Electrical Specifications Subject to Change
LTC6992-1/-2/-3/-4
TimerBlox
Voltage-Controlled Pulse
Width Modulator (PWM)
FEATURES
DESCRIPTION
n
Pulse Width Modulation (PWM) Controlled by
The LTC®6992 is a silicon oscillator with an easy-to-use
analog voltage-controlled pulse width modulation (PWM)
capability. The LTC6992 is part of the TimerBlox™ family
of versatile silicon timing devices.
Simple 0V to 1V Analog Input
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Four Available Options Define Duty Cycle Limits
– Minimum Duty Cycle at 0% or 5%
– Maximum Duty Cycle at 95% or 100%
A single resistor, R , programs the LTC6992’s inter-
SET
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Frequency Range: 3.81Hz to 1MHz
nal master oscillator frequency. The output frequency
is determined by this master oscillator and an internal
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Single Resistor Programs Frequency with <2.4%
Maximum Error
frequency divider, N , programmable to eight settings
DIV
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PWM Duty Cycle Error <4.5% Maximum
from 1 to 16384.
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Frequency Modulation (VCO) Capability
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1MHz 50kΩ
NDIV RSET
2.25V to 5.5V Single Supply Operation
fOUT
=
•
,NDIV = 1,4,16 …16384
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115μA Supply Current at 100kHz
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500μs Start-Up Time
Applyingavoltagebetween0Vand1VontheMODpinsets
the duty cycle, according to the following formula:
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CMOS Output Driver Sources/Sinks 20mA
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–40°C to 125°C Operating Temperature Range
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VMOD
0.8 • VSET
VMOD −100mV
1
8
Available in Low Profile (1mm) SOT-23 (ThinSOT™)
Duty Cycle =
−
≅
and 2mm × 3mm DFN
800mV
The four versions differ in their minimum/maximum duty
cycle. Note that a minimum duty cycle limit of 0% or
maximum duty cycle limit of 100% allows oscillations to
stop at the extreme duty cycle settings.
APPLICATIONS
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LED Dimming Control
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PWM Servo Loops
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High Vibration, High Acceleration Environments
OUTPUT DUTY CYCLE LIMITS
PWM DUTY
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Portable and Battery-Powered Equipment
DEVICE NAME
LTC6992-1
LTC6992-2
LTC6992-3
LTC6992-4
CYCLE RANGE
0% to 100%
5% to 95%
MIN
GND
MAX
V
+
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
TimerBlox and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
0% to 95%
GND
+
5% to 100%
V
TYPICAL APPLICATION
1MHz Pulse Width Modulator
ANALOG PWM
DUTY CYCLE
MOD
MOD
GND
SET
OUT
CONTROL
(0V TO 1V)
0.5V/DIV
LTC6992
+
V
+
V
C1
0.1ꢀF
OUT
1V/DIV
DIV
6992 TA01a
R
SET
50k
6992 TA01b
2ꢀs/DIV
69921234p
1