www.fairchildsemi.com
REV. 1.0.6 1/22/02
Features
5.4V to 24V input voltage range
Five regulated outputs:
5V @ 5A (PWM)
3.3V @ 5A (PWM)
5V @ 50mA Always On (Linear)
12V/Adjustable @ 120mA Boost (PWM)
>96% efficiency
Hysteretic mode for light loads
PWM mode for normal loads
Main regulators switch out of phase
300kHz fixed frequency switching
RDS(ON) current sense over-current
Reduced BOM; Max. efficiency
Optional current sense resistor for precision over-current
detect
Power Good signal for all voltages
Input under-voltage lock-out (UVLO)
Thermal shutdown
ACPI compliant
24-pin TSSOP
Applications
Notebook PCs
Web tablets
Battery-powered instruments
Description
The FAN5233 is a high efficiency and high precision
multiple-output voltage regulator for notebook PC and other
similar battery-powered applications. It integrates three
pulse-width modulated (PWM) switching regulator
controllers and one linear regulator to convert 5.4V-to-24V
notebook battery power into the voltage used by the circuitry
that surrounds the microprocessor in these systems.
The two primary PWM controllers in the FAN5233 use
synchronous-mode rectification to provide 3.3V and 5V at
over 5A each. They switch out-of-phase to minimize input
ripple-current. Utilization of both input and output voltage
feedback in a current-mode control allows for fast and stable
loop response over a wide range of input and output
variations. PWM control in normal operation and hysteretic
control under light load provides efficiency of greater than
95% over a wide range of input and output variations. The
third PWM controller generates 12V at 120mA. A propri-
etary technology is used for sensing of output current using
the RDS(ON) of the external MOSFETs, eliminating exter-
nal current sense resistors which saves board space and
reduces BOM cost.
One integrated linear regulator provides stand-by
ALWAYS-ON power at 5V for light (50mA) loads.
Additional FAN5233 features include over-voltage, under-
voltage, and over-current monitors and thermal shutdown
protection. A single Power-Good signal is issued when soft
start is completed and all outputs are within 10% of their
settings.
FAN5233
System Electronics Regulator for Mobile PCs
FAN5233
PRODUCT SPECIFICATION
2
REV. 1.0.6 1/22/02
Pin Assignments
Pin Description
Pin Name
Pin Number Pin Function Description
VIN
1
Input power.
FPWM
2
Mode Control.
Taking this pin to +5V forces PWM mode of operation. Pull to
GND for normal operation. During Start-up FPWM pin should be forced high.
CPUMP3.3
3
Charge Pump 3.3V.
High side Gate drive voltage for 3.3V. This pin is to be
connected to SW3.3 through a 100nF cap. and to 5V-ALWAYS through a diode
HSD3.3
4
High-side gate driver for 3.3V.
Connect this pin directly to the gate of an
N-channel MOSFET. The trace from this pin to the MOSFET gate should be < 1".
SW3.3
5
High side FET Source and Low Side FET Drain Switching Node.
Switching
node for 3.3V.
5V-ALWAYS
6
5V Always on linear regulator output.
This pin should be decoupled to ground
with a 10F capacitor.
1
Top View
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
VIN
FPWM
5V-ALWAYS
CPUMP3.3
HSD3.3
SW3.3
ISEN3.3
LSD3.3
GND3.3
VFB3.3
SDN3.3
PGOOD
CPUMP5
HSD5
SW5
ISEN5
LSD5
GND5
VFB5
SDN5
SW12
VFB12
SGND
SDWN
Typical Application
1 VIN
2 FPWM
3 CPUMP3.3
4 HSD3.3
5 SW3.3
6 5V-ALW
7 LSD3.3
8 GND3.3
9 ISEN3.3
10 VFB3.3
11 SDN3.3
12 PGOOD
CPUMP5 24
HSD5 23
SW5 22
ISEN5 21
LSD5 20
GND5 19
VFB5 18
SDN5 17
SW12 16
VFB12 15
SGND 14
SDWN 13
FAN5233
Vin = 5.4-24V
12V @ 120mA
5V @ 5A
SDN5
SDWN
PGOOD
3.3V @ 5A
+
SDN3.3
+
+
5V-ALWAYS@ 50mA
5V-ALWAYS
5V-ALWAYS
VFB12
PRODUCT SPECIFICATION
FAN5233
REV. 1.0.6 1/22/02
3
LSD3.3
7
Low-side gate driver for 3.3V.
Connect this pin directly to the gate of an
N-channel MOSFET. The trace from this pin to the MOSFET gate should be < 1".
GND3.3
8
Ground for 3.3V MOSFET.
ISEN3.3
9
Current sense for 3.3V.
This pin should be connected to the Drain of the bottom
Mosfet with an appropriate resistor and an RC filter. See Application Section.
VFB3.3
10
Voltage feedback for 3.3V.
SDN3.3
11
Soft Start and ON/OFF for 3.3V.
OFF=GND. ON=open with SDWN=High. Use
open collector device for control.
PGOOD
12
Power Good Flag.
An open collector output that will be logic low if any output
voltage is not above 89% of the nominal output voltage.
SDWN
13
Master Shutdown.
Shutdown for all power. Off when low. When high
5V/3.3V-ALWAYS are ON while 5V/3.3V-Main are ready to turn on if SDN5,
SDN3.3 go open.
SGND
14
Signal ground.
VFB12
15
Voltage feedback for 12V.
SW12
16
FET driver for 12V Boost.
SDN5
17
Enable/Soft Start for 5V and 12V.
Soft start and ON/OFF for 5V & 12V.
OFF=Grounded. ON=open with SDWN=High.
VFB5
18
Voltage feedback for 5V.
GND5
19
Ground for 5V MOSFET.
LSD5
20
Low side FET driver for 5V.
Connect this pin directly to the gate of an N-channel
MOSFET. The trace from this pin to the MOSFET gate should be < 1".
ISEN5
21
Current Sense for 5V.
This pin should be connected to the drain of the bottom
Mosfet using appropriate resistor and RC filter. See Application Section.
SW5
22
High Side Driver Source and Low Side Driver Drain Switching Node.
Switching node for 5V.
HSD5
23
High side FET driver for 5V.
Connect this pin directly to the gate of an N-channel
MOSFET. The trace from this pin to the MOSFET gate should be < 1".
CPUMP5
24
Charge Pump 5V.
High side Gate drive voltage for 5V. High side Gate drive
voltage for 5V. This pin is to be connected to SW5 through a 100nF cap. and to
5V-ALWAYS through a diode.
Pin Description
(Continued)
Pin Name
Pin Number Pin Function Description
FAN5233
PRODUCT SPECIFICATION
4
REV. 1.0.6 1/22/02
Absolute Maximum Ratings
1
Note:
1. Stresses beyond "Absolute Maximum Ratings" may cause permanent device damage. Continuous exposure to absolute
maximum rating conditions may affect device reliability. Functional operation of the device at these or any other conditions
beyond those indicated in the operational sections of the specification is not implied.
Recommended Operating Conditions
Thermal Information
ELECTRICAL SPECIFICATIONS
Parameter
Conditions
Min.
Typ.
Max.
Units
V
IN
-0.3
27
V
SW, ISEN Pins,SDWN Pin
-0.3
27
V
CPUMP, HSD Pins
-0.3
33
V
SDN, VFB, V_always pins
-0.3
6.5
V
CPUMP to SW pins, and all other pins
-0.3
6.5
V
I
LOAD
5V-Always
60
mA
Input Voltage, V
IN
+5.4V to 24V
Ambient Temperature, T
A
-20C to 85C
Thermal Resistance, RTH
JA
88C/W
Thermal Resistance, RTH
JC
16C/W
Maximum Junction Temperature
150C
Storage Temperature Range
-65C to 150C
Maximum Lead Temperature, Soldering 10 Sec
300C
Operating Conditions
Recommended Operating Conditions Unless Noted Refers to Block Diagrams
Parameter
Conditions
Min.
Typ.
Max.
Units
Supply
V
IN
Input Supply Voltage
(DC loading only) Note 1
5.4
24
V
Input Quiescent Current
H/LSD Open
1.4
3
mA
Stand-by
300
400
A
Shut-down
<1
5
A
Input UVLO Threshold
Rising Vbat
4.3
4.7
5.1
V
hysteresis
100
mV
5V and 3.3V Main Regulators
Output Voltage Precision
0.1 to 5.5A, 5.4 to 24V
-2
+2
%
Oscillator Frequency, f
osc
255
300
345
kHz
HSD On-Resistance, pull up
7
12
HSD On Resistance pull down
4
10
LSD On-Resistance, pull up
6
9
PRODUCT SPECIFICATION
FAN5233
REV. 1.0.6 1/22/02
5
LSD On Resistance pull down
5
8
HSD On Output, V
CPUMP
-V
GS
I = 10A
100
mV
HSD Off Output, V
GS
I = 10A
100
mV
LSD On Output, V
5V-Always
-V
GS
I = 10A
100
mV
LSD Off Output, V
GS
I = 10A
100
mV
Ramp Amplitude, pk-pk
VIN = 16V
2
V
Ramp Offset
0.5
V
Ramp Gain from V
IN
125
mV/V
Error Amplifier GBW
3
MHz
Current Limit Threshold
R2, R8 = 1K
90
135
180
A
Over Voltage Threshold
2s delay
110
115
120
%VO
Under Voltage Threshold
2s delay
70
75
80
%VO
SDN/SS Full On Voltage Min.
(End of Soft Start)
4.2
V
SDN/SS Full Off Voltage Max.
800
mV
Max Duty Cycle
94
%
Min PWM Time
200
nsec
VFB3.3 Input Leakage Current
40
55
70
A
12V Regulator
Output Voltage Precision
V_5 =4.9 to 5.1V
and Io=0 to 150mA
-2
+2
%
V
FB12
2.472
V
V
FB12
Input Current
Note 2
100
200
nA
Oscillator Frequency (f
osc
/3)
85
100
115
kHz
Gate Drive On-Resistance
High or Low
6
12
On Output, V
5V-Always
-V
GS
I = 10A
100
mV
Off Output, V
GS
I = 10A
100
mV
Ramp Amplitude, pk-pk
2
V
Error Amplifier GBW
1
MHz
Under Voltage Shut Down
2s delay
70
76
80
%V
O
Over Voltage Shut Down
Measured at VFB
12
115
%V
O
Min Duty Cycle
0
%
Max Duty Cycle
(By design)
32
33
34
%
5V Always
Bypass Switch rdson
1.3
1.5
Linear Regulator Accuracy
5.6 to 24V, 0 to 50mA,
5V Main On or Off
-3.3
2
%
Rated Output Current
I
5
0
50
mA
Over-current Limit
2s delay
100
180
mA
Under-voltage Threshold
2s delay
70
75
80
%
Reference
Internal Reference Accuracy
0-70C
-1
1
%
Operating Conditions
(Continued)
Recommended Operating Conditions Unless Noted Refers to Block Diagrams
Parameter
Conditions
Min.
Typ.
Max.
Units
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