mc13176d ETC-unknow, mc13176d Datasheet - Page 3

• Manufacturer Part Number: mc13176d
• Description: Fm/am Transmitter
• Manufacturer: ETC-unknow

MOTOROLA RF/IF DEVICE DATA
1 & 4
Pin
5
6
7
Symbol
Osc 1,
PD out
Osc 4
I Cont
V EE
1
0sc 1
10k
V EE
4.0k
I Cont
Internal Equivalent
6
V EE
V CC
5
Circuit
V CC
V CC
4.0k
V EE
PIN FUNCTION DESCRIPTIONS
Reg
Subcon
MC13175 MC13176
10k
PD out
Osc 4
7
4
CCO Inputs
The oscillator is a current controlled type. An external oscillator
coil is connected to Pins 1 and 4 which forms a parallel
resonance LC tank circuit with the internal capacitance of the
IC and with parasitic capacitance of the PC board. Three
base–emitter capacitances in series configuration form the
capacitance for the parallel tank. These are the base–emitters
at Pins 1 and 4 and the base–emitter of the differential amplifier.
The equivalent series capacitance in the differential amplifier is
varied by the modulating current from the frequency control
circuit (see Pin 6, internal circuit). A more thorough discussion
is found in the Applications Information section.
Supply Ground (V EE )
In the PCB layout, the ground pins (also applies to Pins 10 and
15) should be connected directly to chassis ground. Decoupling
capacitors to V CC should be placed directly at
Frequency Control
For V CC = 3.0 Vdc, the voltage at Pin 6 is approximately 1.55
Figure 5 shows the f osc versus I Cont at – 40 C, + 25 C and
+ 85 C for 320 MHz. The CCO may be FM modulated as shown
in Figures 18 and 19, MC13176 320 MHz FM Transmitter. A
detailed discussion is found in the Applications Information
section.
Phase Detector Output
The phase detector provides
the desired carrier frequency. The output impedance of the
phase detector is approximately 53 k . Under closed loop
conditions there is a DC voltage which is dependent upon the
free running oscillator and the reference oscillator frequencies.
The circuitry between Pins 7 and 6 should be selected for
adequate loop filtering necessary to stabilize and filter the loop
response. Low pass filtering between Pin 7 and 6 is needed so
that the corner frequency is well below the sum of the divider
and the reference oscillator frequencies, but high enough to
allow for fast response to keep the loop locked. Refer to the
Applications Information section regarding loop filtering and FM
modulation.
the ground returns.
Vdc. The oscillator is current controlled by the error current from
the phase detector. This current is amplified to drive the current
source in the oscillator section which controls the frequency of
the oscillator. Figures 9 and 10 show the f osc versus I Cont ,
Circuit Requirements
Description/External
30 A to keep the CCO locked at
3