Datasheet LT8648S (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 42V, 15A Synchronous Step-Down Silent Switcher 2 |
| Pages / Page | 28 / 1 — FEATURES. DESCRIPTION. Silent Switcher. 2 Architecture. Ultralow EMI … |
| File Format / Size | PDF / 2.2 Mb |
| Document Language | English |
FEATURES. DESCRIPTION. Silent Switcher. 2 Architecture. Ultralow EMI Emissions on Any PCB. Eliminates PCB Layout Sensitivity
Model Line for this Datasheet
Text Version of Document
LT8648S 42V, 15A Synchronous Step-Down Silent Switcher 2
FEATURES DESCRIPTION
n
Silent Switcher
®
2 Architecture
The LT®8648S synchronous step-down regulator n
Ultralow EMI Emissions on Any PCB
features second generation Silent Switcher architecture n
Eliminates PCB Layout Sensitivity
designed to minimize EMI emissions while delivering high n
Internal Bypass Capacitors Reduce Radiated EMI
efficiency at high switching frequencies. This includes n
Optional Spread Spectrum Modulation
the integration of input and boost capacitors to optimize n
High Efficiency at High Frequency
all the fast current loops inside and make it easy to n achieve advertised EMI performance by reducing layout
Up to 95.5% Efficiency at 1MHz, 12VIN to 5VOUT
n sensitivity. This performance makes the LT8648S ideal for
Up to 93% Efficiency at 2MHz, 12VIN to 5VOUT
n noise sensitive applications and environments.
Wide Input Voltage Range: 3V to 42V
n
15A Output Current
The fast, clean, low overshoot switching edges enable high n Low Quiescent Current Burst Mode® Operation efficiency operation even at high switching frequencies, n 100µA IQ Regulating 12VIN to 5VOUT leading to a small overall solution size. Peak current mode n Output Ripple < 10mVP-P control with a 25ns minimum on-time allows high step n External Compensation: Fast Transient Response and down ratios even at high switching frequencies. External Current Sharing compensation via the VC pin allows for fast transient n Fast Minimum Switch On-Time: 25ns response at high switching frequencies. The VC pin n Low Dropout Under All Conditions: 35mV at 1A also enables current sharing and a CLKOUT pin enables n Forced Continuous Mode synchronizing other regulators to the LT8648S. n Adjustable and Synchronizable: 200kHz to 2.2MHz Burst Mode operation enables low standby current n Output Soft-Start and Power Good consumption, forced continuous mode can control n Safely Tolerates High Reverse Current frequency harmonics across the entire output load n Small 36-Lead 7mm × 4mm LQFN Package range, or spread spectrum operation can further reduce n AEC-Q100 Qualification in Progress EMI emissions. Soft-start and tracking functionality is accessed via the SS pin, and an accurate input voltage
APPLICATIONS
UVLO threshold can be set using the EN/UV pin. n Automotive and Industrial Supplies All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. patents, including 8823345. n General Purpose Step-Down
TYPICAL APPLICATION 12V 12V IN IN to 5V to 5V OUT OUT Efficiency Efficiency
100 8
5V 15A Step-Down Converter
95 7 V 90 IN EFFICIENCY 6 V POWER LOSS (W) 5.4V TO 42V IN 10µF 85 5 EN/UV 1µH VOUT SW 5V 80 4 15A POWER LOSS INTVCC BIAS 75 3 EFFICIENCY (%) 1µF 13.7k LT8648S V 10pF 100k 70 2 C 47µF 400kHz, L = 2.2µH RT FB x2 65 1MHz, L = 1µH 1 330pF 38.3k 13.7k 2MHz, L = 0.68µH GND 60 0 1 3 5 7 9 11 13 15 fSW = 1MHz 8648S TA01a LOAD CURRENT (A) 8648S TA01b Rev. 0 Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Applications Related Parts
FEATURES DESCRIPTION
n
Silent Switcher
®
2 Architecture
The LT®8648S synchronous step-down regulator n
Ultralow EMI Emissions on Any PCB
features second generation Silent Switcher architecture n
Eliminates PCB Layout Sensitivity
designed to minimize EMI emissions while delivering high n
Internal Bypass Capacitors Reduce Radiated EMI
efficiency at high switching frequencies. This includes n
Optional Spread Spectrum Modulation
the integration of input and boost capacitors to optimize n
High Efficiency at High Frequency
all the fast current loops inside and make it easy to n achieve advertised EMI performance by reducing layout
Up to 95.5% Efficiency at 1MHz, 12VIN to 5VOUT
n sensitivity. This performance makes the LT8648S ideal for
Up to 93% Efficiency at 2MHz, 12VIN to 5VOUT
n noise sensitive applications and environments.
Wide Input Voltage Range: 3V to 42V
n
15A Output Current
The fast, clean, low overshoot switching edges enable high n Low Quiescent Current Burst Mode® Operation efficiency operation even at high switching frequencies, n 100µA IQ Regulating 12VIN to 5VOUT leading to a small overall solution size. Peak current mode n Output Ripple < 10mVP-P control with a 25ns minimum on-time allows high step n External Compensation: Fast Transient Response and down ratios even at high switching frequencies. External Current Sharing compensation via the VC pin allows for fast transient n Fast Minimum Switch On-Time: 25ns response at high switching frequencies. The VC pin n Low Dropout Under All Conditions: 35mV at 1A also enables current sharing and a CLKOUT pin enables n Forced Continuous Mode synchronizing other regulators to the LT8648S. n Adjustable and Synchronizable: 200kHz to 2.2MHz Burst Mode operation enables low standby current n Output Soft-Start and Power Good consumption, forced continuous mode can control n Safely Tolerates High Reverse Current frequency harmonics across the entire output load n Small 36-Lead 7mm × 4mm LQFN Package range, or spread spectrum operation can further reduce n AEC-Q100 Qualification in Progress EMI emissions. Soft-start and tracking functionality is accessed via the SS pin, and an accurate input voltage
APPLICATIONS
UVLO threshold can be set using the EN/UV pin. n Automotive and Industrial Supplies All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. patents, including 8823345. n General Purpose Step-Down
TYPICAL APPLICATION 12V 12V IN IN to 5V to 5V OUT OUT Efficiency Efficiency
100 8
5V 15A Step-Down Converter
95 7 V 90 IN EFFICIENCY 6 V POWER LOSS (W) 5.4V TO 42V IN 10µF 85 5 EN/UV 1µH VOUT SW 5V 80 4 15A POWER LOSS INTVCC BIAS 75 3 EFFICIENCY (%) 1µF 13.7k LT8648S V 10pF 100k 70 2 C 47µF 400kHz, L = 2.2µH RT FB x2 65 1MHz, L = 1µH 1 330pF 38.3k 13.7k 2MHz, L = 0.68µH GND 60 0 1 3 5 7 9 11 13 15 fSW = 1MHz 8648S TA01a LOAD CURRENT (A) 8648S TA01b Rev. 0 Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Applications Related Parts
