Data Sheet
26185.1
14B
Package LW
18-pin Wide Body SOIC
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
The merging of low-power CMOS logic and bipolar output power
drivers permit the A6841 integrated circuits to be used in a wide variety
of peripheral power driver applications. Each device has an eight-bit
CMOS shift register and CMOS control circuitry, eight CMOS data
latches, and eight bipolar current-sinking Darlington output drivers. The
500 mA NPN Darlington outputs, with integral transient-suppression
diodes, are suitable for use with relays, solenoids, and other inductive
loads.
All package variations of the A6841 offer premium performance with
a minimum output-breakdown voltage rating of 50 V (35 V sustaining).
All drivers can be operated with a split supply where the negative sup-
ply is up to 20 V.
The CMOS inputs are compatible with standard CMOS logic levels.
TTL circuits may require the use of appropriate pull-up resistors. By
using the serial data output, drivers can be cascaded for interface appli-
cations requiring additional drive lines.
The A6841SA devices are furnished in a standard 18-pin plastic DIP. The
A6841SLW device is available in an 18-lead SOIC package. A 20-pin
SOIC version, A6841SLW-20 has improved thermal characteristics. The
SOIC drivers are also available for operation to a temperature of 40C
(part number suffi x ELW). These devices are lead (Pb) free, with 100%
matte tin plated leadframes.
3.3 V to 5 V logic supply range
Power on reset (POR)
To 10 MHz data input rate
CMOS, TTL compatible inputs
40C operation available
Low-power CMOS logic and latches
Use the following complete part numbers when ordering:
AB SO LUTE MAX I MUM RAT INGS
Part Number
Package
Ambient
A6841SA-T
18-pin DIP
20C to +85C
A6841SLW-T
18-pin wide body SOIC
20C to +85C
A6841SLW-20-T
20-pin wide body SOIC
(enhanced thermals)
20C to +85C
A6841ELW-T
18-pin wide body SOIC
40C to +85C
A6841ELW-20-T
20-pin wide body SOIC
(enhanced thermals)
40C to +85C
Output Voltage
V
CE
..............................................................50 V
V
CE(SUS)
(for inductiove load applications) .......35 V
Logic Supply Voltage, V
DD
...................................7 V
Emitter Supply Voltage, V
EE
.............................20 V
Input Voltage Range, V
IN
..............0.3 V to V
DD
+0.3 V
Continuous Output Current (each output), I
OUT
... 500 mA
Package Power Dissipation, P
D
, see chart, page 6
Operating Temperature Range
Ambient Temperature, T
A
............20C to +85C
Storage Temperature, T
S
..........55C to +150C
Caution: CMOS devices have input-static protection,
but are susceptible to damage when exposed to
extremely high static-electrical charges.
FEATURES
Relays
Solenoids
Inductive loads
APPLICATIONS
Package A
18-pin DIP
Schmitt trigger inputs for
improved noise immunity
High-voltage current-sink outputs
Internal pull-up/pull down resistors
Output transient-protection diodes
Single or split supply operation
Package LW-20
20-pin Wide Body SOIC
2
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
Data Sheet
26185.1
14B
Functional Block Diagram
MOS
B IP OLAR
LOG IC
G R OUND
S T R OB E
OUT P UT E NAB LE
(AC T IV E LOW)
S E R IAL
DAT A OUT
C LOC K
S E R IAL
DAT A IN
S E R IAL-P AR ALLE L S HIF T R E G IS T E R
LAT C HE S
V
DD
LOG IC
S UP P LY
OUT
1
OUT
2
OUT
3
OUT
6
OUT
7
OUT
8
OUT
4
OUT
5
VE E or P OWE R G R OUND
VE E or P OWE R G R OUND
S UB
K
Typical Input Circuits
Typical Output Driver
CLOCK
SERIAL
DATA IN
V
DD
STROBE
OUTPUT
ENABLE
V
DD
OUT
SUB
K
V
EE
3
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
Data Sheet
26185.1
14B
ELECTRICAL CHARACTERISTICS
1
Unless otherwise noted: T
A
= 25C, V
ee
= 0 V, logic supply operating
voltage V
dd
= 3.0 V to 5.5 V
Characteristic
Symbol
Test Conditions
V
dd
= 3.3 V
V
dd
= 5 V
Units
Min.
Typ. Max. Min.
Typ.
Max.
Output Leakage Current
I
CEX
V
OUT
= 50 V
10
10
A
Output Sustaining Voltage
V
CE(SUS)
I
OUT
= 350 mA, L = 3 mH
35
35
V
CollectorEmitter Saturation
Voltage
V
CE(SAT)
I
OUT
= 100 mA
1.1
1.1
V
I
OUT
= 200 mA
1.3
1.3
V
I
OUT
= 350 mA
1.6
1.6
V
Input Voltage
V
IN(1)
2.2
3.3
V
V
IN(0)
1.1
1.7
V
Input Resistance
R
IN
50
50
k
Serial Data Output Voltage
V
OUT(1)
I
OUT
= 200 A
2.8
3.05
4.5
4.75
V
V
OUT(0)
I
OUT
= 200 A
0.15
0.3
0.15
0.3
V
Maximum Clock Frequency
2
f
c
10
10
MHz
Logic Supply Current
I
DD(1)
One output on, OE = L, ST = H
2.0
2.0
mA
I
DD(0)
All outputs off, OE = H, ST = H,
P1 through P8 = L
100
100
A
Clamp Diode Leakage Current
I
r
V
r
= 50 V
50
50
A
Clamp Diode Forward Voltage
V
f
I
f
= 350 mA
2
2
V
Output Enable-to-Output Delay
t
dis(BQ)
V
CC
= 50 V, R1 = 500 , C1 30 pF
1.0
1.0
s
t
en(BQ)
V
CC
= 50 V, R1 = 500 , C1 30 pF
1.0
1.0
s
Strobe-to-Output Delay
t
p(STH-QL)
V
CC
= 50 V, R1 = 500 , C1 30 pF
1.0
1.0
s
t
p(STH-QH)
V
CC
= 50 V, R1 = 500 , C1 30 pF
1.0
1.0
s
Output Fall Time
t
f
V
CC
= 50 V, R1 = 500 , C1 30 pF
1.0
1.0
s
Output Rise Time
t
r
V
CC
= 50 V, R1 = 500 , C1 30 pF
1.0
1.0
s
Clock-to-Serial Data Out Delay
t
p(CH-SQX)
I
OUT
= 200 A
50
50
ns
1
Positive (negative) current is defi ned as conventional current going into (coming out of) the specifi ed device pin.
2
Operation at a clock frequency greater than the specifi ed minimum value is possible but not warran
teed.
Serial
Shift Register Contents Serial
Latch Contents
Output
Output Contents
Data Clock
Data
Strobe
Enable
Input
Input
I
1
I
2
I
3
... I
8
Output
Input
I
1
I
2
I
3
... I
8
Input
I
1
I
2
I
3
... I
8
R
7
R
7
R
1
R
2
R
3
... R
8
R
8
X
X
X
... X
X
X
L
R
1
R
2
... R
7
L
L
R
1
R
2
R
3
... R
8
P
1
P
2
P
3
... P
8
P
8
P
1
P
2
P
3
... P
8
1
P
2
P
3
... P
8
X
X
X
... X
L
P
H
H
H
H
H
R
1
R
2
... R
7
H
H
H
...
Truth Table
L = Low Logic Level
H = High Logic Level
X = Irrelevant
P = Present State
R = Previous State
OE = Output Enable
ST = Strobe
4
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
Data Sheet
26185.1
14B
Timing Requirements and Specifi cations
(Logic Levels are V
DD
and Ground)
CLOCK
SERIAL
DATA IN
STROBE
OUTPUT ENABLE
OUT
N
50%
SERIAL
DATA OUT
DATA
DATA
10%
90%
50%
50%
50%
C
A
B
D
E
LOW = ALL OUTP UTS E NABLE D
p(STH-QL)
t
p(CH-SQX)
t
DATA
p(STH-QH)
t
OUTPUT ENABLE
OUT
N
DATA
10%
50%
dis(BQ)
t
en(BQ)
t
HIGH = ALL OUTP UTS BLANKE D (DIS ABLE D)
r
t
f
t
50%
90%
NOTE: Timing is representative of a 10 MHz clock. Higher speeds may be
attainable; operation at high temperatures will reduce the specifi ed maxi-
mum clock frequency.
Powering-on with the inputs in the low state ensures that the registers and
latches power-on in the low state (POR).
S
erial Data present at the input is transferred to the shift register on the logical
0 to logical 1 transition of the CLOCK input pulse. On succeeding CLOCK
pulses, the registers shift data information towards the SERIAL DATA OUT-
PUT. The SERIAL DATA must appear at the input prior to the rising edge of the
CLOCK input waveform.
Information present at any register is transferred to the respective latch
when the STROBE is high (serial-to-parallel conversion). The latches will
continue to accept new data as long as the STROBE is held high. Applica-
tions where the latches are bypassed (STROBE tied high) will require that
the OUTPUT ENABLE input be high during serial data entry.
When the OUTPUT ENABLE input is high, all of the output buffers are
disabled (OFF). The information stored in the latches or shift register is not
affected by the OUTPUT ENABLE input. With the OUTPUT ENABLE
input low, the outputs are controlled by the state of their respective latches.
Key
Description
Symbol
Time (ns)
A
Data Active Time Before Clock Pulse (Data Set-Up Time)
t
su(D)
25
B
Data Active Time After Clock Pulse (Data Hold Time)
t
h(D)
25
C
Clock Pulse Width
t
w(CH)
50
D
Time Between Clock Activation and Strobe
t
su(C)
100
E
Strobe Pulse Width
t
w(STH)
50
5
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
Data Sheet
26185.1
14B
Terminal List Table
Name
Description
Pin
18-pin
20-pin
VEE
Power Ground to substrate
1, 9
1, 9
CLK
Clock
2
2
DATA IN
Serial Data In
3
3
GND
Logic Ground
4
4
V
DD
Logic Supply
5
5
DATA OUT
Serial Data Out, for cascading devices
6
6
ST
Strobe
7
7
OE
Output Enable (active low)
8
8
K
Common to +V
L
, for inductive loads
10
12
NC
Not connected
10, 11
OUT
8
Sink Output 8
11
13
OUT
7
Sink Output 7
12
14
OUT
6
Sink Output 6
13
15
OUT
5
Sink Output 5
14
16
OUT
4
Sink Output 4
15
17
OUT
3
Sink Output 3
16
18
OUT
2
Sink Output 2
17
19
OUT
1
Sink Output 1
18
20
Allowable Package Power Dissipation, P
D
50
75
100
125
150
2.5
0.5
0
PO
W
E
R
D
I
S
S
I
PA
T
I
O
N
(
W
)
A MB IE NT T E MP E R A T UR E ( C )
2.0
1.5
1.0
25
18-LE AD S OIC , R
JA
= 80
C /W
20-LE AD S OIC , R
JA
= 70
C /W
18-P IN DIP , R
JA
= 60
C /W
6
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
Data Sheet
26185.1
14B
SUB
V
EE
2
3
4
5
6
7
8
SERIAL
DATA OUT
SERIAL
DATA IN
OUTPUT
ENABLE
LOGIC
SUPPLY
STROBE
LOGIC
GROUND
CLOCK
CLK
V
DD
ST
OE
1
SHIFT REGISTER
LATCHES
12
13
14
15
16
17
18
OUT
1
OUT
2
OUT
3
OUT
8
OUT
7
OUT
6
OUT
5
OUT
4
9
SUB
10
11
K
V
EE
Package LW[TBD]
(
20-pin Wide Body SOIC)
Package LW
(18-pin Wide Body SOIC)
DAT A OUT
VE E
DAT A IN
OUT P UT
E NAB LE
OUT
1
OUT
2
OUT
3
NO
C ONNE C T .
NO
C ONNE C T .
NC
NC
LOG IC S UP P LY
S T R OB E
G ND
C LOC K
OUT
6
OUT
7
OUT
8
OUT
5
OUT
4
13
14
15
16
17
19
12
18
20
11
1
2
3
8
9
4
5
6
7
10
S UB
C LK
S UB
V
DD
S T
OE
K
LA
T
C
H
E
S
SH
I
F
T
R
EG
I
S
T
E
R
VE E
18
1
Package A
(18-pin DIP)
Note the 18-pin DIP package and the SOIC
packages are electrically identical and share
common terminal number assignments.
S UB
2
3
4
5
6
7
8
S E R IAL
DAT A OUT
S E R IAL
DAT A IN
OUT P UT
E NAB LE
S T R OB E
C LOC K
+5 V 15 V
+30 V
C LK
V
DD
S T
OE
1
SH
I
F
T
R
EG
I
S
T
E
R
LA
T
C
H
E
S
12
13
14
15
16
17
18
9
S UB
10
11
Typical Application
Relay/solenoid driver using split supply
7
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
Data Sheet
26185.1
14B
Package A
18-pin DIP
0.355
0.204
7.62
BSC
Dwg. MA-001-18A mm
10.92
MAX
18
1
9
7.11
6.10
5.33
MAX
1.77
1.15
0.39
MIN
0.558
0.356
2.54
BSC
0.13
MIN
3.81
2.93
10
23.37
22.35
Dimensions in Inches
(controlling dimensions)
Dimensions in Millimeters
(for reference only)
NOTES: 1. Exact body and lead configuration at vendor's option within limits shown.
2. Lead spacing tolerance is non-cumulative.
3. Lead thickness is measured at seating plane or below.
0.014
0.008
0.300
BSC
Dwg. MA-001-18A in
0.430
MAX
18
1
9
0.280
0.240
0.210
MAX
0.070
0.045
0.015
MIN
0.022
0.014
0.100
BSC
0.005
MIN
0.150
0.115
10
0.920
0.880
8
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
Data Sheet
26185.1
14B
Package LW
18-pin Wide Body SOIC
Dimensions in Inches
(for reference only)
Dimensions in Millimeters
(controlling dimensions)
NOTES: 1. Exact body and lead configuration at vendor's option within limits shown.
2. Lead spacing tolerance is non-cumulative.
0
TO
8
1
2
3
0.020
0.013
0.0040
MIN.
0.0125
0.0091
0.050
0.016
Dwg. MA-008-18A in
0.050
BSC
18
10
0.419
0.394
0.2992
0.2914
0.4625
0.4469
0.0926
0.1043
0
TO
8
1
18
2
3
0.51
0.33
0.10
MIN.
0.32
0.23
1.27
0.40
Dwg. MA-008-18A mm
1.27
BSC
10
7.60
7.40
10.65
10.00
11.75
11.35
2.65
2.35
9
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
Data Sheet
26185.1
14B
Package LW-20
20-pin Wide Body SOIC
0
TO
8
1
2
3
0.020
0.013
0.0040
MIN.
0.0125
0.0091
0.050
0.016
Dwg. MA-008-20 in
0.050
BSC
20
11
0.2992
0.2914
0.419
0.394
0.5118
0.4961
0.0926
0.1043
0
TO
8
1
20
2
3
0.51
0.33
0.10
MIN.
Dwg. MA-008-20 mm
1.27
BSC
11
0.32
0.23
1.27
0.40
7.60
7.40
10.65
10.00
13.00
12.60
2.65
2.35
Dimensions in Inches
(for reference only)
Dimensions in Millimeters
(controlling dimensions)
NOTES: 1. Exact body and lead configuration at vendor's option within limits shown.
2. Lead spacing tolerance is non-cumulative.
10
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
A6841
DABiC-5 8-Bit Serial Input Latched Sink Drivers
Data Sheet
26185.1
14B
The products described here are manufactured under one or
more U.S. patents or U.S. patents pending.
Allegro MicroSystems, Inc. reserves the right to make, from time
to time, such de par tures from the detail spec i fi ca tions as may be
required to permit improvements in the per for mance, reliability,
or manufacturability of its products. Before placing an order, the
user is cautioned to verify that the information being relied upon is
current.
Allegro products are not authorized for use as critical compo-
nents in life-support devices or sys tems without express written
approval.
The in for ma tion in clud ed herein is believed to be ac cu rate and
reliable. How ev er, Allegro MicroSystems, Inc. assumes no re spon -
si bil i ty for its use; nor for any in fringe ment of patents or other
rights of third parties which may result from its use.
Copyright2004, 2005 AllegroMicrosystems, Inc.
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