FeaTures
n
n
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 50kΩ
•
, N
DIV
= 1,4,16 …16384
N
DIV
R
SET
n
n
n
n
n
n
n
n
n
n
n
Pulse Width Modulation (PWM) Controlled by
Simple 0V to 1V Analog Input
Four Available Options Define Duty Cycle Limits
–
Minimum Duty Cycle at 0% or 5%
–
Maximum Duty Cycle at 95% or 100%
Frequency Range: 3.81Hz to 1MHz
Configured with 1 to 3 Resistors
<1.7% Maximum Frequency Error
PWM Duty Cycle Error < 3.7% Maximum
Frequency Modulation (VCO) Capability
2.25V to 5.5V Single Supply Operation
115μA Supply Current at 100kHz
500μs Start-Up Time
CMOS Output Driver Sources/Sinks 20mA
–55°C to 125°C Operating Temperature Range
Available in Low Profile (1mm) SOT-23 (ThinSOT™)
and 2mm
×
3mm DFN
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%
applicaTions
n
n
n
n
n
PWM Servo Loops
Heater Control
LED Dimming Control
High Vibration, High Acceleration Environments
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.
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
3.3V
V
+
C1
0.1µF
SET
R
SET
50k
DIV
6992 TA01a
LTC6992
GND
MOD
0.5V/DIV
OUT
1V/DIV
2µs/DIV
6992 TA01b
69921234fc
1
LTC6992-1/LTC6992-2/
LTC6992-3/LTC6992-4
absoluTe MaxiMuM raTings
(Note 1)
Supply Voltage (V
+
) to GND .........…………………….6V
Maximum Voltage On Any Pin
.............................(GND – 0.3V) ≤ V
PIN
≤ (V
+
+ 0.3V)
Operating Temperature Range (Note 2)
LTC6992C ............................................–40°C to 85°C
LTC6992I .............................................–40°C to 85°C
LTC6992H .......................................... –40°C to 125°C
LTC6992MP ....................................... –55°C to 125°C
Specified Temperature Range (Note 3)
LTC6992C ................................................ 0°C to 70°C
LTC6992I .............................................–40°C to 85°C
LTC6992H .......................................... –40°C to 125°C
LTC6992MP ....................................... –55°C to 125°C
Junction Temperature .......................................... 150°C
Storage Temperature Range .................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
S6 Package ....................................................... 300°C
pin conFiguraTion
TOP VIEW
TOP VIEW
V+ 1
DIV 2
SET 3
7
GND
6 OUT
5 GND
4 MOD
MOD 1
GND 2
SET 3
6 OUT
5 V
+
4 DIV
DCB PACKAGE
6-LEAD (2mm
×
3mm) PLASTIC DFN
T
JMAX
= 150°C,
θ
JA
= 64°C/W,
θ
JC
= 10.6°C/W
EXPOSED PAD (PIN 7) IS GND, PCB CONNECTION IS OPTIONAL
S6 PACKAGE
6-LEAD PLASTIC TSOT-23
T
JMAX
= 150°C,
θ
JA
= 192°C/W,
θ
JC
= 51°C/W
orDer inForMaTion
Lead Free Finish
TAPE AND REEL (MINI)
TAPE AND REEL
LTC6992CDCB-1#TRMPBF LTC6992CDCB-1#TRPBF
LTC6992IDCB-1#TRMPBF
LTC6992CS6-1#TRMPBF
LTC6992IS6-1#TRMPBF
LTC6992HS6-1#TRMPBF
LTC6992CDCB-2#TRMPBF
LTC6992IDCB-2#TRMPBF
LTC6992CS6-2#TRMPBF
LTC6992IS6-2#TRMPBF
LTC6992HS6-2#TRMPBF
LTC6992CDCB-3#TRMPBF
LTC6992IDCB-3#TRMPBF
LTC6992CS6-3#TRMPBF
LTC6992IS6-3#TRMPBF
LTC6992HS6-3#TRMPBF
LTC6992IDCB-1#TRPBF
LTC6992CS6-1#TRPBF
LTC6992IS6-1#TRPBF
LTC6992HS6-1#TRPBF
LTC6992CDCB-2#TRPBF
LTC6992IDCB-2#TRPBF
LTC6992CS6-2#TRPBF
LTC6992IS6-2#TRPBF
LTC6992HS6-2#TRPBF
LTC6992CDCB-3#TRPBF
LTC6992IDCB-3#TRPBF
LTC6992CS6-3#TRPBF
LTC6992IS6-3#TRPBF
LTC6992HS6-3#TRPBF
LTC6992HDCB-1#TRMPBF LTC6992HDCB-1#TRPBF
PART MARKING*
LDXC
LDXC
LDXC
LTDXB
LTDXB
LTDXB
LDXF
LDXF
LDXF
LTDXD
LTDXD
LTDXD
LFCP
LFCP
LFCP
LTFCQ
LTFCQ
LTFCQ
PACKAGE DESCRIPTION
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead Plastic TSOT-23
6-Lead Plastic TSOT-23
6-Lead Plastic TSOT-23
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead Plastic TSOT-23
6-Lead Plastic TSOT-23
6-Lead Plastic TSOT-23
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead Plastic TSOT-23
6-Lead Plastic TSOT-23
6-Lead Plastic TSOT-23
SPECIFIED TEMPERATURE RANGE
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
69921234fc
LTC6992HDCB-2#TRMPBF LTC6992HDCB-2#TRPBF
LTC6992HDCB-3#TRMPBF LTC6992HDCB-3#TRPBF
2
LTC6992-1/LTC6992-2/
LTC6992-3/LTC6992-4
orDer inForMaTion
Lead Free Finish
TAPE AND REEL (MINI)
TAPE AND REEL
LTC6992CDCB-4#TRMPBF LTC6992CDCB-4#TRPBF
LTC6992IDCB-4#TRMPBF
LTC6992IDCB-4#TRPBF
LTC6992HDCB-4#TRMPBF LTC6992HDCB-4#TRPBF
PART MARKING*
LFCR
LFCR
LFCR
PACKAGE DESCRIPTION
6-Lead (2mm
×
3mm) Plastic DFN
6-Lead (2mm
×
3mm) Plastic DFN
SPECIFIED TEMPERATURE RANGE
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
–55°C to 125°C
–55°C to 125°C
–55°C to 125°C
–55°C to 125°C
6-Lead (2mm
×
3mm) Plastic DFN
LTC6992CS6-4#TRMPBF LTC6992CS6-4#TRPBF
LTFCS
6-Lead Plastic TSOT-23
LTC6992IS6-4#TRMPBF
LTC6992IS6-4#TRPBF
LTFCS
6-Lead Plastic TSOT-23
LTC6992HS6-4#TRMPBF LTC6992HS6-4#TRPBF
LTFCS
6-Lead Plastic TSOT-23
LTC6992MPS6-1#TRMPBF LTC6992MPS6-1#TRPBF
LTDXB
6-Lead Plastic TSOT-23
LTC6992MPS6-2#TRMPBF LTC6992MPS6-2#TRPBF
LTDXD
6-Lead Plastic TSOT-23
LTC6992MPS6-3#TRMPBF LTC6992MPS6-3#TRPBF
LTFCQ
6-Lead Plastic TSOT-23
LTC6992MPS6-4#TRMPBF LTC6992MPS6-4#TRPBF
LTFCS
6-Lead Plastic TSOT-23
TRM = 500 pieces. *Temperature grades are identified by a label on the shipping container.
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on lead based finish parts.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. Test conditions are V
+
= 2.25V to 5.5V, V
MOD
= 0V to V
SET
,
DIVCODE = 0 to 15 (N
DIV
= 1 to 16,384), R
SET
= 50k to 800k, R
LOAD
= 5k, C
LOAD
= 5pF unless otherwise noted.
SYMBOL
f
OUT
∆f
OUT
∆f
OUT
/∆T
∆f
OUT
/∆V
+
PARAMETER
Output Frequency
Frequency Accuracy (Note 4)
Frequency Drift Over Temperature
Frequency Drift Over Supply
Long-Term Frequency Stability
Period Jitter (Note 9)
V
+
= 4.5V to 5.5V
V
+
= 2.25V to 4.5V
(Note 10)
N
DIV
= 1
N
DIV
= 4
N
DIV
= 16
Pulse Width Modulation
∆D
PWM Duty Cycle Accuracy
V
MOD
= 0.2 • V
SET
to 0.8 • V
SET
V
MOD
= 0.2 • V
SET
to 0.8 • V
SET
V
MOD
< 0.2 • V
SET
or V
MOD
> 0.8 • V
SET
±3.0
l
l
elecTrical characTerisTics
Oscillation Frequency
CONDITIONS
MIN
3.81
TYP
MAX
1000000
UNITS
Hz
%
%
%/°C
%/V
%/V
ppm/√kHr
%
P-P
%
P-P
%
RMS
%
P-P
%
RMS
3.81Hz ≤ f
OUT
≤ 1MHz
l
l
l
l
±0.8
±0.005
0.25
0.08
90
1.2
0.4
0.07
0.15
0.022
±1.7
±2.4
0.65
0.18
±3.7
±4.5
±4.9
99
0
9.5
%
%
%
%
%
%
%
µs
D
MAX
D
MIN
t
S,PWM
Maximum Duty Cycle Limit
Minimum Duty Cycle Limit
Duty Cycle Settling Time (Note 6)
LTC6992-1/LTC6992-4, POL = 0, V
MOD
= 1V
l
LTC6992-2/LTC6992-3, POL = 0, V
MOD
= 1V
l
LTC6992-1/LTC6992-3, POL = 0, V
MOD
= 0V
l
LTC6992-2/LTC6992-4, POL = 0, V
MOD
= 0V
l
t
MASTER
= t
OUT
/N
DIV
100
90.5
1
95
5
8•t
MASTER
69921234fc
3
LTC6992-1/LTC6992-2/
LTC6992-3/LTC6992-4
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. Test conditions are V
+
= 2.25V to 5.5V, V
MOD
= 0V to V
SET
,
DIVCODE = 0 to 15 (N
DIV
= 1 to 16,384), R
SET
= 50k to 800k, R
LOAD
= 5k, C
LOAD
= 5pF unless otherwise noted.
SYMBOL
V
+
I
S
PARAMETER
Operating Supply Voltage Range
Power-On Reset Voltage
Supply Current
R
L
= ∞, R
SET
= 50k,
N
DIV
= 1
R
L
= ∞, R
SET
= 50k,
N
DIV
= 4
R
L
= ∞, R
SET
= 50k,
N
DIV
≥ 16
R
L
= ∞, R
SET
= 800k,
N
DIV
= 1 to 16,384
Analog Inputs
V
SET
∆V
SET
/∆T
R
SET
Voltage at SET Pin
V
SET
Drift Over Temperature
Frequency-Setting Resistor
MOD Pin Input Capacitance
MOD Pin Input Current
V
MOD,HI
V
MOD,LO
V
DIV
∆V
DIV
/∆V
+
V
MOD
Voltage for Maximum
Duty Cycle
V
MOD
Voltage for Minimum
Duty Cycle
DIV Pin Voltage
DIV Pin Valid Code Range (Note 5)
DIV Pin Input Current
Digital Output
I
OUT(MAX)
V
OH
Output Current
High Level Output Voltage (Note 7)
V
+
= 2.7V to 5.5V
V
+
= 5.5V
V
+
= 3.3V
V
+
= 2.25V
V
OL
Low Level Output Voltage (Note 7)
V
+
= 5.5V
V
+
= 3.3V
V
+
= 2.25V
t
r
t
f
Output Rise Time (Note 8)
I
OUT
= –1mA
I
OUT
= –16mA
I
OUT
= –1mA
I
OUT
= –10mA
I
OUT
= –1mA
I
OUT
= -8mA
I
OUT
= 1mA
I
OUT
= 16mA
I
OUT
= 1mA
I
OUT
= 10mA
I
OUT
= 1mA
I
OUT
= 8mA
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
elecTrical characTerisTics
CONDITIONS
l
l
MIN
2.25
TYP
MAX
5.5
1.95
UNITS
V
V
µA
µA
µA
µA
µA
µA
µA
µA
V
µV/°C
kΩ
pF
nA
V
V
V
V
Power Supply
V
+
= 5.5V
V
+
= 2.25V
V
+
= 5.5V
V
+
= 2.25V
V
+
= 5.5V
V
+
= 2.25V
V
+
= 5.5V
V
+
= 2.25V
l
l
l
l
l
l
l
l
365
225
350
225
325
215
120
105
0.97
50
2.5
1.00
±75
450
285
420
280
390
265
170
150
1.03
800
±10
LTC6992-1/LTC6992-4, POL = 0, D = 100%
LTC6992-2/LTC6992-3, POL = 0, D = 95%
LTC6992-1/LTC6992-3, POL = 0, D = 0%
LTC6992-2/LTC6992-4, POL = 0, D = 5%
Deviation from Ideal
V
DIV
/V
+
= (DIVCODE + 0.5)/16
l
l
0.064 • V
SET
l
l
l
0.90 • V
SET
0.86 • V
SET
0.10 • V
SET
0.14 • V
SET
0.936•V
SET
0
V
+
±1.5
±10nA
±20
V
%
mA
V
V
V
V
V
V
0.04
0.54
0.05
0.46
0.07
0.54
V
V
V
V
V
V
ns
ns
ns
ns
ns
ns
69921234fc
5.45
4.84
3.24
2.75
2.17
1.58
5.48
5.15
3.27
2.99
2.21
1.88
0.02
0.26
0.03
0.22
0.03
0.26
1.1
1.7
2.7
1.0
1.6
2.4
V
+
= 5.5V, R
LOAD
= ∞
V
+
= 3.3V, R
LOAD
= ∞
V
+
= 2.25V, R
LOAD
= ∞
V
+
= 5.5V, R
LOAD
= ∞
V
+
= 3.3V, R
LOAD
= ∞
V
+
= 2.25V, R
LOAD
= ∞
Output Fall Time (Note 8)
4
LTC6992-1/LTC6992-2/
LTC6992-3/LTC6992-4
elecTrical characTerisTics
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
The LTC6992C is guaranteed functional over the operating
temperature range of –40°C to 85°C.
Note 3:
The LTC6992C is guaranteed to meet specified performance from
0°C to 70°C. The LTC6992C is designed, characterized and expected to
meet specified performance from –40°C to 85°C but it is not tested or
QA sampled at these temperatures. The LTC6992I is guaranteed to meet
specified performance from –40°C to 85°C. The LTC6992H is guaranteed
to meet specified performance from –40°C to 125°C. The LTC6992MP is
guaranteed to meet specified performance from –55°C to 125°C.
Note 4:
Frequency accuracy is defined as the deviation from the f
OUT
equation, assuming R
SET
is used to program the frequency.
Note 5:
See Operation section, Table 1 and Figure 2 for a full explanation
of how the DIV pin voltage selects the value of DIVCODE.
Note 6:
Duty cycle settling time is the amount of time required for the
output to settle within ±1% of the final duty cycle after a ±10% change in
the setting (±80mV step in V
MOD
).
Note 7:
To conform to the Logic IC Standard, current out of a pin is
arbitrarily given a negative value.
Note 8:
Output rise and fall times are measured between the 10% and the
90% power supply levels with 5pF output load. These specifications are
based on characterization.
Note 9:
Jitter is the ratio of the peak-to-peak deviation of the period to the
mean of the period. This specification is based on characterization and is
not 100% tested.
Note 10:
Long-term drift of silicon oscillators is primarily due to the
movement of ions and impurities within the silicon and is tested at 30°C
under otherwise nominal operating conditions. Long-term drift is specified
as ppm/√kHr due to the typically nonlinear nature of the drift. To calculate
drift for a set time period, translate that time into thousands of hours, take
the square root and multiply by the typical drift number. For instance, a
year is 8.77kHr and would yield a drift of 266ppm at 90ppm/√kHr. Drift
without power applied to the device may be approximated as 1/10th of the
drift with power, or 9ppm/√kHr for a 90ppm/√kHr device.
Typical perForMance characTerisTics
otherwise noted.
Frequency Error vs Temperature
3
2
1
ERROR (%)
ERROR (%)
0
–1
–2
–3
–50
GUARANTEED MIN OVER TEMPERATURE
–25
75
0
25
50
TEMPERATURE (°C)
100
125
GUARANTEED MAX OVER TEMPERATURE
R
SET
= 50k
3 PARTS
3
2
1
0
–1
–2
–3
–50
V
+
= 3.3V, R
SET
= 200k, and T
A
= 25°C, unless
Frequency Error vs Temperature
GUARANTEED MAX OVER TEMPERATURE
R
SET
= 200k
3 PARTS
ERROR (%)
3
2
1
0
–1
–2
GUARANTEED MIN OVER TEMPERATURE
–25
75
0
25
50
TEMPERATURE (°C)
100
125
Frequency Error vs Temperature
GUARANTEED MAX OVER TEMPERATURE
R
SET
= 800k
3 PARTS
–3
–50
GUARANTEED MIN OVER TEMPERATURE
–25
75
0
25
50
TEMPERATURE (°C)
100
125
6992 G01
6992 G02
6992 G03
69921234fc
5