LTC6992-3_15 Datasheet, PDF (1/34 Pages) Linear Technology – Voltage-Controlled Pulse Width Modulator

Features
n _{Pulse Width Modulation (PWM) Controlled by}
Simple 0V to 1V Analog Input
n _{Four Available Options Define Duty Cycle Limits}
– Minimum Duty Cycle at 0% or 5%
– Maximum Duty Cycle at 95% or 100%
n _{Frequency Range: 3.81Hz to 1MHz}
n _{Configured with 1 to 3 Resistors}
n _{<1.7% Maximum Frequency Error}
n _{PWM Duty Cycle Error < 3.7% Maximum}
n _{Frequency Modulation (VCO) Capability}
n _{2.25V to 5.5V Single Supply Operation}
n _{115μA Supply Current at 100kHz}
n _{500μs Start-Up Time}
n _{CMOS Output Driver Sources/Sinks 20mA}
n _{–55°C to 125°C Operating Temperature Range}
n _{Available in Low Profile (1mm) SOT-23 (ThinSOT™)}
and 2mm × 3mm DFN
Applications
n _{PWM Servo Loops}
n _{Heater Control}
n _{LED Dimming Control}
n _{High Vibration, High Acceleration Environments}
n _{Portable and Battery-Powered Equipment}
L, LT, LTC and LTM, Linear Technology, TimerBlox and the Linear logo are registered
trademarks and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
LTC6992-1/LTC6992-2/
LTC6992-3/LTC6992-4
TimerBlox:
Voltage-Controlled Pulse
Width Modulator (PWM)
Description
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.
A single resistor, R_SET, programs the LTC6992’s inter-
nal master oscillator frequency. The output frequency
is determined by this master oscillator and an internal
frequency divider, N_DIV, programmable to eight settings
from 1 to 16384.
f_OUT
=
1MHz
N_DIV
•
50kΩ
R_SET
,
N_DIV
=
1,4,16
…16384
Applying a voltage between 0V and 1V on the MOD pin
sets the duty cycle.
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.
DEVICE NAME
LTC6992-1
LTC6992-2
LTC6992-3
LTC6992-4
PWM DUTY CYCLE RANGE
0% to 100%
5% to 95%
0% to 95%
5% to 100%
For easy configuration of the LTC6992, download the
TimerBlox Designer tool at www.linear.com/timerblox.
Typical Application
1MHz Pulse Width Modulator
ANALOG PWM
DUTY CYCLE
CONTROL
(0V TO 1V)
MOD OUT
LTC6992
GND
V⁺
SET
R_SET
50k
DIV
6992 TA01a
3.3V
C1
0.1µF
MOD
0.5V/DIV
OUT
1V/DIV
2µs/DIV
6992 TA01b
69921234fc
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