Datasheet LT1767, LT1767-1.8, LT1767-2.5, LT1767-3.3, LT1767-5 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Monolithic 1.5A, 1.25MHz Step-Down Switching Regulators |
| Pages / Page | 20 / 1 — FeaTures. DescripTion. 1.5A Switch in a Small MSOP Package. Constant … |
| File Format / Size | PDF / 441 Kb |
| Document Language | English |
FeaTures. DescripTion. 1.5A Switch in a Small MSOP Package. Constant 1.25MHz Switching Frequency
Model Line for this Datasheet
- LT1767EMS8#PBF LT1767EMS8#TRPBF LT1767EMS8-1.8#PBF LT1767EMS8-1.8#TRPBF LT1767EMS8-2.5#PBF LT1767EMS8-2.5#TRPBF LT1767EMS8-3.3#PBF LT1767EMS8-3.3#TRPBF LT1767EMS8-5#PBF LT1767EMS8-5#TRPBF LT1767EMS8E#PBF LT1767EMS8E#TRPBF LT1767EMS8E-1.8#PBF LT1767EMS8E-1.8#TRPBF LT1767EMS8E-2.5#PBF LT1767EMS8E-2.5#TRPBF LT1767EMS8E-3.3#PBF LT1767EMS8E-3.3#TRPBF LT1767EMS8E-5#PBF LT1767EMS8E-5#TRPBF
Text Version of Document
LT1767/LT1767-1.8/ LT1767-2.5/LT1767-3.3/LT1767-5 Monolithic 1.5A, 1.25MHz Step-Down Switching Regulators
FeaTures DescripTion
n
1.5A Switch in a Small MSOP Package
The LT®1767 is a 1.25MHz monolithic buck switching n
Constant 1.25MHz Switching Frequency
regulator. A high efficiency 1.5A, 0.22Ω switch is included n
High Power Exposed Pad (MS8E) Package
on the die together with all the control circuitry required n
Wide Operating Voltage Range: 3V to 25V
to complete a high frequency, current mode switching n
High Efficiency 0.22Ω Switch
regulator. Current mode control provides fast transient n
1.2V Feedback Reference Voltage
response and excellent loop stability. n
Fixed Output Voltages of 1.8V, 2.5V, 3.3V, 5V
New design techniques achieve high efficiency at high n
2% Overall Output Tolerance
switching frequencies over a wide operating range. A n Uses Low Profile Surface Mount Components low dropout internal regulator maintains consistent per- n Low Shutdown Current: 6µA formance over a wide range of inputs from 24V systems n Synchronizable to 2MHz to Li-Ion batteries. An operating supply current of 1mA n Current Mode Loop Control improves efficiency, especially at lower output currents. n Constant Maximum Switch Current Rating at All Duty Shutdown reduces quiescent current to 6µA. Maximum Cycles* switch current remains constant at all duty cycles. Syn- chronization allows an external logic level signal to increase
applicaTions
the internal oscillator from 1.5MHz to 2MHz. n DSL Modems The LT1767 is available in an 8-pin MSOP fused lead-frame n Portable Computers package and a low thermal resistance exposed pad package. n Wall Adapters Full cycle-by-cycle current limit and thermal shutdown are n Battery-Powered Systems provided. High frequency operation allows the reduction n Distributed Power of input and output filtering components and permits the use of chip inductors. L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 6611131, 6498466.
Typical applicaTion Efficiency vs Load Current 12V to 3.3V Step-Down Converter
95 D2 CMDSH-3 VIN = 10V 90 VOUT = 5V C2 0.1µF L1 85 BOOST 5µH OUTPUT VIN VIN V 3.3V 12V SW C3 OPEN LT1767-3.3 1.2A* 80 2.2µF EFFICIENCY (%) CERAMIC OR SHDN FB HIGH = ON SYNC GND VC C1 75 CC D1 10µF 1.5nF UPS120 CERAMIC RC 70 4.7k 0 0.2 0.4 0.6 0.8 1 1.2 1.4 LOAD CURRENT (A) *MAXIMUM OUTPUT CURRENT IS SUBJECT TO THERMAL DERATING. 1767 TA01 1767 TA01a 1767fb For more information www.linear.com/LT1767 1 Document Outline Description Typical Application Absolute Maximum Ratings Electrical Characteristics Typical Application
FeaTures DescripTion
n
1.5A Switch in a Small MSOP Package
The LT®1767 is a 1.25MHz monolithic buck switching n
Constant 1.25MHz Switching Frequency
regulator. A high efficiency 1.5A, 0.22Ω switch is included n
High Power Exposed Pad (MS8E) Package
on the die together with all the control circuitry required n
Wide Operating Voltage Range: 3V to 25V
to complete a high frequency, current mode switching n
High Efficiency 0.22Ω Switch
regulator. Current mode control provides fast transient n
1.2V Feedback Reference Voltage
response and excellent loop stability. n
Fixed Output Voltages of 1.8V, 2.5V, 3.3V, 5V
New design techniques achieve high efficiency at high n
2% Overall Output Tolerance
switching frequencies over a wide operating range. A n Uses Low Profile Surface Mount Components low dropout internal regulator maintains consistent per- n Low Shutdown Current: 6µA formance over a wide range of inputs from 24V systems n Synchronizable to 2MHz to Li-Ion batteries. An operating supply current of 1mA n Current Mode Loop Control improves efficiency, especially at lower output currents. n Constant Maximum Switch Current Rating at All Duty Shutdown reduces quiescent current to 6µA. Maximum Cycles* switch current remains constant at all duty cycles. Syn- chronization allows an external logic level signal to increase
applicaTions
the internal oscillator from 1.5MHz to 2MHz. n DSL Modems The LT1767 is available in an 8-pin MSOP fused lead-frame n Portable Computers package and a low thermal resistance exposed pad package. n Wall Adapters Full cycle-by-cycle current limit and thermal shutdown are n Battery-Powered Systems provided. High frequency operation allows the reduction n Distributed Power of input and output filtering components and permits the use of chip inductors. L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 6611131, 6498466.
Typical applicaTion Efficiency vs Load Current 12V to 3.3V Step-Down Converter
95 D2 CMDSH-3 VIN = 10V 90 VOUT = 5V C2 0.1µF L1 85 BOOST 5µH OUTPUT VIN VIN V 3.3V 12V SW C3 OPEN LT1767-3.3 1.2A* 80 2.2µF EFFICIENCY (%) CERAMIC OR SHDN FB HIGH = ON SYNC GND VC C1 75 CC D1 10µF 1.5nF UPS120 CERAMIC RC 70 4.7k 0 0.2 0.4 0.6 0.8 1 1.2 1.4 LOAD CURRENT (A) *MAXIMUM OUTPUT CURRENT IS SUBJECT TO THERMAL DERATING. 1767 TA01 1767 TA01a 1767fb For more information www.linear.com/LT1767 1 Document Outline Description Typical Application Absolute Maximum Ratings Electrical Characteristics Typical Application
