ADP1972ARUZ-R7 datasheet(16/18 Pages) AD

部件名	ADP1972ARUZ-R7

功能描述	Buck or Boost, PWM Controller for Battery Test Solutions

PDF	18 Pages

Scroll/Zoom	100%

制造商	AD [Analog Devices]

网页	http://www.analog.com

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16 / 18 page

ADP1972

Data Sheet

ADJUSTING THE SOFT START PERIOD

The ADP1972 has a programmable soft start feature that

prevents output voltage overshoot during startup. Refer to

Figure 18 for a soft start diagram. Use the following equation to

calculate the delay time before switching is enabled (tREG):

REG

= 0.52

(12)

where ISS = 5 µA, typical.

A CSS capacitor is not required for the ADP1972. When the CSS

capacitor is not used, the internal 5 µA (typical) current source

immediately pulls the SS pin voltage to VREG. When a CSS

capacitor is not used, there is no soft start control internal to the

ADP1972, and the system could produce a large output overshoot

and a large peak inductor spike during startup. When a CSS is

not used, ensure that the output overshoot is not large enough

to trip the hiccup current limit during startup.

Rev. B | Page 16 of 18

ADP1972ARUZ-R7 数据表(PDF) 16 Page - Analog Devices