Datasheet LTC7803 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 40V Low IQ, 3MHz Synchronous Step-Down Controller with Spread Spectrum |
| Pages / Page | 36 / 1 — FEATURES. DESCRIPTION. Low Operating IQ: 12µA (14V VIN to 3.3V VOUT). … |
| File Format / Size | PDF / 1.6 Mb |
| Document Language | English |
FEATURES. DESCRIPTION. Low Operating IQ: 12µA (14V VIN to 3.3V VOUT). Wide Input Voltage Range: 4.5V to 40V
Model Line for this Datasheet
- LTC7803EMSE#PBF LTC7803EMSE#TRPBF LTC7803EMSE#WPBF LTC7803EMSE#WTRPBF LTC7803EUD#PBF LTC7803EUD#TRPBF LTC7803EUD#WPBF LTC7803EUD#WTRPBF LTC7803HMSE#PBF LTC7803HMSE#TRPBF LTC7803HMSE#WPBF LTC7803HMSE#WTRPBF LTC7803HUD#PBF LTC7803HUD#TRPBF LTC7803HUD#WPBF LTC7803HUD#WTRPBF LTC7803IMSE#PBF LTC7803IMSE#TRPBF LTC7803IMSE#WPBF LTC7803IMSE#WTRPBF LTC7803IUD#PBF LTC7803IUD#TRPBF LTC7803IUD#WPBF LTC7803IUD#WTRPBF LTC7803JMSE#PBF LTC7803JMSE#TRPBF LTC7803JMSE#WPBF LTC7803JMSE#WTRPBF LTC7803JUD#PBF LTC7803JUD#TRPBF LTC7803JUD#WPBF LTC7803JUD#WTRPBF
Text Version of Document
LTC7803 40V Low IQ, 3MHz Synchronous Step-Down Controller with Spread Spectrum
FEATURES DESCRIPTION
n
Low Operating IQ: 12µA (14V VIN to 3.3V VOUT)
The LTC®7803 is a high performance, 100% Duty Cycle n
Wide Input Voltage Range: 4.5V to 40V
Capable, synchronous step-down DC/DC switching n
Output Voltage Up to 40V
regulator controller that drives an all N-channel power n
Spread Spectrum Operation
MOSFET stage. Synchronous rectification increases effi- n
RSENSE or DCR Current Sensing
ciency, reduces power losses and eases thermal require- n
PassThru™/100% Duty Cycle Capable
ments. A constant frequency current mode architecture n Programmable Fixed Frequency (100kHz to 3MHz) allows a phase-lockable switching frequency of up to n Phase-Lockable Frequency (100kHz to 3MHz) 3MHz. The LTC7803 operates from a wide 4.5V to 40V n Selectable Continuous, Pulse-Skipping, or Low input supply range. Ripple Burst Mode® Operation at Light Loads The very low no-load quiescent current extends operating n Low Shutdown IQ: 1.2μA runtime in battery powered systems. OPTI-LOOP com- n Thermally Enhanced 16-Pin 3mm × 3mm QFN and pensation allows the transient response to be optimized MSOP Packages over a wide range of output capacitance and ESR values. n AEC-Q100 Qualification in Progress The MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous inductor current
APPLICATIONS
mode at light loads. n The LTC7803 additionally features spread spectrum oper- Automotive and Transportation n ation which significantly reduces the peak radiated and Industrial n conducted noise on both the input and output supplies, Military/Avionics n making it easier to comply with electromagnetic interfer- Telecommunications ence (EMI) standards. All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620, 6144194, 6177787, 6580258.
TYPICAL APPLICATION High Efficiency Wide Input Range 375kHz 3.3V/20A Step-Down Regulator Efficiency vs Output Current Efficiency vs Output Current
RUN V 100 10k IN VIN + V 5V TO 38V OUT = 3.3V 10µF 56µF TRACK//SS TG ×2 ×4 ×2 90 1k ITH BOOST 0.68µH VOUT 0.1µF 0.1µF 1mΩ LTC7803 80 6.19k 39pF SW 3.3V + 20A BG ×2 470µF 70 100 4.7nF INTVCC 100µF 60 10 ×4 4.7µF EFFICIENCY (%) VIN = 12V 50 VIN = 24V PLLIN/SPREAD SENSE+ VIN = 36V 1 40 MODE BURST MODE OPERATION SENSE– FIGURE 11 CIRCUIT FREQ EXTV 215k 30 0.1 CC 0.0001 0.001 0.01 0.1 1 10 GND VFB OUTPUT CURRENT (A) 7803 TA01b 68.1k 7803 TA01a Rev 0 Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Package Description Typical Application Related Parts
FEATURES DESCRIPTION
n
Low Operating IQ: 12µA (14V VIN to 3.3V VOUT)
The LTC®7803 is a high performance, 100% Duty Cycle n
Wide Input Voltage Range: 4.5V to 40V
Capable, synchronous step-down DC/DC switching n
Output Voltage Up to 40V
regulator controller that drives an all N-channel power n
Spread Spectrum Operation
MOSFET stage. Synchronous rectification increases effi- n
RSENSE or DCR Current Sensing
ciency, reduces power losses and eases thermal require- n
PassThru™/100% Duty Cycle Capable
ments. A constant frequency current mode architecture n Programmable Fixed Frequency (100kHz to 3MHz) allows a phase-lockable switching frequency of up to n Phase-Lockable Frequency (100kHz to 3MHz) 3MHz. The LTC7803 operates from a wide 4.5V to 40V n Selectable Continuous, Pulse-Skipping, or Low input supply range. Ripple Burst Mode® Operation at Light Loads The very low no-load quiescent current extends operating n Low Shutdown IQ: 1.2μA runtime in battery powered systems. OPTI-LOOP com- n Thermally Enhanced 16-Pin 3mm × 3mm QFN and pensation allows the transient response to be optimized MSOP Packages over a wide range of output capacitance and ESR values. n AEC-Q100 Qualification in Progress The MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous inductor current
APPLICATIONS
mode at light loads. n The LTC7803 additionally features spread spectrum oper- Automotive and Transportation n ation which significantly reduces the peak radiated and Industrial n conducted noise on both the input and output supplies, Military/Avionics n making it easier to comply with electromagnetic interfer- Telecommunications ence (EMI) standards. All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620, 6144194, 6177787, 6580258.
TYPICAL APPLICATION High Efficiency Wide Input Range 375kHz 3.3V/20A Step-Down Regulator Efficiency vs Output Current Efficiency vs Output Current
RUN V 100 10k IN VIN + V 5V TO 38V OUT = 3.3V 10µF 56µF TRACK//SS TG ×2 ×4 ×2 90 1k ITH BOOST 0.68µH VOUT 0.1µF 0.1µF 1mΩ LTC7803 80 6.19k 39pF SW 3.3V + 20A BG ×2 470µF 70 100 4.7nF INTVCC 100µF 60 10 ×4 4.7µF EFFICIENCY (%) VIN = 12V 50 VIN = 24V PLLIN/SPREAD SENSE+ VIN = 36V 1 40 MODE BURST MODE OPERATION SENSE– FIGURE 11 CIRCUIT FREQ EXTV 215k 30 0.1 CC 0.0001 0.001 0.01 0.1 1 10 GND VFB OUTPUT CURRENT (A) 7803 TA01b 68.1k 7803 TA01a Rev 0 Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Package Description Typical Application Related Parts
