Datasheet LT8609, LT8609A, LT8609B (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 42V, 2A/3A Peak Synchronous Step-Down Regulator with 2.5µA Quiescent Current |
| Pages / Page | 26 / 1 — FEATURES. DESCRIPTION. Wide Input Voltage Range: 3.0V to 42V. Ultralow … |
| File Format / Size | PDF / 1.5 Mb |
| Document Language | English |
FEATURES. DESCRIPTION. Wide Input Voltage Range: 3.0V to 42V. Ultralow Quiescent Current Burst Mode® Operation:
Text Version of Document
LT8609/LT8609A/LT8609B 42V, 2A/3A Peak Synchronous Step-Down Regulator with 2.5µA Quiescent Current
FEATURES DESCRIPTION
n
Wide Input Voltage Range: 3.0V to 42V
The LT®8609/LT8609A/LT8609B is a compact, high ef- n
Ultralow Quiescent Current Burst Mode® Operation:
ficiency, high speed synchronous monolithic step-down n
<2.5µA IQ Regulating 12VIN to 3.3VOUT
switching regulator that consumes only 1.7µA of non- n
Output Ripple <10mVP-P
switching quiescent current. The LT8609/LT8609A/LT8609B n
High Efficiency 2MHz Synchronous Operation:
can deliver 2A of continuous current with peak loads of n
>93% Efficiency at 1A, 5VOUT from 12VIN
3A (<1sec). Burst Mode operation enables high efficiency n
2A Maximum Continuous Output, 3A Peak
down to very low output currents while keeping the output
Transient Output
ripple below 10mVP-P. A SYNC pin allows synchronization to n
Fast Minimum Switch-On Time: 45ns
an external clock, or spread spectrum modulation for low EMI n
Adjustable and Synchronizable: 200kHz to 2.2MHz
operation. Internal compensation with peak current mode n
Spread Spectrum Frequency Modulation for Low EMI
topology allows the use of small inductors and results in fast n Allows Use of Small Inductors transient response and good loop stability. The EN/UV pin n Low Dropout has an accurate 1V threshold and can be used to program n Peak Current Mode Operation VIN UVLO or to shut down the part. A capacitor on the TR/SS n Accurate 1V Enable Pin Threshold pin programs the output voltage ramp rate during start-up n Internal Compensation while the PG flag signals when VOUT is within ±8.5% of the n Output Soft-Start and Tracking programmed output voltage as well as fault conditions. The n Small 10-Lead or 16-Lead MSOP Package LT8609A has slower switch edges for lower EMI emissions. The LT8609B operates in pulse-skipping mode only.
APPLICATIONS PULSE-SKIPPING MODE, Burst Mode OPERATION SWITCH EDGE SPEED
n GSM Transceivers LT8609 Both Fast n General Purpose Step-Down n Low EMI Step-Down LT8609A Both Medium All registered trademarks and trademarks are the property of their respective owners. LT8609B Pulse-Skipping Fast
TYPICAL APPLICATION 12VIN to 5VOUT Efficiency
100
5V, 2MHz Step-Down
95 V 90 IN VIN BST 5.5V TO 40V 4.7µF ON OFF 85 EN/UV 0.1µF 2.2µH VOUT SYNC SW 5V 80 10pF 2A LT8609 75 INTVCC 70 TR/SS PG 1M EFFICIENCY (%) RT FB 65 1µF 18.2k 187k 22µF GND 60 55 8609 TA01a fSW = 2MHz 50 0 0.50 1.00 1.50 2.00 2.50 IOUT (A) 8609 TA01b 8609fg For more information www.linear.com/LT8609 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
FEATURES DESCRIPTION
n
Wide Input Voltage Range: 3.0V to 42V
The LT®8609/LT8609A/LT8609B is a compact, high ef- n
Ultralow Quiescent Current Burst Mode® Operation:
ficiency, high speed synchronous monolithic step-down n
<2.5µA IQ Regulating 12VIN to 3.3VOUT
switching regulator that consumes only 1.7µA of non- n
Output Ripple <10mVP-P
switching quiescent current. The LT8609/LT8609A/LT8609B n
High Efficiency 2MHz Synchronous Operation:
can deliver 2A of continuous current with peak loads of n
>93% Efficiency at 1A, 5VOUT from 12VIN
3A (<1sec). Burst Mode operation enables high efficiency n
2A Maximum Continuous Output, 3A Peak
down to very low output currents while keeping the output
Transient Output
ripple below 10mVP-P. A SYNC pin allows synchronization to n
Fast Minimum Switch-On Time: 45ns
an external clock, or spread spectrum modulation for low EMI n
Adjustable and Synchronizable: 200kHz to 2.2MHz
operation. Internal compensation with peak current mode n
Spread Spectrum Frequency Modulation for Low EMI
topology allows the use of small inductors and results in fast n Allows Use of Small Inductors transient response and good loop stability. The EN/UV pin n Low Dropout has an accurate 1V threshold and can be used to program n Peak Current Mode Operation VIN UVLO or to shut down the part. A capacitor on the TR/SS n Accurate 1V Enable Pin Threshold pin programs the output voltage ramp rate during start-up n Internal Compensation while the PG flag signals when VOUT is within ±8.5% of the n Output Soft-Start and Tracking programmed output voltage as well as fault conditions. The n Small 10-Lead or 16-Lead MSOP Package LT8609A has slower switch edges for lower EMI emissions. The LT8609B operates in pulse-skipping mode only.
APPLICATIONS PULSE-SKIPPING MODE, Burst Mode OPERATION SWITCH EDGE SPEED
n GSM Transceivers LT8609 Both Fast n General Purpose Step-Down n Low EMI Step-Down LT8609A Both Medium All registered trademarks and trademarks are the property of their respective owners. LT8609B Pulse-Skipping Fast
TYPICAL APPLICATION 12VIN to 5VOUT Efficiency
100
5V, 2MHz Step-Down
95 V 90 IN VIN BST 5.5V TO 40V 4.7µF ON OFF 85 EN/UV 0.1µF 2.2µH VOUT SYNC SW 5V 80 10pF 2A LT8609 75 INTVCC 70 TR/SS PG 1M EFFICIENCY (%) RT FB 65 1µF 18.2k 187k 22µF GND 60 55 8609 TA01a fSW = 2MHz 50 0 0.50 1.00 1.50 2.00 2.50 IOUT (A) 8609 TA01b 8609fg For more information www.linear.com/LT8609 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
