Harman Kardon HK 3370, Service Manual

Page: 95 / 123

Pin Functions
Note: * The high and low level input voltages for the CE, CL, DI, IN0 and IN1 pins are V
IH
= 2.2 to 6.5 V and V
IL
= 0 to 0.7 V, regardless of the power
supply voltage V
DD
.
No. 4758-6/16
LC7218, 7218M, 7218JM
Pin No. Symbol I/O Type Function
1
24
19
18
21
22
6
20
23
2
4
3
5
X
IN
X
OUT
FMIN
AMIN
PD1
PD2
SYC
V
DD
V
SS
CE
CL
DI
DO
Input
Output
Input
Input
Three-state
N-channel
open drain
—
—
Input *
Input *
Input *
Output
(N-channel
open drain)
Xtal OSC
Local oscillator signal
input
Local oscillator signal
input
Charge pump outputs
Controller clock
Power supply
Ground
Chip enable
Clock
Input data
Output data
• Connections for a 7.2 MHz crystal oscillator
• FMIN is selected when DV in the serial input data is set to 1.
• Input frequency range: 10 to 130 MHz (70 mVrms minimum)
• The signal passes through an internal divide-by-two prescaler and is then supplied to
the swallow counter.
• Although the divisor setting is in the range 256 to 65,536, the actual divisor will be twice
the set value due to the presence of the internal divide-by-two prescaler.
• AMIN is selected when DV in the serial input data is set to 0.
• When SP in the serial input data is set to 1:
— Input frequency range: 2 to 40 MHz (70 mVrms minimum).
— The signal is supplied directly to the swallow counter without passing through the
internal divide-by-two prescaler.
— The divisor setting is in the range 256 to 65,536 and the actual divisor will be the
value set.
• When SP in the serial input data is set to 0:
— Input frequency range: 0.5 to 10 MHz (70 mVrms minimum).
— The signal is supplied directly to a 12-bit programmable divider.
— The divisor setting is in the range 4 to 4,096 and the actual divisor will be the
value set.
• PLL charge pump outputs. High levels are output from PD1 and PD2 when the local
oscillator frequency divided by n is higher than the reference frequency, and low levels
are output when that frequency is lower than the reference frequency.
These pins go to the floating state when the frequencies agree.
• SYC is a controller clock source. The LC7218 outputs a 400 kHz 66% duty signal
from this pin after power is applied.
• The LC7218 power supply pin. A voltage of between 4.5 and 6.5 V must be provided
when the PLL is operating. The supply voltage can be lowered to 3.5 V when only
operating the crystal oscillator circuit to acquire the controller clock and the clock time
base outputs.
• The LC7218 ground pin
• This pin must be set high when inputting serial data (via DI) or when outputting serial
data (via DO).
• The clock input used for data signal synchronization during serial data input (via DI) or
output (via DO).
• Input pin used when transferring serial data from the controller to the LC7218.
• A total of 36 bits of data must be supplied to set up the LC7218 initial state.
• Output pin used when transferring serial data to the controller from the LC7218.
• A total of 28 bits from an internal shift register can be output in synchronization with the
CL signal.
Continued on next page.
hk3370/hk3470 harman/kardon
95