74HC9323A Datasheet, PDF (2/6 Pages) NXP Semiconductors – Programmable ripple counter with oscillator 3-State

Philips Semiconductors
Programmable ripple counter with oscillator
(3-State)
Objective specification
74HC/HCT9323A
FEATURES
• 8-pin space saving package
• Programmable 3-stage ripple counter
• Suitable for over-tone crystal application up to 85MHz
(V_CC = 5V"10%)
• 3-State output buffer
• Two internal capacitors
• Recommended operating range for use with third overtone
crystals 3V to 6V
• Oscillator stop function (MR)
• Output capability:
bus driver ³ (15 LSTTL)
• I_CC category: MSI
APPLICATIONS
• Control counters
• Timers
• Frequency dividers
• Time-delay circuits
• CIO (Compact Integrated Oscillator)
• Third-overtone crystal operation
DESCRIPTION
The 74HC/HCT9323A are high-speed Si-gate CMOS devices. They
are specified in compliance with JEDEC standard no. 7A.
The HC/HCT 9323A are oscillators designed for quartz crystal
combined with a programmable 3-State counter, a 3-State output
buffer and an overriding asynchronous master reset (MR). With the
two select inputs S1 and S2 the counter can be switched in the
divide-1, 2, 4 or 8 mode. If left floating the clock is divided by 8. The
oscillator is designed to operate either in the fundamental or third
overtone mode depending on the crystal and external components
applied. On-chip capacitors minimize external component count for
third overtone crystal applications.
The oscillator may be replaced by an external clock signal at input
X1. In this event the other oscillator pin (X2) must be floating. The
counter advances on the negative-going transition of X1. A LOW
level on MR resets the counter, stops the oscillator and sets the
output buffer in the 3-State condition. MR can be left floating since
an internal pull-up resistor will make the MR inactive. In the HCT
version, the MR input and the two mode select pins S1 and S2 are
TTL compatible, but the X1 input has CMOS input switching levels
and may be driven by a TTL output using a pull-up resistor
connected to V_CC.
QUICK REFERENCE DATA
GND = 0V; T_amb = 25°C, t_r = t_f = 6ns
SYMBOL
PARAMETER
CONDITIONS
T_amb = 25°C; GND = 0V
t_PLH
Propagation delay
t_PHL
X1 to OUT (S1 = S2 = LOW)
C_L = 50pF; V_CC = 5V
f_max
Maximum clock frequency
C_I
Input capacitance except X1 and X2
C_PD
Power dissipation
capacitance per package
NOTES:
C_PD is used to determine the dynamic power dissipation (P_D in µW):
P_D = (C_PD V_CC2 f_I) + (C_L + V_CC2 f_O) + (I_pull-up V_CC)
where:
f_I = inputfrequency in MHz..
f_O = output frequency in MHz.
V_CC = Supply voltage in V.
C_L = Output load capacitance in pF.
I_pull-up = Pull-up currents in µA.
For HC and HCT an external clock is applied to X1 with:
t_r = t_f v 6ns, V_I is GND to V_CC, MR = HIGH.
I_pull-up is the summation of –I_I (µA) of S1 and S2 inputs at the LOW state.
TYPICAL
HC
HCT
8
8
150
150
3.5
3.5
UNIT
ns
MHz
pF
pF
ORDERING INFORMATION
PACKAGES
8-Pin Plastic SO
TEMPERATURE RANGE
0°C to +70°C
ORDER NUMBER
74HC/HCT9323A D
DWG NUMBER
SOT96-1
1995 Oct 27
2