Rev 2.0 ©2010 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, CA 94089-1706 Tel: (408) 747-1155 Fax: (408) 747-1286
www.aldinc.com
ADVANCED
LINEAR
DEVICES, INC.
QUAD PRECISION HIGH SPEED MICROPOWER TIMER
ALD4501
PIN CONFIGURATION
BLOCK DIAGRAM (EACH TIMER)
V
+
OUT
1
THRES
1
OUT
2
THRES
2
OUT
3
THRES
3
OUT
4
CONT
DSC
1
TRIG
1
DSC
2
TRIG
2
DSC
3
TRIG
3
DSC
4
TRIG
4
THRES
4
V
-
RST 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
OUTPUT
DISCHARGE
RESET
R
S
R
R
R
TRIGGER
CONTROL
THRESHOLD
V
+
V
-
* Contact factory for leaded (non-RoHS) or high temperature versions.
Operating Temperature Range *
0°C to +70°C0°C to +70°C -55°C to +125°C
20-Pin Small Outline 20-Pin Plastic 20-Pin CERDIP
Package (SOIC) DIP Package Package
ALD4501SEL ALD4501PEL ALD4501DE
ORDERING INFORMATION (“L” suffix denotes lead-free (RoHS))
GENERAL DESCRIPTION
The ALD4501 timer is a high performance QUAD monolithic timing
circuit built with advanced silicon gate CMOS technology. It offers the
benefits of high input impedance, thereby allowing smaller timing
capacitors and longer timing cycle; high speed with typical cycle time of
500ns; low power dissipation for battery operated environment; and
reduced supply current spikes allowing smaller and lower cost decoupling
capacitors. Each of the four timers can be independently operated in
either the monostable, astable, or 50% duty cycle mode.
Each timer is capable of producing accurate time delays and oscillations
in both monostable and astable operation. It operates in the one-shot
(monostable) mode or 50% duty cycle free running oscillation mode with
a single resistor and one capacitor. The inputs and outputs are fully
compatible with CMOS, NMOS or TTL logic.
There are three matched internal resistors (approximately 200KΩ each)
that set the threshold and trigger levels at two-thirds and one-third
respectively of V
+
. These levels can be adjusted by using the control
terminal. When the trigger input is below the trigger level, the output is
in the high state and sourcing 2mA. When the threshold input is above
the threshold level at the same time the trigger input is above the trigger
level, the internal flip-flop is reset, the output goes to the low state and
sinks up to 10mA. The reset input overrides all other inputs and when
it is active (reset voltage less than 1V), the output is in the low state. All
four timers share the same control and reset pins so that timing functions
are synchronized.
FEATURES
• High speed operation -- 2MHz typical oscillation at 5V
• Each discharge output sinking current: 40mA at 5V
• Guaranteed low operating supply voltage of 2 to 12V
• Each timer is functionally equivalent to NE555 with greatly expanded
high and low frequency ranges
• High speed, low power, monolithic CMOS technology
• Low supply current: 150µA typical
• Extremely low trigger, threshold and reset currents: 10pA typical
• Operates in both monostable and astable modes
• Fixed 50% duty cycle or adjustable duty cycle
• CMOS, NMOS and TTL compatible input/output
• Low supply current spikes
APPLICATIONS
.
• High speed one-shot (monostable)
pulse generation
• Precision timing
• Sequential timing
• Long delay timer
• Pulse width and pulse position
modulation
• Missing pulse detector
• Frequency divider
• Synchronized timer
SEL, PEL, DE PACKAGES
