HIP6501ACBZ datasheet(12/14 Pages) RENESAS

12 / 14 page

HIP6501A

FN4749 Rev 6.00

Page 12 of 14

December 30, 2004

If a P-Channel MOSFET is used to switch the 5VSB output

of the ATX supply into the 5VDUAL output during S3 and

S4/S5 states (as dictated by EN5VDL status), then, similar to

the situation where Q1 is a MOSFET, the selection criteria of

this device is also proper voltage budgeting. The maximum

rDS(ON), however, has to be achieved with only 4.5V of VGS,

so a logic level MOSFET needs to be selected. If a PNP

device is chosen to perform this function, it has to have a low

saturation voltage while providing the maximum sleep-state

current and have a current gain sufficiently high to be

saturated using the minimum drive current (typically 20mA;

4mA during soft-start).

Q3, Q5

The two N-Channel MOSFETs are used to switch the 3.3V

and 5V inputs provided by the ATX supply into the

3.3VDUAL and 5VDUAL outputs, respectively, while in

active (S0, S1) states. Similar rDS(ON) criteria apply in these

cases as well, unlike the PMOS, however, these NMOS

transistors get the benefit of an increased VGS drive

(approximately 8V and 7V, respectively).

The NPN transistor used as sleep-state pass element on the

3.3VDUAL output must have a minimum current gain of 100

at VCE = 1.5V, and ICE = 500mA throughout the in-circuit

operating temperature range.

HIP6501ACBZ bảng dữ liệu(PDF) 12 Page - Renesas Technology Corp