MC33567D-3R2 ON Semiconductor, MC33567D-3R2 Datasheet - Page 4

• Manufacturer Part Number: MC33567D-3R2
• Manufacturer: ON Semiconductor

Specifications of MC33567D-3R2

• Lead Free Status / RoHS Status: Not Compliant

Introduction
Controllers designed for Power Management applications
where high current, voltage regulation is needed. Some
computer applications include:
(V out ), and incorporates individual SHDN controls for each
FET controller and voltage protection by sensing the output
voltage.
Output:
from one or two supply voltages using 2 external N−Channel
MOSFETs. Each controller operates independently and
regulates the output voltage to a predetermined level (1.2 V,
1.515 V 1.818 V, 2.3 V or 2.525 V). In addition, regulator 2
of the MC33567−1 incorporates a V in bypass mode on which
the external FET is fully enhanced.
Shutdown:
with the use of the SHDN pin. It also determines the output
voltage level. SHDN can be controlled externally from
board signals like the AGP or GTL+ as shown in Figure 3.
Card Type
Detection
The MC33567 series is a family of Dual Linear FET
The MC33567 provides tight output voltage regulation,
The MC33567 provides tight output voltage regulation
The regulated outputs of the MC33567 can be disabled
(Gunning Transistor Logic − Intel’s electrical bus
technology)
1.2 V − Power Supply
1.515 V − AGP (Advanced Graphic Port) and GTL+
1.818 V − I/O planes on motherboards
2.3 V − Power Supply
2.525 V − Clock and memory
AGP
1
2
3
4
Figure 3. 1.5 V/3.3 V AGP Card Detection
*V in while on bypass mode (MC33567−1 only)
MC33567
3.3 V
12 V (V CC )
8
7
6
5
DRV2
SENSE2
SHDN2
10 kW
3.3 V (V in )
OPERATING DESCRIPTION
V out or V in *
Voltage
AGP
Card
http://onsemi.com
MC33567
4
the corresponding regulator output voltages:
Table 1. Logic Table for SHDN Pin
Undervoltage Detection:
greater than 250 s or a short circuit condition is present, that
output will go into short circuit or Hiccup Mode. While in
Hiccup mode, the output is turned ON for 1.0 ms and OFF
for 40 ms for a duty cycle of 1:41 as shown in Figure 4. This
mode will continue as long as the fault is present. Once the
fault is removed, the regulator will resume normal
operation.
relationship with V SHDN .
MC33567−1
MC33567−2
MC33567−3
Listed below are the SHDN threshold voltage levels and
If V out drops below 75% of the regulated threshold for
1. If the SHDN pin is left open, the output voltage is set
2. If a voltage less than 0.8 V is applied to the SHDN pin,
3. If a voltage greater than 1.3 V and less than 4.1 V is
4. If the SHDN voltage is pulled above 4.1 V, the
Table 1 summarizes the output voltage options and its
REGULATOR 1
REGULATOR 2
REGULATOR 1 &
REGULATOR 2
REGULATOR 1
REGULATOR 2
1 ms
to its regulated value.
the output voltage is set to 0 V.
applied to the SHDN pin, the output voltage is set to its
regulated voltage.
MC33567 enters a V in bypass mode. In this mode, the
MOSFET is fully enhanced and the output voltage is
the MOSFET drain voltage (V in ) minus the MOSFET
drain−source on voltage V DS(on) . This feature is only
available on REGULATOR 2 of the MC33567−1.
Device
Figure 4. Hiccup Mode Duty Cycle
1.3 V t V SHDN t 4.1 V
40 ms
V SHDN (V)
No Connect
No Connect
No Connect
No Connect
No Connect
u 4.1 V
u 1.3 V
t0.8 V
u1.3 V
t0.8 V
t0.8 V
u1.3 V
t0.8 V
u1.3 V
t0.8 V
V in −V DS(on)
(Bypass Mode)
V out (V)
1.818 V
1.818 V
1.515 V
1.515 V
2.525 V
2.525 V
2.3 V
2.3 V
1.2 V
1.2 V
0 V
0 V
0 V
0 V
0 V