RICHTEK RT9227A-CS

RT9227A
Preliminary
Advanced PWM and Dual Fixed Linear Power Controller
General Description
Features
The RT9227A is a 3-in-one power controller
z
3-in-one Regulated Voltages for Microprocessor
Core, Clock, and GTL
optimized for high-performance microprocessor and
a
z
Compatible with HIP6016
synchronous buck PWM controller, a linear regulator
z
Power-good Output Voltage Monitor
computer
applications.
The
IC
integrates
and a linear controller as well as monitoring and
Switching section
protection functions into a 24-pin SOP package. The
5-bit DAC Programmable from 1.3V to 3.5V
PWM controller regulates the microprocessor core
z
voltage. The linear regulator provides power for the
z
clock driver circuit and the linear controller regulates
z
±1% DAC Accuracy
Fast Transient Response
power for the GTL bus.
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Full 0% to 100% Duty Cycle Driver
z
Fixed 200kHz Switching Frequency
The RT9227A features an Intel-compatible, TTL 5-bit
z
Adaptive Non-overlapping Gate Driver
programmable DAC that adjusts the core voltage
z
Over-current Monitor Uses MOSFET RDS(ON)
from 2.1V to 3.5V in 0.1V increments and from 1.3V
z
Over-voltage Protection Uses Lower MOSFET
to 2.05V in 0.05V steps. The 5-bit DAC has a typical
Linear Section
±1% tolerance. The linear regulator uses an internal
drive device to provide a fixed 2.5V ±2.5% output
z
Fixed Linear Regulator Output Voltage
voltage. The linear controller drives an external N-
z
MOSFET or NPN Driving Capability
channel MOSFET or a low cost NPN bipolar
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Ultra Fast Response Speed
transistor to provide a fixed 1.5V ±2.5%.
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Under-voltage Protection
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Internal Thermal Shutdown
The RT9227A monitors all the output voltages. A
Power-good signal is issued when the core voltage is
Applications
within ±10% of the DAC setting and the other levels
z
Full Motherboard Power Regulation for Computer
are above their under-voltage levels. Additional build-
z
Low-voltage Distributed Power Supplies
in over-voltage protection for the core output uses
the lower MOSFET to prevent output voltage above
115% of the DAC setting. The PWM over-current
function monitors the output current using the voltage
drop across the upper MOSFET’s RDS(ON), which
eliminates the need for a current sensing resistor.
Ordering Information
RT9227A… …
Package type
S : SOP-24
Operating temperature range
C: Commercial standard
DS9227A-02 July 2001
Pin Configurations
Part Number
RT9227ACS
(Plastic SOP-24)
Pin Configurations
TOP VIEW
VCC
VID4
VID3
1
24
2
23
3
UGATE1
PHASE1
22 LGATE1
VID2
4
21
VID1
VID0
PGOOD
FAULT
SS
NC
FB2
VIN2
5
20
6
19
7
18
8
NC
FB3
15 GATE3
14 GND
13 VOT2
9
10
11
12
PGND
OCSET1
VSEN1
FB1
17
16
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1
RT9227A
Preliminary
Absolute Maximum Ratings
z
Supply Voltage
+15V
z
PGOOD and GATE Voltage
GND−0.3V to VCC+0.3V
z
Input, Output or I/O Voltage
GND− 0.3V to 7V
z
Ambient Temperature Range
0°C to +70°C
z
Junction Temperature Range
0°C to +125°C
z
Storage Temperature Range
-65°C to +150°C
z
Lead Temperature (Soldering, 10 sec.)
300°C
z
Package Thermal Resistance
SOP-24,θJA
75°C/W
Recommended Operating Conditions
z
Supply Voltage
+12V±10%
z
Ambient Temperature Range
0°C to 70°C
z
Junction Temperature Range
0°C to 125°C
CAUTION:
Stresses beyond the ratings specified in “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress only rating and operation of the device at these or any other conditions above those
indicated in the operational sections of this specification is not implied.
Electrical Characteristics
(VCC = 12V, PGND = 0V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
UGATE1, GATE3, LGATE1,
and VOUT2 Open
--
10
--
mA
VCC Supply Current
Nominal Supply Current
ICC
Power-On Reset
VCC Rising Threshold
VOCSET1 = 4.5V
7.5
--
9.5
V
VCC Falling Threshold
VOCSET1 = 4.5V
7
--
9
V
Rising VIN2 Under-Voltage Threshold
--
--
2.8
V
VIN2 Under-Voltage Hysteresis
--
0.5
--
V
Rising VOCSET1 Threshold
--
1.25
--
V
180
200
225
KHz
--
1.9
--
VP-P
DAC (VID0 – VID4) Input Low Voltage
--
--
0.8
V
DAC (VID0 – VID4) Input High Voltage
2.0
--
--
V
Oscillator
Free Running Frequency
Ramp Amplitude
∆VOSC
Reference and DAC
DACOUT Voltage Accuracy
DACOUT = 2.05 ~ 3.50V
-1
--
1
%
DACOUT Voltage Accuracy
DACOUT = 1.30 ~ 2.00V
-1%
--
20mV
--
To be continued
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DS9227A-02 July 2001
RT9227A
Preliminary
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
2.437
2.500
2.563
V
--
1.875
2.175
V
--
100
--
mV
180
230
--
mA
--
700
--
mA
1.462
1.500
1.538
V
--
1.125
1.305
V
--
100
--
mV
--
65
--
dB
--
3
7
Ω
--
3
7
Ω
--
1
--
A
--
2
6
Ω
Linear Regulator
Regulation Voltage
VREG
Under-Voltage Level
10mA < IVOUT2 < 150mA
FB2 Rising
Under-Voltage Hysteresis
Over-Current Protection
Over-Current Protection During Start-Up
Linear Controller
Regulation Voltage
VREG
Under-Voltage Level
VSEN3 = GATE3
0 < IGATE3 < 20mA
FB3 Rising
Under-Voltage Hysteresis
PWM Controller Error Amplifier
DC Gain
PWM Controller Gate Driver
VCC = 12V
VCC - VUGATE1 = 1V
UGATE Source
RUGATE1
UGATE Sink
RUGATE1 VUGATE1 = 1V
LGATE Source
ILGATE1
LGATE Sink
RLGATE1 VLGATE1 = 1V
VCC = 12V, VLGATE1 = 2V
Protection
VOUT1 Over-Voltage Trip
VSEN1 Rising
112
115
120
%
FAULT Souring Current
VFAULT = 8V
10
14
--
mA
170
200
230
µA
--
11
--
µA
OCSET1 Current Source
IOCSET
VOCSET1 = 4.5V
Soft-Start Current
ISS
VSS = 1V
Power Good
VOUT1 Upper Threshold
VSEN1 Rising
108
--
112
%
VOUT1 Under Voltage
VSEN1 Rising
89
--
95
%
VOUT1 Hysteresis (VSEN1 / DACOUT)
Upper/Lower Threshold
--
2
--
%
--
--
0.5
V
PGOOD Voltage Low
DS9227A-02 July 2001
VPGOOD IPGOOD = -4mA
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3
RT9227A
Preliminary
Function Block Diagram
VSEN1
VCC
OCSET1
200µA
+
3.3V
+
+
90%
_
+
+
LINEAR
UNDER
VOLTAGE
115%
UGATE1
+
VOUT2
_
1.26V
_
PGOOD
VCC
+
LUV
FB2
_
OC2
+
SOFT-START
& FAULT
LOGIC
_
0.25A
UPPER
DRIVE
0V
OC1
+
VIN2
110%
0.3V
3.3V
_
_
GATE3
POWER-ON
RESET (POR)
_
VSEN3
_
FAULT
5V
_
TTL D/A
CONVERTER
(DAC)
ERROR
AMP
_
DACOUT
11µA
+
+
VCC
INHIBIT
GATE
CONTROL
PWM LOGIC
PWM COMP
OSCILLATOR
PHASE1
VCC
LGATE1
LOWER
DRIVE
PGND
GND
COMPENSATION
SS VID0 VID2 VID4
VID1 VID3
FB1
Functional Pin Description
VCC (Pin 1)
Provide a 12V bias supply for the IC to this pin. This
pin also provides the gate bias charge for all the
MOSFETs controlled by the IC.
VID0, VID1, VID2, VID3, VID4 (Pin 6, 5, 4, 3, and 2)
VIDO-4 are the input pins to the 5-bit DAC. The
states of these five pins program the internal voltage
reference, DACOUT. The level of DACOUT sets the
core converter output voltage. It also sets the core
PGOOD and OVP thresholds. Table 1 specifies the
DACOUT voltage of 32 combinations of VID levels.
PGOOD (Pin 7)
PGOOD is an open collector output used to indicate
the status of the output voltage. This pin is pulled low
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4
when the core output is not within ±10% of the
DACOUT reference voltage and the other outputs are
below their under-voltage thresholds.
The PGOOD output is open for ‘11111’ VID codes
that inhibit operation. See table 1.
FAULT (Pin 8)
This pin is low during normal operation, but it is
pulled to about 8V (VCC = 12V) in the event of an
over-voltage or over-current condition.
SS (Pin 9)
Connect a capacitor from this pin to ground. This
capacitor, along with an internal 11µA (VSS >1V)
current source, sets the soft-start interval of the
converter.
DS9227A-02 July 2001
RT9227A
Preliminary
FB2 (Pin 11)
Connect this pin to VOUT2 to set the linear regulator
converter over-current (OC) trip point according to
output voltage.
the following equation:
VIN2 (Pin 12)
IPEAK =
This pin supplies power to the internal regulator.
IOCSET1×ROCSET1
RDS(ON)
Connect this pin to a suitable 3.3V source.
PGND (Pin 21)
Additionally, this pin is used to monitor the 3.3V
This is the power ground of UGATE1 and LGATE1.
supply. If, following a startup cycle, the voltage drops
Tie the PWM converter’s lower MOSFET source to
below 2.55V (typically), the chip shuts down. A new
this pin.
soft-start cycle is initiated upon return of the 3.3V
supply above the under-voltage threshold.
LGATE1 (Pin 22)
Connect LGATE1 to the PWM converter’s lower
VOUT2 (Pin 13)
MOSFET gate. This pin provides the gate drive for
Output of the linear regulator. Supplies current up to
the lower MOSFET.
230mA.
GND (Pin 14)
Signal ground for the IC. All voltage levels are
measured with respect to this pin.
GATE3 (Pin 15)
Connect this pin to the gate of an external MOSFET
or the base of an NPN. This pin provides the drive for
the linear controller’s pass transistor.
FB3 (Pin 16)
Connect this pin to VOUT3 to set the linear controller
output voltage.
An over-current trip cycles the soft-start function.
Sustaining an over-current for 2 soft-start intervals
shuts down the controller.
PHASE1 (Pin 23)
Connect the PHASE1 pin to the PWM converter’s
upper MOSFET source. This pin is used to monitor
the voltage drop across the upper MOSFET for overcurrent protection.
UGATE1 (Pin 24)
Connect UGATE pin to the PWM converter’s upper
MOSFET gate. This pin provides the gate drive for
the upper MOSFET.
FB (Pin 18)
The FB1 pin is the inverting input of the error
amplifier.
VSEN1 (Pin 19)
This pin is connected to the PWM converter’s output
voltage. The PGOOD and OVP comparator circuits
use this signal to report output voltage status and for
over voltage protection.
OCSET1 (Pin 20)
Connect a resistor (ROCSET1) from this pin to the
drain of the upper MOSFET. ROCSET1, an internal
200µA current source (IOCSET1), and the upper
MOSFET on-resistance (RDS(ON)) set the PWM
DS9227A-02 July 2001
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5
RT9227A
Preliminary
Table 1. VOUT1 Voltage Program
Pin Name
VID4
VID3
VID2
VID1
VID0
Normal OUT1 Voltage
DACOUT
0
1
1
1
1
1.30
0
1
1
1
0
1.35
0
1
1
0
1
1.40
0
1
1
0
0
1.45
0
1
0
1
1
1.50
0
1
0
1
0
1.55
0
1
0
0
1
1.60
0
1
0
0
0
1.65
0
0
1
1
1
1.70
0
0
1
1
0
1.75
0
0
1
0
1
1.80
0
0
1
0
0
1.85
0
0
0
1
1
1.90
0
0
0
1
0
1.95
0
0
0
0
1
2.00
0
0
0
0
0
2.05
1
1
1
1
1
INHIBIT
1
1
1
1
0
2.10
1
1
1
0
1
2.20
1
1
1
0
0
2.30
1
1
0
1
1
2.40
1
1
0
1
0
2.50
1
1
0
0
1
2.60
1
1
0
0
0
2.70
1
0
1
1
1
2.80
1
0
1
1
0
2.90
1
0
1
0
1
3.00
1
0
1
0
0
3.10
1
0
0
1
1
3.30
1
0
0
1
0
3.30
1
0
0
0
1
3.40
1
0
0
0
0
3.50
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DS9227A-02 July 2001
RT9227A
Preliminary
Typical Application Circuit
12V
5V
L1
F1
1µH
15A
C1-4
4x1000µF
GND
+
R1
10
C5-6
2x1µF
C7
C20
1µF
1000pF
1
R2
VCC
20
OCSET1
1.21k
12
3.3V
+
C8
1000µF
Q3
RFD3055
V OUT3
1.5V
15
16
+ C9
1000µF
V OUT2
2.5V
VIN2
PGOOD
GATE3
FB3
UGATE1
PHASE1
RT9227A
13
11
VOUT2
LGATE1
PGND
FB2
+ C10
270µF
VSEN1
6 VID0
5
VID1
4
VID2
3
VID3
2 VID4
FB1
FAULT
GND
14
DS9227A-02 July 2001
SS
POWERGOOD
7
24
23
22
21
Q1
PHB83N03LT
R3
10K
L2
PHB95N03LT 3.5µH C13-19
Q2
7x1000µF
R4
4.99K
+
V OUT1
1.3 to 3.5V
19
C11
18
R5 0.68µF
732K
8
9
C12
0.039µF
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7
RT9227A
Preliminary
Package Information
H
M
B
B
J
A
C
F
Symbol
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8
D
I
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
15.189
15.596
0.598
0.614
B
7.391
7.595
0.291
0.299
C
2.362
2.642
0.093
0.104
D
0.330
0.508
0.013
0.020
F
1.194
1.346
0.047
0.053
H
0.229
0.330
0.009
0.013
I
0.102
0.305
0.004
0.012
J
10.008
10.643
0.394
0.419
M
0.381
1.270
0.015
0.050
DS9227A-02 July 2001
Preliminary
DS9227A-02 July 2001
RT9227A
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9
RT9227A
Preliminary
RICHTEK TECHNOLOGY CORP.
RICHTEK TECHNOLOGY CORP.
Headquarter
Taipei Office (Marketing)
6F, No. 35, Hsintai Road, Chupei City
8F-1, No. 137, Lane 235, Paochiao Road, Hsintien City
Hsinchu, Taiwan, R.O.C.
Taipei County, Taiwan, R.O.C.
Tel: (8863)5510047 Fax: (8863)5537749
Tel: (8862)89191466 Fax: (8862)89191465
Email: [email protected]
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10
DS9227A-02 July 2001