LTC1682 - Doubler Charge Pumps with Low Noise Linear Regulator
Datasheet 
DocumentationDatasheet
Design Note
Reliability Data
LT Journal
cad_symbol
Features
- Low Output Noise: 60µVRMS (100kHz BW)
- Adjustable or Fixed Boosted Output
- Adjustable Output Voltage Range: 2.5V to 5.5V
- Fixed Output Voltages: 3.3V, 5V
- Wide Input Voltage Range: 1.8V to 4.4V
- Uses Small Ceramic Capacitors
- No Inductors Required
- Output Current up to 50mA
- 550kHz Switching Frequency
- Low Operating Current: 150µA
- Low Shutdown Current: 1µA
- Internal Thermal Shutdown and Current Limiting
- Available in 8-Pin MSOP and SO Packages
Typical Application
Description
The LTC1682/LTC1682-3.3/LTC1682-5 are doubler charge pumps with an internal low noise, low dropout (LDO) linear regulator. These parts are designed to provide a low noise boosted supply voltage for powering noise sensitive devices such as high frequency VCOs in wireless applications.An internal doubler charge pump converts a 1.8V to 4.4V input to a boosted output, while the internal LDO regulator converts the boosted voltage to a low noise regulated output. The adjustable version allows the user to set Vout via external resistors connected to FB. The regulator is capable of supplying up to 50mA of output current. Shutdown reduces the supply current to <5µA, removes the load from VIN by disabling the regulator and discharges Vout to ground through a 100Ohms switch.The LTC1682 LDO regulator is stable with only 2µF on the output. Small ceramic capacitors can be used, reducing PC board area.The LTC1682/LTC1682-3.3/LTC1682-5 are short-circuit and over temperature protected. The parts are available in 8-pin MSOP and SO packages.MS-8,SO-8
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) |
Price (1k)* |
|---|---|---|---|---|---|
| LTC1682CMS8#PBF | MSOP | 8 | C | $2.30 | $1.90 |
| LTC1682CMS8#TRPBF | MSOP | 8 | C | $1.96 | |
| LTC1682CMS8-3.3#PBF | MSOP | 8 | C | $2.30 | $1.90 |
| LTC1682CMS8-3.3#TRPBF | MSOP | 8 | C | $1.96 | |
| LTC1682CMS8-5#PBF | MSOP | 8 | C | $2.30 | $1.90 |
| LTC1682CMS8-5#TRPBF | MSOP | 8 | C | $1.96 | |
| LTC1682CS8#PBF | SO | 8 | C | $2.00 | $1.70 |
| LTC1682CS8#TRPBF | SO | 8 | C | $1.76 | |
| LTC1682CS8-3.3#PBF | SO | 8 | C | $2.00 | $1.70 |
| LTC1682CS8-3.3#TRPBF | SO | 8 | C | $1.76 | |
| LTC1682CS8-5#PBF | SO | 8 | C | $2.00 | $1.70 |
| LTC1682CS8-5#TRPBF | SO | 8 | C | $1.76 | |
| LTC1682IMS8#PBF | MSOP | 8 | I | $2.65 | $2.25 |
| LTC1682IMS8#TRPBF | MSOP | 8 | I | $2.31 | |
| LTC1682IMS8-3.3#PBF | MSOP | 8 | I | $2.65 | $2.25 |
| LTC1682IMS8-3.3#TRPBF | MSOP | 8 | I | $2.31 | |
| LTC1682IMS8-5#PBF | MSOP | 8 | I | $2.65 | $2.25 |
| LTC1682IMS8-5#TRPBF | MSOP | 8 | I | $2.31 | |
| LTC1682IS8#PBF | SO | 8 | I | $2.35 | $2.00 |
| LTC1682IS8#TRPBF | SO | 8 | I | $2.06 | |
| LTC1682IS8-3.3#PBF | SO | 8 | I | $2.35 | $2.00 |
| LTC1682IS8-3.3#TRPBF | SO | 8 | I | $2.06 | |
| LTC1682IS8-5#PBF | SO | 8 | I | $2.35 | $2.00 |
| LTC1682IS8-5#TRPBF | SO | 8 | I | $2.06 | |
| LTC1682CMS8 | MSOP | 8 | C | $4.60 | $3.80 |
| LTC1682CMS8#TR | MSOP | 8 | C | $3.92 | |
| LTC1682CMS8-3.3 | MSOP | 8 | C | $4.60 | $3.80 |
| LTC1682CMS8-3.3#TR | MSOP | 8 | C | $3.92 | |
| LTC1682CMS8-5 | MSOP | 8 | C | $4.60 | $3.80 |
| LTC1682CMS8-5#TR | MSOP | 8 | C | $3.92 | |
| LTC1682CS8 | SO | 8 | C | $4.00 | $3.40 |
| LTC1682CS8#TR | SO | 8 | C | $3.52 | |
| LTC1682CS8-3.3 | SO | 8 | C | $4.00 | $3.40 |
| LTC1682CS8-3.3#TR | SO | 8 | C | $3.52 | |
| LTC1682CS8-5 | SO | 8 | C | $4.00 | $3.40 |
| LTC1682CS8-5#TR | SO | 8 | C | $3.52 | |
| LTC1682IMS8 | MSOP | 8 | I | $5.30 | $4.50 |
| LTC1682IMS8#TR | MSOP | 8 | I | $4.62 | |
| LTC1682IMS8-3.3 | MSOP | 8 | I | $5.30 | $4.50 |
| LTC1682IMS8-3.3#TR | MSOP | 8 | I | $4.62 | |
| LTC1682IMS8-5 | MSOP | 8 | I | $5.30 | $4.50 |
| LTC1682IMS8-5#TR | MSOP | 8 | I | $4.62 | |
| LTC1682IS8 | SO | 8 | I | $4.70 | $4.00 |
| LTC1682IS8#TR | SO | 8 | I | $4.12 | |
| LTC1682IS8-3.3 | SO | 8 | I | $4.70 | $4.00 |
| LTC1682IS8-3.3#TR | SO | 8 | I | $4.12 | |
| LTC1682IS8-5 | SO | 8 | I | $4.70 | $4.00 |
| LTC1682IS8-5#TR | SO | 8 | I | $4.12 |
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 |
|---|---|---|---|
| DC249A-A | LTC1682CMS8 | Doubler Charge Pump with Linear Regulator, Adjustable, 1.8 to 4.4Vin, 2.5 to 5.5Vout @ 50mA | Contact Factory | |
| DC249A-B | LTC1682CMS8-5 | Doubler Charge Pump with Linear Regulator, Fixed, 2.7 to 4.4Vin, 5.0Vout @ 50mA | Contact Factory | |
| DC249A-C | LTC1682CMS8-3.3 | Doubler Charge Pump with Linear Regulator, Fixed, 2.0 to 4.4Vin, 3.3Vout @ 50mA | Contact Factory | |
| DC332A | LTC1682CMS8 | White LED Driver, 3.0V to 4.2V Input, 75mA Output (5 White LEDs) | Contact Factory |