Philips Semiconductors
Octal D-type flip-flop with data enable;
positive-edge trigger
Product specification
74AHC377; 74AHCT377
FEATURES
• ESD protection:
HBM EIA/JESD22-A114-A exceeds 2000 V
MM EIA/JESD22-A115-A exceeds 200 V
CDM EIA/JESD22-C101 exceeds 1000 V
• Balanced propagation delays
• All inputs have Schmitt-trigger actions
• Inputs accept voltages higher than VCC
• Ideal for addressable register applications
• Data enable for address and data synchronization
• Eight positive-edge triggered D-type flip-flops
• See “273” for master reset version
• See “373” for transparent latch version
• See “374” for 3-state version
• For AHC only: operates with CMOS input levels
• For AHCT only: operates with TTL input levels
• Specified from −40 to +85 and from −40 to +125 °C.
DESCRIPTION
The 74AHC/AHCT377 D-type flip-flops are high-speed
silicon-gate CMOS devices and are pin compatible with
low power Schottky TTL (LSTTL). They are specified in
compliance with JEDEC standard No. 7A.
The 74AHC/AHCT377 devices have eight edge-triggered,
D-type flip-flops with individual D inputs and Q outputs.
A common clock (CP) input loads all flip-flops
simultaneously when the data enable (E) is LOW. The
state of each D input, one set-up time before the
LOW-to-HIGH clock transition, is transferred to the
corresponding output (Qn) of the flip-flop.
The E input must be stable only one set-up time prior to the
LOW-to-HIGH transition for predictable operation.
QUICK REFERENCE DATA
GND = 0 V; Tamb = 25 °C; tr = tf ≤ 3.0 ns.
SYMBOL
PARAMETER
CONDITIONS
tPHL/tPLH
fmax
CI
CPD
propagation delay;
CP to Qn
maximum clock frequency
input capacitance
power dissipation
capacitance
CL = 15 pF; VCC = 5 V
CL = 15 pF; VCC = 5 V
VI = VCC or GND
CL = 50 pF; f = 1 MHz;
notes 1 and 2
Notes
1. CPD is used to determine the dynamic power dissipation (PD in µW).
PD = CPD × VCC2 × fi + ∑ (CL × VCC2 × fo) where:
fi = input frequency in MHz;
fo = output frequency in MHz;
∑ (CL × VCC2 × fo) = sum of outputs;
CL = output load capacitance in pF;
VCC = supply voltage in Volts.
2. The condition is VI = GND to VCC.
TYPICAL
AHC
3.9
AHCT
4.0
UNIT
ns
175
140 MHz
3.0
3.0
pF
20
23
pF
2000 Aug 15
2