Philips Semiconductors
Product data
74ABT16821A
74ABTH16821A
20-bit bus-interface D-type flip-flop;
positive-edge trigger (3-State)
2
2002 Dec 13
FEATURES
20-bit positive-edge triggered register
Multiple V
CC and GND pins minimize switching noise
Live insertion/extraction permitted
Power-up reset
Power-up 3-State
74ABTH16821A incorporates bus-hold data inputs which
eliminate the need for external pull-up resistors to hold unused
inputs
Output capability: +64 mA / –32 mA
Latch-up protection exceeds 500mA per JEDEC Std 17
ESD protection exceeds 2000V per MIL STD 883 Method 3015
and 200V per Machine Model
DESCRIPTION
The 74ABT16821A high-performance BiCMOS device combines
low static and dynamic power dissipation with high speed and high
output drive.
The 74ABT16821A has two 10-bit, edge triggered registers, with
each register coupled to a 3-State output buffer. The two sections of
each register are controlled independently by the clock (nCP) and
Output Enable (nOE) control gates.
Each register is fully edge triggered. The state of each D input, one
set-up time before the LOW-to-HIGH clock transition, is transferred
to the corresponding flip-flop’s Q output.
The 3-State output buffers are designed to drive heavily loaded
3-State buses, MOS memories, or MOS microprocessors.
The active-LOW Output Enable (nOE) controls all ten 3-State
buffers independent of the register operation. When nOE is LOW,
the data in the register appears at the outputs. When nOE is HIGH,
the outputs are in high impedance “off” state, which means they will
neither drive nor load the bus.
Two options are available, 74ABT16821A which does not have the
bus-hold feature and 74ABTH16821A which incorporates the
bus-hold feature.
QUICK REFERENCE DATA
SYMBOL
PARAMETER
CONDITIONS
Tamb = 25 °C; GND = 0 V
TYPICAL
UNIT
tPLH
tPHL
Propagation delay
nCP to nQx
CL = 50 pF; VCC = 5 V
2.4
2.0
ns
CIN
Input capacitance
VI = 0 V or VCC
3
pF
COUT
Output capacitance
VO = 0 V or VCC; 3-State
7
pF
ICCZ
Quiescent supply current
Outputs disabled; VCC = 5.5 V
500
A
ICCL
Quiescent supply current
Outputs LOW; VCC = 5.5 V
10
mA
ORDERING INFORMATION
PACKAGES
TEMPERATURE RANGE
PART NUMBER
DWG NUMBER
56-Pin Plastic SSOP Type III
–40
°C to +85 °C
74ABT16821ADL
SOT371-1
56-Pin Plastic TSSOP Type II
–40
°C to +85 °C
74ABT16821ADGG
SOT364-1
56-Pin Plastic TSSOP Type II
–40
°C to +85 °C
74ABTH16821ADGG
SOT364-1
PIN DESCRIPTION
PIN NUMBER
SYMBOL
FUNCTION
55, 54, 52, 51, 49, 48, 47, 45, 44, 43,
42, 41, 40, 38, 37, 36, 34, 33, 31, 30
1D0 – 1D9
2D0 – 2D9
Data inputs
2, 3, 5, 6, 8, 9, 10, 12, 13, 14,
15, 16, 17, 19, 20, 21, 23, 24, 26, 27
1Q0 – 1Q9
2Q0 – 2Q9
Data outputs
1, 28
1OE, 2OE
Output enable inputs (active-LOW)
56, 29
1CP, 2CP
Clock pulse inputs (active rising edge)
4, 11, 18, 25, 32, 39, 46, 53
GND
Ground (0 V)
7, 22, 35, 50
VCC
Positive supply voltage