sm5128a1s Nippon Precision Circuits Inc, (NPC), sm5128a1s Datasheet - Page 7

• Manufacturer Part Number: sm5128a1s
• Description: Cb Transceiver System Lsi
• Manufacturer: Nippon Precision Circuits Inc, (NPC)

Chattering Elimination Circuit
A high-speed chattering elimination circuit is incor-
porated in pins UP and DN. The chattering elimina-
tion circuit recognizes the input state only after the
Note that the input is recognized during the LOW-
level pulse interval, t
clock.
CE
CE is the chip enable pin. Normal operation is
selected when CE is HIGH, and standby mode is
selected when CE is LOW. CE incorporates a pull-
down resistor.
In standby mode, the following states occur.
PA
PA is the PA display mode select pin. PA mode is
selected when pin PA is HIGH. When PA is open,
PLL operation is restored. PA incorporates a pull-
down resistor.
In PA display mode, PLL operation is stopped and
the following states occur.
All pins except CE are ignored.
Crystal oscillator is stopped. XIN is HIGH, and
XOUT is LOW.
PLL operation is stopped. DO and LD are high
impedance, AI and FIN are HIGH, and AO and
CHO are LOW.
Display segments are all OFF. COMA, COMB,
COMC, and S1 to S6 are LOW.
Current channel selection is stored.
FIN and AI are HIGH.
CHO is LOW.
DO and LD are high impedance.
Current channel selection is stored.
“HIGH POWER” and “LOW POWER” display
indicators are OFF.
SAMPLING CLOCK
(Internal)
Chatering circuits
OUTPUT
INPUT
S
(32 ms), of the sampling
DISCONTINUED
PRODUCT
3.2 to 9.6ms
SM5128A1
input has been continuously LOW or HIGH for a
period of 3.2 to 6.4 ms. The output does not change
if the input state lasts less than 3.2 ms.
TR
TR is the transmit/receive select pin. Transmit is
selected when TR is HIGH, and receive is selected
when TR is LOW or open. When transmit mode is
selected, the channel up/down control is disabled,
and the state of pin EMG is accepted. TR incorpo-
rates a pull-down resistor.
3.2 to 9.6ms
NIPPON PRECISION CIRCUITS—7
3.2ms(ts)
6.4ms