DocumentationDatasheet
cad_symbol
Features
- No Current Sense Resistor Required
- VOUT up to 60V
- Constant Frequency 550kHz Operation
- Internal Soft-Start and Optional External Soft-Start
- Adjustable Current Limit
- Pulse Skipping at Light Load
- VIN Range: 2.75V to 9.8V
- ±1.5% Voltage Reference Accuracy
- Current Mode Operation for Excellent Line and Load Transient Response
- Low Profile (1mm) SOT-23 and 2mm × 3mm DFN Packages
Typical Application
Description
The LTC®3872-1 is a constant frequency current mode boost DC/DC controller that drives an N-channel power MOSFET and requires very few external components. The No RSENSETM architecture eliminates the need for a sense resistor, improves efficiency and saves board space.
The LTC3872-1 provides excellent AC and DC load and line regulation with ±1.5% output voltage accuracy. It incorporates an undervoltage lockout feature that shuts down the device when the input voltage falls below 2.3V.
LTC3872-1 has the same functionality as the standard LTC3872 except that it has no frequency foldback in current limit.
High switching frequency of 550kHz allows the use of a small inductor. The LTC3872-1 is available in an 8-lead low profile (1mm) ThinSOTTM package and 8-pin 2mm × 3mm DFN package.
| LTC3872 | LTC3872-1 | |
|---|---|---|
| Frequency Foldback In Current Limit | Yes | No |
3x2 DFN-8,SOT-23
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) |
Price (1k)* |
|---|---|---|---|---|---|
| LTC3872EDDB#PBF | DFN | 8 | E | $2.57 | |
| LTC3872EDDB#TRMPBF | DFN | 8 | E | $2.57 | $1.85 |
| LTC3872EDDB#TRPBF | DFN | 8 | E | $2.57 | $1.80 |
| LTC3872EDDB-1#PBF | DFN | 8 | E | $2.57 | |
| LTC3872EDDB-1#TRMPBF | DFN | 8 | E | $2.57 | $1.85 |
| LTC3872EDDB-1#TRPBF | DFN | 8 | E | $2.57 | $1.80 |
| LTC3872ETS8#PBF | SOT | 8 | E | $2.57 | |
| LTC3872ETS8#TRMPBF | SOT | 8 | E | $2.57 | $1.85 |
| LTC3872ETS8#TRPBF | SOT | 8 | E | $2.57 | $1.80 |
| LTC3872ETS8-1#PBF | SOT | 8 | E | $2.57 | |
| LTC3872ETS8-1#TRMPBF | SOT | 8 | E | $2.57 | $1.85 |
| LTC3872ETS8-1#TRPBF | SOT | 8 | E | $2.57 | $1.80 |
| LTC3872HDDB#PBF | DFN | 8 | H | $3.36 | |
| LTC3872HDDB#TRMPBF | DFN | 8 | H | $3.36 | $2.40 |
| LTC3872HDDB#TRPBF | DFN | 8 | H | $3.36 | $2.35 |
| LTC3872HDDB-1#PBF | DFN | 8 | H | $3.36 | |
| LTC3872HDDB-1#TRMPBF | DFN | 8 | H | $3.36 | $2.40 |
| LTC3872HDDB-1#TRPBF | DFN | 8 | H | $3.36 | $2.35 |
| LTC3872HTS8#PBF | SOT | 8 | H | $3.36 | |
| LTC3872HTS8#TRMPBF | SOT | 8 | H | $3.36 | $2.40 |
| LTC3872HTS8#TRPBF | SOT | 8 | H | $3.36 | $2.35 |
| LTC3872HTS8-1#PBF | SOT | 8 | H | $3.36 | |
| LTC3872HTS8-1#TRMPBF | SOT | 8 | H | $3.36 | $2.40 |
| LTC3872HTS8-1#TRPBF | SOT | 8 | H | $3.36 | $2.35 |
| LTC3872IDDB#PBF | DFN | 8 | I | $2.96 | |
| LTC3872IDDB#TRMPBF | DFN | 8 | I | $2.96 | $2.12 |
| LTC3872IDDB#TRPBF | DFN | 8 | I | $2.96 | $2.07 |
| LTC3872IDDB-1#PBF | DFN | 8 | I | $2.96 | |
| LTC3872IDDB-1#TRMPBF | DFN | 8 | I | $2.96 | $2.12 |
| LTC3872IDDB-1#TRPBF | DFN | 8 | I | $2.96 | $2.07 |
| LTC3872ITS8#PBF | SOT | 8 | I | $2.96 | |
| LTC3872ITS8#TRMPBF | SOT | 8 | I | $2.96 | $2.12 |
| LTC3872ITS8#TRPBF | SOT | 8 | I | $2.96 | $2.07 |
| LTC3872ITS8-1#PBF | SOT | 8 | I | $2.96 | |
| LTC3872ITS8-1#TRMPBF | SOT | 8 | I | $2.96 | $2.12 |
| LTC3872ITS8-1#TRPBF | SOT | 8 | I | $2.96 | $2.07 |
| LTC3872ETS8#TRM | SOT | 8 | E | $5.14 | $3.70 |
| LTC3872ETS8#TR | SOT | 8 | E | $5.14 | $3.60 |
| LTC3872ETS8 | SOT | 8 | E | $5.14 | |
| LTC3872ETS8-1 | SOT | 8 | E | $5.14 | |
| LTC3872ETS8-1#TR | SOT | 8 | E | $5.14 | $3.60 |
| LTC3872ETS8-1#TRM | SOT | 8 | E | $5.14 | $3.70 |
| LTC3872ITS8 | SOT | 8 | I | $5.92 | |
| LTC3872ITS8-1 | SOT | 8 | I | $5.92 | |
| LTC3872ITS8-1#TR | SOT | 8 | I | $5.92 | $4.14 |
| LTC3872HTS8 | SOT | 8 | H | $6.72 | |
| LTC3872HTS8-1 | SOT | 8 | H | $6.72 | |
| LTC3872HTS8-1#TR | SOT | 8 | H | $6.72 | $4.70 |
| LTC3872EDDB-1 | DFN | 8 | E | $5.14 | |
| LTC3872EDDB-1#TR | DFN | 8 | E | $5.14 | $3.60 |
| LTC3872IDDB | DFN | 8 | I | $5.92 | |
| LTC3872IDDB-1 | DFN | 8 | I | $5.92 | |
| LTC3872IDDB-1#TR | DFN | 8 | I | $5.92 | $4.14 |
| LTC3872HDDB | DFN | 8 | H | $6.72 | |
| LTC3872HDDB-1 | DFN | 8 | H | $6.72 | |
| LTC3872HDDB-1#TR | DFN | 8 | H | $6.72 | $4.70 |
| LTC3872EDDB | DFN | 8 | E | $5.14 |
Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.
| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC989B-B | LTC3872-1ETS8 Demo Board | 2.75V ≤ VIN ≤ 4.5V; VOUT: 5V @ 2A | $75.00 |