Datasheet LT6660 (Analog Devices) - 8
| Manufacturer | Analog Devices |
| Description | Tiny Micropower Precision Series References in 2mm × 2mm DFN |
| Pages / Page | 12 / 8 — APPLICATIO S I FOR ATIO. Longer Battery Life. Figure 2. CL = 0µF. … |
| File Format / Size | PDF / 415 Kb |
| Document Language | English |
APPLICATIO S I FOR ATIO. Longer Battery Life. Figure 2. CL = 0µF. Capacitive Loads. Figure 3. CL = 0.1µF. Figure 4. IOUT = 1mA
Model Line for this Datasheet
- LT6660HCDC-10#PBF LT6660HCDC-10#TRMPBF LT6660HCDC-10#TRPBF LT6660HCDC-2.5#PBF LT6660HCDC-2.5#TRMPBF LT6660HCDC-2.5#TRPBF LT6660HCDC-3#PBF LT6660HCDC-3#TRMPBF LT6660HCDC-3#TRPBF LT6660HCDC-3.3#PBF LT6660HCDC-3.3#TRMPBF LT6660HCDC-3.3#TRPBF LT6660HCDC-5#PBF LT6660HCDC-5#TRMPBF LT6660HCDC-5#TRPBF LT6660JCDC-10#PBF LT6660JCDC-10#TRMPBF LT6660JCDC-10#TRPBF LT6660JCDC-2.5#PBF LT6660JCDC-2.5#TRMPBF LT6660JCDC-2.5#TRPBF LT6660JCDC-3#PBF LT6660JCDC-3#TRMPBF LT6660JCDC-3#TRPBF LT6660JCDC-3.3#PBF LT6660JCDC-3.3#TRMPBF LT6660JCDC-3.3#TRPBF LT6660JCDC-5#PBF LT6660JCDC-5#TRMPBF LT6660JCDC-5#TRPBF LT6660KCDC-10#PBF LT6660KCDC-10#TRMPBF LT6660KCDC-10#TRPBF LT6660KCDC-2.5#PBF LT6660KCDC-2.5#TRMPBF LT6660KCDC-2.5#TRPBF LT6660KCDC-3#PBF LT6660KCDC-3#TRMPBF LT6660KCDC-3#TRPBF LT6660KCDC-3.3#PBF LT6660KCDC-3.3#TRMPBF LT6660KCDC-3.3#TRPBF LT6660KCDC-5#PBF LT6660KCDC-5#TRMPBF LT6660KCDC-5#TRPBF
Text Version of Document
LT6660
U U W U APPLICATIO S I FOR ATIO Longer Battery Life
Series references have a large advantage over older shunt VGEN 2.5V style references. Shunt references require a resistor 1.5V from the power supply to operate. This resistor must be chosen to supply the maximum current that can ever be VOUT 1mA demanded by the circuit being regulated. When the circuit being controlled is not operating at this maximum current, VOUT 10mA the shunt reference must always sink this current, resulting in high dissipation and short battery life. 1µs/DIV 6660 F02 The LT6660 series references do not require a current setting resistor and can operate with any supply voltage
Figure 2. CL = 0µF
from VOUT + 0.9V to 20V. When the circuitry being regu- lated does not demand current, the LT6660s reduce their dissipation and battery life is extended. If the references are not delivering load current, they dissipate only several VGEN 2.5V mW, yet the same connection can deliver 20mA of load 1.5V current when demanded. VOUT 1mA
Capacitive Loads
V 10mA The LT6660 family of references are designed to be stable OUT with a large range of capacitive loads. With no capacitive load, these references are ideal for fast settling or applica- 100µs/DIV 6660 F03 tions where PC board space is a premium. The test circuit shown in Figure 1 is used to measure the response time
Figure 3. CL = 0.1µF
and stability of various load currents and load capacitors. This circuit is set for the 2.5V option. For other voltage options, the input voltage must be scaled up and the output voltage generator offset voltage must be adjusted. VGEN 2.5V The 1V step from 2.5V to 1.5V produces a current step of 1.5V 10mA or 1mA for RL = 100Ω or RL = 1k. Figure 2 shows the response of the reference to these 1mA and 10mA VOUT 1µF load steps with no load capacitance, and Figure 3 shows a 1mA and 10mA load step with a 0.1µF output capaci- VOUT 4.7µF tor. Figure 4 shows the response to a 1mA load step with CL = 1µF and 4.7µF. 100µs/DIV 6660 F04
Figure 4. IOUT = 1mA
R V L OUT VIN = 2.5V LT6660-2.5 VGEN C 2.5V IN 0.1µF CL 1.5V 6660 F01
Figure 1. Response Time Test Circuit
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U U W U APPLICATIO S I FOR ATIO Longer Battery Life
Series references have a large advantage over older shunt VGEN 2.5V style references. Shunt references require a resistor 1.5V from the power supply to operate. This resistor must be chosen to supply the maximum current that can ever be VOUT 1mA demanded by the circuit being regulated. When the circuit being controlled is not operating at this maximum current, VOUT 10mA the shunt reference must always sink this current, resulting in high dissipation and short battery life. 1µs/DIV 6660 F02 The LT6660 series references do not require a current setting resistor and can operate with any supply voltage
Figure 2. CL = 0µF
from VOUT + 0.9V to 20V. When the circuitry being regu- lated does not demand current, the LT6660s reduce their dissipation and battery life is extended. If the references are not delivering load current, they dissipate only several VGEN 2.5V mW, yet the same connection can deliver 20mA of load 1.5V current when demanded. VOUT 1mA
Capacitive Loads
V 10mA The LT6660 family of references are designed to be stable OUT with a large range of capacitive loads. With no capacitive load, these references are ideal for fast settling or applica- 100µs/DIV 6660 F03 tions where PC board space is a premium. The test circuit shown in Figure 1 is used to measure the response time
Figure 3. CL = 0.1µF
and stability of various load currents and load capacitors. This circuit is set for the 2.5V option. For other voltage options, the input voltage must be scaled up and the output voltage generator offset voltage must be adjusted. VGEN 2.5V The 1V step from 2.5V to 1.5V produces a current step of 1.5V 10mA or 1mA for RL = 100Ω or RL = 1k. Figure 2 shows the response of the reference to these 1mA and 10mA VOUT 1µF load steps with no load capacitance, and Figure 3 shows a 1mA and 10mA load step with a 0.1µF output capaci- VOUT 4.7µF tor. Figure 4 shows the response to a 1mA load step with CL = 1µF and 4.7µF. 100µs/DIV 6660 F04
Figure 4. IOUT = 1mA
R V L OUT VIN = 2.5V LT6660-2.5 VGEN C 2.5V IN 0.1µF CL 1.5V 6660 F01
Figure 1. Response Time Test Circuit
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