Datasheet LTC3534 (Analog Devices) - 7
| Manufacturer | Analog Devices |
| Description | 7V, 500mA Synchronous Buck-Boost DC/DC Converter |
| Pages / Page | 20 / 7 — pin FuncTions. GND Pads (Pins 1, 8, 9, 16; GN Package):. VOUT (Pin 11):. … |
| File Format / Size | PDF / 468 Kb |
| Document Language | English |
pin FuncTions. GND Pads (Pins 1, 8, 9, 16; GN Package):. VOUT (Pin 11):. MUST. RUN/SS (Pin 2):. PVIN (Pin 12):. VIN (Pin 13):
Model Line for this Datasheet
Text Version of Document
LTC3534
pin FuncTions GND Pads (Pins 1, 8, 9, 16; GN Package):
IC Substrate
VOUT (Pin 11):
Output of the Synchronous Rectifier. A filter Grounds. These pins
MUST
be soldered to the printed capacitor is placed from VOUT to GND. A ceramic bypass circuit board ground to provide both electrical contact capacitor is recommended as close to the VOUT and GND and a good thermal contact to the PCB. pins as possible. VOUT is given by the following equation:
RUN/SS (Pin 2):
Combined Shutdown and Soft-Start. Ap- R1+R2 plying a voltage below 400mV shuts down the IC. Apply V V OUT = 1.000 • R2 a voltage above 1.4V to enable the IC and above 2.4V to ensure that the error amp is not clamped from soft-start.
PVIN (Pin 12):
Power VIN Supply Pin. A 10µF ceramic An R-C from the enable command signal to this pin will capacitor is recommended as close to the PVIN and PGND provide a soft-start function by limiting the rise time of pins as possible. the VC pin. PWM mode operation must be commanded
VIN (Pin 13):
Input Supply Pin. Connect the power source to properly enable the IC. to this pin.
GND (Pin 3):
Signal Ground for the IC.
VC (Pin 14):
Error Amp Output. An R-C network is con-
PGND1, PGND2 (Pins 4, 7):
Power Ground for the Internal nected from this pin to FB for loop compensation. Refer N-channel MOSFET Power Switches (Switches B and C). to “Closing the Feedback Loop” section for component selection guidelines.
SW1 (Pin 5):
Switch Pin where Internal Switches A and B are Connected. Connect inductor from SW1 to SW2.
FB (Pin 15):
Feedback Pin. Connect VOUT resistor divider Minimize trace length to reduce EMI. tap to this pin. The output voltage can be adjusted from 1.8V to 7V. The feedback reference voltage is typically 1V.
SW2 (Pin 6):
Switch Pin where Internal Switches C and D are Connected. Minimize trace length to reduce EMI.
Exposed Pad (Pin 17; DHC Package):
IC Substrate Ground. This pin
MUST
be soldered to the printed circuit board
PWM (Pin 10):
Burst Mode Select. PWM must be driven ground to provide both electrical contact and a good HIGH during start-up. When VOUT is in regulation, the thermal contact to the PCB. PWM pin may be driven LOW to command Burst Mode operation. Applying a voltage below 400mV enables Burst Mode operation, providing a significant efficiency improve- ment at light loads. Burst Mode operation will continue until this pin is driven high. Applying a voltage above 1.4V disables Burst Mode operation, enabling low noise, fixed frequency operation. 3534fb For more information www.linear.com/LTC3534 7 Document Outline Features Applications Description Typical Application 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 Related Parts
pin FuncTions GND Pads (Pins 1, 8, 9, 16; GN Package):
IC Substrate
VOUT (Pin 11):
Output of the Synchronous Rectifier. A filter Grounds. These pins
MUST
be soldered to the printed capacitor is placed from VOUT to GND. A ceramic bypass circuit board ground to provide both electrical contact capacitor is recommended as close to the VOUT and GND and a good thermal contact to the PCB. pins as possible. VOUT is given by the following equation:
RUN/SS (Pin 2):
Combined Shutdown and Soft-Start. Ap- R1+R2 plying a voltage below 400mV shuts down the IC. Apply V V OUT = 1.000 • R2 a voltage above 1.4V to enable the IC and above 2.4V to ensure that the error amp is not clamped from soft-start.
PVIN (Pin 12):
Power VIN Supply Pin. A 10µF ceramic An R-C from the enable command signal to this pin will capacitor is recommended as close to the PVIN and PGND provide a soft-start function by limiting the rise time of pins as possible. the VC pin. PWM mode operation must be commanded
VIN (Pin 13):
Input Supply Pin. Connect the power source to properly enable the IC. to this pin.
GND (Pin 3):
Signal Ground for the IC.
VC (Pin 14):
Error Amp Output. An R-C network is con-
PGND1, PGND2 (Pins 4, 7):
Power Ground for the Internal nected from this pin to FB for loop compensation. Refer N-channel MOSFET Power Switches (Switches B and C). to “Closing the Feedback Loop” section for component selection guidelines.
SW1 (Pin 5):
Switch Pin where Internal Switches A and B are Connected. Connect inductor from SW1 to SW2.
FB (Pin 15):
Feedback Pin. Connect VOUT resistor divider Minimize trace length to reduce EMI. tap to this pin. The output voltage can be adjusted from 1.8V to 7V. The feedback reference voltage is typically 1V.
SW2 (Pin 6):
Switch Pin where Internal Switches C and D are Connected. Minimize trace length to reduce EMI.
Exposed Pad (Pin 17; DHC Package):
IC Substrate Ground. This pin
MUST
be soldered to the printed circuit board
PWM (Pin 10):
Burst Mode Select. PWM must be driven ground to provide both electrical contact and a good HIGH during start-up. When VOUT is in regulation, the thermal contact to the PCB. PWM pin may be driven LOW to command Burst Mode operation. Applying a voltage below 400mV enables Burst Mode operation, providing a significant efficiency improve- ment at light loads. Burst Mode operation will continue until this pin is driven high. Applying a voltage above 1.4V disables Burst Mode operation, enabling low noise, fixed frequency operation. 3534fb For more information www.linear.com/LTC3534 7 Document Outline Features Applications Description Typical Application 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 Related Parts
