Datasheet LTC3546 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Dual Synchronous, 3A/1A or 2A/2A Configurable Step-Down DC/DC Regulator |
| Pages / Page | 30 / 1 — FEATURES. DESCRIPTION. VIN Range: 2.3V to 5.5V. VOUT Range: 0.6V to 5V. … |
| File Format / Size | PDF / 624 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. VIN Range: 2.3V to 5.5V. VOUT Range: 0.6V to 5V. Programmable Frequency Operation; 2.25MHz, or
Model Line for this Datasheet
Text Version of Document
LTC3546 Dual Synchronous, 3A/1A or 2A/2A Configurable Step-Down DC/DC Regulator
FEATURES DESCRIPTION
n
VIN Range: 2.3V to 5.5V
The LTC®3546 is a dual, constant-frequency, synchronous n
VOUT Range: 0.6V to 5V
step down DC/DC converter for medium power applications. n
Programmable Frequency Operation; 2.25MHz, or
The design consists of 2A and 1A primary output switches.
Adjustable Between 0.75MHz to 4MHz
In addition to the 2A/1A capability, a 1A dependant output n
Low RDS(ON) Internal Switches
switch can be externally connected to either of the primary n
High Efficiency: Up to 96%
outputs to produce 3A/1A dual regulator or 2A/2A dual n No Schottky Diodes Required regulator configurations. n Short-Circuit Protected Supply operation is from 2.3V to 5.5V. The switching fre- n Current Mode Operation for Excellent Line and Load quency can be set to 2.25MHz, adjustable from 0.75MHz Transient Response to 4MHz, or synchronized to an external clock. Each n Low Ripple Burst Mode Operation (30mVP-P), output is adjustable from 0.6V to 5V and has output IQ = 160µA tracking on power-up. Internal synchronous low R n DS(ON) Ultralow Shutdown Current: IQ < 1µA power switches provide high efficiency without external n Low Dropout Operation: 100% Duty Cycle Schottky diodes. n Power Good Output For Each Channel n Externally or Internally Programmable Burst Level User-selectable modes (Burst Mode® operation, pulse n External or Internal Soft-Start or Supply Tracking skipping and forced continuous) allow a trade-off between n Available in Thermally Enhanced 28-Lead ripple noise and power efficiency. Burst Mode operation (4mm × 5mm) QFN and TSSOP Packages provides high efficiency at light loads. Pulse-skipping mode provides low ripple noise at light loads.
APPLICATIONS
The device is capable of low dropout configurations and both channels can operate at 100% duty cycle. In shut- n Netbooks/Ultra-Mobile PCs down, the device draws <1µA. n PC Cards All registered trademarks and trademarks are the property of their respective owners. Protected n Wireless and DSL Modems by U.S. Patents, including 5481178, 6611131, 6304066, 6498466, 6580258. n Point of Load DC/DC Conversion
TYPICAL APPLICATION
VIN
V
3.6V TO CIN
OUT2 Efficiency (Burst Mode Operation)
V 22µF IN1 VCCA VCCD VIN2 5.5V 100 100 SYNC/MODE SW1D CONNECTED TO SW2 0.56µH PGOOD2 PGOOD1 1.22µH VIN = 3.6V VOUT2 VOUT1 95 V SW2A SW1 OUT = 2.5V 10 2.5V, 3A 1.2V, 1A SW2B 100pF 100pF POWER LOSS (W) 90 SW1D EFFICIENCY 1 VIN RUN2 LTC3546 RUN1 VIN 68µF 22µF 85 0.1 VFB2 VFB1 95.3k 30.1k 30.1k VIN BMC2 BMC1 30.1k EFFICIENCY (%) 80 0.01 TRACK/SS2 TRACK/SS1 VIN POWER LOSS PHASE FREQ 75 0.001 ITH2 ITH1 13k 13k 10pF PGND2 GNDA PGND1 10pF 70 0.0001 1000pF 1000pF 0.001 0.01 0.1 1 10 3546 TA01a LOAD CURRENT (A) 3546 TA01b EXPOSED PAD 3546fd For more information www.linear.com/3546 1
FEATURES DESCRIPTION
n
VIN Range: 2.3V to 5.5V
The LTC®3546 is a dual, constant-frequency, synchronous n
VOUT Range: 0.6V to 5V
step down DC/DC converter for medium power applications. n
Programmable Frequency Operation; 2.25MHz, or
The design consists of 2A and 1A primary output switches.
Adjustable Between 0.75MHz to 4MHz
In addition to the 2A/1A capability, a 1A dependant output n
Low RDS(ON) Internal Switches
switch can be externally connected to either of the primary n
High Efficiency: Up to 96%
outputs to produce 3A/1A dual regulator or 2A/2A dual n No Schottky Diodes Required regulator configurations. n Short-Circuit Protected Supply operation is from 2.3V to 5.5V. The switching fre- n Current Mode Operation for Excellent Line and Load quency can be set to 2.25MHz, adjustable from 0.75MHz Transient Response to 4MHz, or synchronized to an external clock. Each n Low Ripple Burst Mode Operation (30mVP-P), output is adjustable from 0.6V to 5V and has output IQ = 160µA tracking on power-up. Internal synchronous low R n DS(ON) Ultralow Shutdown Current: IQ < 1µA power switches provide high efficiency without external n Low Dropout Operation: 100% Duty Cycle Schottky diodes. n Power Good Output For Each Channel n Externally or Internally Programmable Burst Level User-selectable modes (Burst Mode® operation, pulse n External or Internal Soft-Start or Supply Tracking skipping and forced continuous) allow a trade-off between n Available in Thermally Enhanced 28-Lead ripple noise and power efficiency. Burst Mode operation (4mm × 5mm) QFN and TSSOP Packages provides high efficiency at light loads. Pulse-skipping mode provides low ripple noise at light loads.
APPLICATIONS
The device is capable of low dropout configurations and both channels can operate at 100% duty cycle. In shut- n Netbooks/Ultra-Mobile PCs down, the device draws <1µA. n PC Cards All registered trademarks and trademarks are the property of their respective owners. Protected n Wireless and DSL Modems by U.S. Patents, including 5481178, 6611131, 6304066, 6498466, 6580258. n Point of Load DC/DC Conversion
TYPICAL APPLICATION
VIN
V
3.6V TO CIN
OUT2 Efficiency (Burst Mode Operation)
V 22µF IN1 VCCA VCCD VIN2 5.5V 100 100 SYNC/MODE SW1D CONNECTED TO SW2 0.56µH PGOOD2 PGOOD1 1.22µH VIN = 3.6V VOUT2 VOUT1 95 V SW2A SW1 OUT = 2.5V 10 2.5V, 3A 1.2V, 1A SW2B 100pF 100pF POWER LOSS (W) 90 SW1D EFFICIENCY 1 VIN RUN2 LTC3546 RUN1 VIN 68µF 22µF 85 0.1 VFB2 VFB1 95.3k 30.1k 30.1k VIN BMC2 BMC1 30.1k EFFICIENCY (%) 80 0.01 TRACK/SS2 TRACK/SS1 VIN POWER LOSS PHASE FREQ 75 0.001 ITH2 ITH1 13k 13k 10pF PGND2 GNDA PGND1 10pF 70 0.0001 1000pF 1000pF 0.001 0.01 0.1 1 10 3546 TA01a LOAD CURRENT (A) 3546 TA01b EXPOSED PAD 3546fd For more information www.linear.com/3546 1
