2.7V to 5.5V
4.7mA @V+ = 3.3V, no signal
100MHz (reference value)
3Vp-p @V+ = 3.3V
over 70dB (linear area)
LO DEC LO IN
V+2 RSSI IF OUT GC IN
RF DEC RF IN
GND1 MIX OUT GND2
1 RF DEC
2 RF IN
4 MIX OUT
6 IF IN
7 IF DEC
8 GC IN
9 IF OUT
13 LO IN
14 LO DEC
FM IF Output
Representative Block Diagram
RSSI IF Signal
1u 1000p 1u 1000p
14 13 12 11 10
Simplified Application Block Diagram
Symbols related to Electrical Characteristics
G IF1 (to 4)
Current consumption 1
The current passing through pin12 (V+1) when V+1 is supplied to pin 12. No input signal.
Current consumption 2
The current passing through pin11 (V+2) when V+2 is supplied to pin 11. No input signal.
Supply current 1 at GC IN / GC IN supply current 1
The current passing through pin8 (GC IN) when the voltage at pin8 is 0V.
Supply current 2 at GC IN / GC IN supply current 2
The current passing through pin8 (GC IN) when the voltage at pin8 is 2V.
Mixer input frequency at RF IN / RF IN input frequency
The suitable frequency range of RF input signal at pin2 (RF IN). At this frequency range, the output
signal at pin4 satisfies the gain flatness of within ±3dB.
Mixer Conversion Gain
The difference between the output signal level at pin4 and the input signal level at pin2
Mixer input 1dB compression point
The RF input signal level at 1dB compression point.
Mixer 3rd order intercept point
The RF signal level at 3rd order interrupt point, where FIMIX1=45MHz, FIMIX2=FIMIX1-6.25kHz
Noise level at MIX OUT / MIX OUT noise level
The noise level at pin4 (MIX OUT) within the frequency range from 450-3.125kHz to
450+3.125kHz Note: This range means the center frequency is 450kHz and the BW is 6.25kHz.
Input level at LO IN / LO IN input level
The suitable level of local input signal at pin13 (LO IN). At this frequency range, the output signal at
pin4 (MIX OUT) satisfies the gain flatness of within ±3dB.
Input resistance at RF IN / RF IN input resistance
The resistance between pin 1 (RF DEC) and pin2 (RF IN)
Input resistance at LO IN / LO IN input resistance
The resistance between pin13 (LO IN) and pin14 (LO DEC)
Output resistance at MIX OUT / MIX output resistance
The AC resistance at pin 4(MIX OUT) within the range from 450-3.125kHz to 450+3.125kHz
Input frequency at IF IN / IF IN input frequency
The suitable frequency range of IF input signal at pin6 (IF IN). At this frequency range, the output
signal level at pin9 (IF OUT) is satisfied with the gain flatness of within ±3dB.
IF gain at each of the different GC IN voltage.
IF Input 1dB Compression point
The IF input signal level at 1dB compression point.
Noise level at IF OUT / IF OUT noise level
The noise level at pin9 (IF OUT) within the range from 450-3.125kHz to 450+3.125kHz
Maximum output voltage at IF OUT / IF OUT maximum output voltage
The maximum output level at pin9 (IF OUT) when input level at pin6 is 30dBuV.
Input resistance at IF IN / IF IN input resistance
The resistance between pin 6 (IF IN) and pin9 (IF OUT).
The RSSI output level at different IF IN input level
Gain control range
The range of IF gain change with GC IN voltage.
The ratio of IF gain change with GC IN voltage