ETC RT9224CS

RT9224
Function Block Diagram
VCC
VSEN
110%
Power-On
Reset (POR)
+
90%
PGOOD
+
-
115%
+
Over Voltage
OVP
Soft
Start
+
OCSET
- Over Current
Reference
VID0
VID1
VID2
VID3
VID4
TTL D/A
Converter
(DAC)
DACOUT
Error Amplifier
+
-
SS
BOOT
UGATE
4.5V
200uA
10uA
PWM
Comparator
+
-
FB
Oscillator
Inhibit
PHASE
Gate
Control
Logic
PWM
LGATE
PGND
GND
DS9224-05 March 2004
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RT9224
Functional Pin Description
Pin No. Pin Name
1
VSEN
Pin Function
Output voltage monitoring input for OVP & PGOOD
Over current set pin, sinks 200µA through a resistor (ROCS) from this pin to upper
N-MOSFET to set the trip point:
2
OCSET
IPEAK =
200uA × ROCS
MOSFET - on resistance
An over-current trip cycles the soft-start function
3
SS
Soft start speed is set by internal 10µA current source and capacitor from this pin to GND
4
VID0
Switching Regulator Output Voltage Setting
5
VID1
Switching Regulator Output Voltage Setting
6
VID2
Switching Regulator Output Voltage Setting
7
VID3
Switching Regulator Output Voltage Setting
8
VID4
Switching Regulator Output Voltage Setting
9
NC
No Connection
10
FB
Feedback input pin for the PWM Loop
11
GND
12
PGOOD
IC Signal Ground
Open Drain Logic Output
This pin is pulled low when the converter output is not within ±10% of the DACOUT
reference voltage
13
PHASE
Current Limit Sense Input
14
UGATE
High Side Driver Output
15
BOOT
Driver Power
16
PGND
Low Side Driver GND
17
LGATE
Low Side Driver Output
18
VCC
Power Supply Input
19
OVP
Over Voltage Protection
This pin is pulled high when the VSEN voltage is over 15% of the DACOUT reference
voltage
20
NC
No Connection
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DS9224-05 March 2004
RT9224
Table 1 Output Voltage Program
Pin Name
VID4 VID3 VID2 VID1 VID0
Nominal Output
Voltage DACOUT
Nominal
Pin Name
VID4 VID3 VID2 VID1 VID0
Output Voltage
DACOUT
0
1
1
1
1
1.30V
1
1
1
1
1
2.0V
0
1
1
1
0
1.35V
1
1
1
1
0
2.1V
0
1
1
0
1
1.40V
1
1
1
0
1
2.2V
0
1
1
0
0
1.45V
1
1
1
0
0
2.3V
0
1
0
1
1
1.50V
1
1
0
1
1
2.4V
0
1
0
1
0
1.55V
1
1
0
1
0
2.5V
0
1
0
0
1
1.60V
1
1
0
0
1
2.6V
0
1
0
0
0
1.65V
1
1
0
0
0
2.7V
0
0
1
1
1
1.70V
1
0
1
1
1
2.8V
0
0
1
1
0
1.75V
1
0
1
1
0
2.9V
0
0
1
0
1
1.80V
1
0
1
0
1
3.0V
0
0
1
0
0
1.85V
1
0
1
0
0
3.1V
0
0
0
1
1
1.90V
1
0
0
1
1
3.2V
0
0
0
1
0
1.95V
1
0
0
1
0
3.3V
0
0
0
0
1
2.00V
1
0
0
0
1
3.4V
0
0
0
0
0
2.05V
1
0
0
0
0
3.5V
DS9224-05 March 2004
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RT9224
Absolute Maximum Ratings
Supply Voltage ------------------------------------------------------------------------------------------------------- +15V
Boot Voltage ---------------------------------------------------------------------------------------------------------- +15V
Input, Output or I/O Voltage --------------------------------------------------------------------------------------- GND -0.3V to Vcc + 0.3V
Storage Temperature Range --------------------------------------------------------------------------------------- −65° C to 150° C
Package Thermal Resistance
SOP-20,θJA ---------------------------------------------------------------------------------------------------------------------------------------------------------- 87° C/W
Recommended Operating Conditions
Supply Voltage, VCC ------------------------------------------------------------------------------------------------------------------------------------------ +12V ±10%
Ambient Temperature Range -------------------------------------------------------------------------------------- 0° C to 70°C
Junction Temperature Range -------------------------------------------------------------------------------------- 0° C to 125°C
Electrical Characteristics
(TA = 25° C, recommended operating conditions, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
UGATE and LGATE Open
--
3
--
mA
VCC Rising Threshold
VOCSET = 4.5V
--
9.5
--
V
VCC Falling Threshold
VOCSET = 4.5V
--
7.5
--
V
--
1.6
--
V
170
200
230
kHz
--
1.9
--
VP-P
DAC (VID0 – VID4) Input Low Voltage
--
--
0.8
V
DAC (VID0 – VID4) Input High Voltage
2.0
--
--
V
DACOUT Voltage Accuracy
-1.0
--
+1.0
%
--
65
--
dB
VCC Supply Current
Nominal Supply
ICC
Power-On Reset
Rising VOCSET Threshold
Oscillator
Free Running Frequency
Ramp Amplitude
∆VOSC
Reference and DAC
Error Amplifier
DC Gain
Gate Drivers
UGATE Source
RUGATE VBOOT - VPHASE = 12V
--
8
--
Ω
UGATE Sink
RUGATE VUGATE - VPHASE = 1V
--
5
--
Ω
LGATE Source
ILGATE
--
500
--
mA
LGATE Sink
RLGATE VLGATE = 1V
--
5
--
Ω
VCC = 12V, VLGATE = 6V
To be continued
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DS9224-05 March 2004
RT9224
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
--
115
120
%
Protection
Over-voltage Trip (VSEN/DACOUT)
OCSET Current Source
IOCSET
VOCSET = 4.5V
167
200
233
µA
OVP Sourcing Current
IOVP
VSEN = 5.5V, VOVP = 0V
60
--
--
mA
Soft-Start Current
ISS
VSS = 1.5V
--
10
--
µA
Power Good
Upper Threshold (VSEN/DACOUT)
VSEN Rising
106
--
114
%
Lower Threshold (VSEN/DACOUT)
VSEN Falling
89
--
96
%
Hysteresis (VSEN/DACOUT)
Upper and Lower Threshold
--
2
--
%
--
0.5
--
V
PGOOD Voltage Low
DS9224-05 March 2004
VPGOOD IPGOOD = -5mA
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RT9224
Outline Dimension
H
A
M
B
J
F
C
I
D
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
12.598
13.005
0.496
0.512
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
20–Lead SOP Plastic Package
RICHTEK TECHNOLOGY CORP.
RICHTEK TECHNOLOGY CORP.
Headquarter
Taipei Office (Marketing)
5F, No. 20, Taiyuen Street, 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)5526789 Fax: (8863)5526611
Tel: (8862)89191466 Fax: (8862)89191465
Email: [email protected]
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DS9224-05 March 2004