特点
V
OUT
= 1/2 V
IN
(Supply Splitter)
Adjustable and Symmetrical Sink/Source Current Limit up to 20A
±0.65% Output Voltage Accuracy
Up to 97% Efficiency
No Sense Resistor Required
Ultrafast Transient Response
True Current Mode Control
2% to 90% Duty Cycle at 200kHz
t
ON(MIN)
Stable with Ceramic C
OUT
Dual N-Channel MOSFET Synchronous Drive
Power Good Output Voltage Monitor
Wide V
CC
Range: 4V to 36V
Adjustable Switching Frequency up to 1.5MHz
Output Overvoltage Protection
Optional Short-Circuit Shutdown Timer
Available in a 16-Pin Narrow SSOP Package
典型应用
典型应用
描述
The LTC?3717 is a synchronous step-down switching regulator controller for double data rate (DDR) and Quad Data Rate? (QDR?) memory termination. The controller uses a valley current control architecture to deliver very low duty cycles without requiring a sense resistor. Operating frequency is selected by an external resistor and is compensated for variations in V IN .
Forced continuous operation reduces noise and RF interference. Output voltage is internally set to half of V REF , which is user programmable.
Fault protection is provided by an output overvoltage comparator and optional short-circuit shutdown timer. Soft-start capability for supply sequencing is accomplished using an external timing capacitor. The regulator current limit level is symmetrical and user programmable. Wide supply range allows operation from 4V to 36V at the V CC input.