View RT9002B-PS_4121115.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

RT9002A/B/C
Dual Low-Dropout Regulator with Detector
General Description
The RT9002A/B/C is a dual-channel, low noise, and low dropout regulator. The first regulator is capable of sourcing 240mA, while the second regulator can source up to 500mA and includes a voltage detection function. The RT9002A/B/C performance is optimized for CD/DVD-ROM, CD/RW or wireless communication supply applications. The RT9002A/B/C regulator is stable with output capacitors as low as 1F. The other features include high output accuracy, ultra-fast transient response, tight load and line regulation, current limiting/thermal protection and high ripple rejection ratio. The RT9002A/B/C is available in SOP-8 package requiring minimum board space and smallest components.
Features
Low Quiescent Current (Typically 70A) Wide Operating Voltage Ranges : 2.5V to 5.5V Ultra-Fast Transient Response Tight Load and Line Regulation Current Limiting Protection Thermal Shutdown Protection Only low-ESR Ceramic Capacitors Required for Stability Custom LDO VOUT1, VOUT2 Voltage Available from 1.5V to 3.3V Custom VIN Detector Available from 3.5V to 4.0V RoHS Compliant and 100% Lead (Pb)-Free
Applications Ordering Information
RT9002A/B/C Package Type S : SOP-8 Operating Temperature Range P : Pb Free with Commercial Standard G : Green (Halogen Free with Commercial Standard) Output Voltage : VOUT1/VOUT2 A : 2.5V/3.3V B : 1.5V/2.8V C : 2.5V/3.3V
CD/DVD-ROM, CD/RW Wireless LAN Card/Keyboard/Mouse Battery-Powered Equipment XDSL Router
Pin Configurations
(TOP VIEW)
VIN1 VOUT1 Cd VIN2 2 3 4 8 7 6 5 EN1 GND VDOUT VOUT2
Note :
RichTek Pb-free and Green products are : RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. 100% matte tin (Sn) plating.
SOP-8
Typical Application Circuit
VIN1 1 CIN1 1uF 8 VIN1 VOUT1 2 3 Cd 6 5 COUT2 1uF COUT1 1uF R1 100k VOUT1
RT9002A/B/C Cd EN1 VDOUT
Chip Enable
VIN2 VDOUT VOUT2
VIN2
4 CIN2 1uF
VIN2 GND 7
VOUT2
DS9002ABC-03 March 2007
www.richtek.com 1
RT9002A/B/C
Functional Pin Description
Pin No. 1 2 3 4 5 6 7 8 Pin Name VIN1 VOUT1 Cd VIN2 VOUT2 VDOUT GND EN1 Channel 1 Supply Input. Channel 1 Output Voltage. Delay Capacitor. Channel 2 Supply Voltage. Channel 2 Output Input. Detector Output Voltage. (RT9002A = Active High, RT9002B and RT9002C = Active Low) Common Ground. Chip Enable (Active High) for Channel 1. Pin Function
Function Block Diagram
EN1 Shutdown and Logic Control VREF +
Error Amplifier
VIN1
MOS Driver VOUT1 Current-Limit and Thermal Protection
VIN2
+ Cd
Error Amplifier
MOS Driver Current-Limit and Thermal Protection VOUT2
-
VREF VDOUT +
VD Comparator
GND
www.richtek.com 2
DS9002ABC-03 March 2007
RT9002A/B/C
Absolute Maximum Ratings
(Note 1) Supply Input Voltage -------------------------------------------------------------------------------------------------- 6V Package Thermal Resistance (Note 4) SOP-8, JA -------------------------------------------------------------------------------------------------------------- 110C/W Power Dissipation, PD @ TA = 25C SOP-8 -------------------------------------------------------------------------------------------------------------------- 0.909W Lead Temperature (Soldering, 10 sec.) --------------------------------------------------------------------------- 260C Junction Temperature ------------------------------------------------------------------------------------------------- 150C Storage Temperature Range ---------------------------------------------------------------------------------------- -65C to 150C ESD Susceptibility (Note 2) HBM (Human Body Mode) ------------------------------------------------------------------------------------------ 2kV MM (Machine Mode) -------------------------------------------------------------------------------------------------- 200V
Recommended Operating Conditions
(Note 3)
Supply Input Voltage -------------------------------------------------------------------------------------------------- 2.5V to 5.5V Chip Enable Input Voltage ------------------------------------------------------------------------------------------- 0V to 5.5V Junction Temperature Range ---------------------------------------------------------------------------------------- -40C to 125C Ambient Temperature Range ---------------------------------------------------------------------------------------- -40C to 125C
Electrical Characteristics
(VIN = VOUT + 1V, whichever is greater, CIN = 1F, COUT = 1F, TA = 25C, unless otherwise specified)
Parameter Regulator 1 RT9002A Output Voltage Accuracy RT9002B RT9002C Maximum Output Current Load Regulation Dropout Voltage Quiescent Current Standby Current Line Regulation Power Supply Rejection Rate Current Limit EN Threshold Logic-Low Voltage Logic-High Voltage (Note 5) (Note 6) (Note 7)
Symbol
Test Conditions
Min 2.45
Typ 2.50 1.50 2.50 -1 50 150 30 0.1 0.01 -60 450 --170
Max 2.55 1.53 2.55 -----1 0.2 --0.6 ---
Units
VOUT1 IOUT1_MAX VLOAD1 VDROP1_1 VDROP1_2 IQ1 ISTB1 VLINE1 PSRR1 ILIM1 VIL VIH TSD1
IOUT1 = 30mA
1.47 2.45 240
V mA mV mV A A %/V dB mA V C
1mA < IOUT1 < 100mA IOUT1 = 30mA IOUT1 = 100mA VIN1 = VEN1 = 3.5V, IOUT1 = 0mA VIN1 = 3.5V, VEN1 = 0V VIN1 = 3.5V to 5.5V, VIN1 = VEN1, IOUT1 = 30mA f = 100Hz, IOUT1 = 100mA VIN1 = VEN1 = 5V
---------1.8 --
Thermal Shutdown Protection
To be continued
DS9002ABC-03 March 2007 www.richtek.com 3
RT9002A/B/C
Parameter Thermal Shutdown Hysteresis Enable Pin Current Regulator 2 RT9002A Output Voltage Accuracy RT9002B RT9002C Maximum Output Current Load Regulation Dropout Voltage Quiescent Current Line Regulation Power Supply Rejection Rate Current Limit Thermal Shutdown Protection Thermal Shutdown Hysteresis Detector RT9002A Detect Fall Voltage RT9002B RT9002C Hysteresis RT9002A Sink Current RT9002B RT9002C IDOUT VHYS VDOUT = 0.5V, VIN2 = 5.0V VDOUT = 0.5V, VIN2 = 2.0V VDF 3.528 3.822 3.528 VDF x0.02 7.0 4.0 4.0 3.60 3.9 3.60 VDF x0.05 12.0 8.0 8.0 3.672 3.978 3.672 VDF x0.08 ---mA V V (Note 5) (Note 6) (Note 7) IOUT2_MAX VLOAD2 VDROP2_1 VDROP2_2 IQ2 VLINE2 PSRR2 ILIM2 TSD2 TSD2 1mA < IOUT2 < 100mA IOUT2 = 30mA IOUT2 = 100mA VIN2 = 4.3V, IOUT2 = 0mA VIN2 = 4.3V to 5.5V, IOUT2 = 30mA f = 100Hz, IOUT2 = 100mA VIN2 = 5V VOUT2 IOUT2 = 30mA 3.234 2.744 3.234 500 ---------3.30 2.80 3.30 -15 50 150 40 0.01 -60 800 170 40 3.366 2.856 3.366 -50 90 200 -0.2 ----mA mV mV A %/V dB mA C C V Symbol TSD1 IEN VIN = 3.5V, Enable Test Conditions Min --Typ 40 0.1 Max -1 Units C A
www.richtek.com 4
DS9002ABC-03 March 2007
RT9002A/B/C
Note 1. Stresses listed as the above "Absolute Maximum Ratings" may cause permanent damage to the device. These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. Note 2. Devices are ESD sensitive. Handling precaution recommended. Note 3. The device is not guaranteed to function outside its operating conditions. Note 4. JA is measured in the natural convection at TA = 25C on a high effective thermal conductivity test board of JEDEC 51-7 2S2P 4-layer thermal measurement standard. Note 5. Regulation is measured at constant junction temperature by using a 20ms current pulse. Devices are tested for load regulation in the load range from 1mA to 100mA. Note 6. The dropout voltage is defined as VIN -VOUT, which is measured when VOUT is VOUT(NORMAL) - 100mV. Note 7. Quiescent, or ground current, is the difference between input and output currents. It is defined by IQ = IIN - IOUT under no load condition (IOUT = 0mA). The total current drawn from the supply is the sum of the load current plus the ground pin current.
DS9002ABC-03 March 2007
www.richtek.com 5
RT9002A/B/C
Typical Operating Characteristics
Input Voltage vs. Detector Voltage
7 6
Input Voltage vs. Detector Voltage
7 6
RT9002A
RT9002B
Reset Voltage (V)
Reset Voltage (V)
125 6
5 4 3 2 1 0 0 1 2 3 4 5
5 4 3 2 1 0 0 1 2 3 4 5 6
Input Voltage (V)
Input Voltage (V)
Output Voltage vs. Temperature
3.6 3.4
Output Voltage vs. Temperature
3.0
RT9002A V OUT2
RT9002B
2.8
V OUT2
Output Voltage (V)
3.2 3.0 2.8 2.6 2.4 2.2 -50 -25 0 25 50 75 100 125
Output Voltage (V)
2.6 2.4 2.2 2.0 1.8 1.6 1.4 -50 -25 0 25 50 75 100 125
V OUT1
VOUT1
Temperature (C)
Temperature (C)
Quiescent Current vs. Input Voltage
45 42.5
Quiescent Current vs. Input Voltage
45 42.5
RT9002A
RT9002B
Quiescent Current (uA)
Quiescent Current (uA)
40 37.5 35 32.5 30 27.5 25 2.5 3 3.5 4 4.5 5 5.5
40 37.5 35
VOUT2
V OUT2
V OUT1
32.5 30 27.5 25 2.5 3 3.5 4 4.5 5 5.5
V OUT1
Input Voltage (V)
Input Voltage (V)
www.richtek.com 6
DS9002ABC-03 March 2007
RT9002A/B/C
Nch Driver Sink Current vs. Input Voltage
60
Nch Driver Sink Current vs. Input Voltage
60
RT9002A
Nch Driver Output Current (mA)
Nch Driver Output Current (mA)
-40C 25C
RT9002B -40C
50 40
50 40 30 20 10 0
125C
30 20 10 0 0 1 2 3 4 5 6
25C 125C
0
1
2
3
4
5
6
Input Voltage (V)
Input Voltage (V)
Nch Driver Sink Current vs. VDS
200
Nch Driver Sink Current vs. VDS
110
RT9002A
Nch Driver Output Current (mA)
Nch Driver Output Current (mA)
175 150 125 100 75 50 25 0 0 1 2 3
100 90 80 70 60 50 40 30 20 10 0 0
RT9002B VDD = 3.5V VDD = 3V VDD = 2.5V VDD = 2V VDD = 1.5V VDD = 0.5V
1 2 3 4
VDD = 5V
VDD = 5.5V
VDD = 4.5V
VDD = 1V
5 6
4
5
6
VDS (V)
VDS (V)
Output Delay Time vs. Load Capacitance
1000
Output Delay Time vs. Load Capacitance
1000
RT9002A
RT9002B
Output Delay Time (ms)
10
Output Delay Time (us)
100
100
10
1
1
0.1
0.1
0.01 0.0000
0.0001
0.0010
0.0100
0.1000
0.01 0.0000
0.0001
0.0010
0.0100
0.1000
Load Capacitance (uF)
Load Capacitance (uF)
DS9002ABC-03 March 2007
www.richtek.com 7
RT9002A/B/C
Dropout Voltage vs. Load Current
400 350
Dropout Voltage vs. Load Current
600
RT9002A, VOUT1 = 2.5V 125C 25C
RT9002C, VOUT2 = 3.3V 125C 25C
500
Dropout Voltage (mV)
300 250 200
Dropout Voltage (mV)
400 300
-40C
150 100 50 0 0 50 100 150 200 250 300
-40C
200 100 0 0 0.1 0.2 0.3 0.4 0.5
Load Current (mA)
Load Current (A)
EN Pin Shutdown Response
Shutdown Voltage (5V/Div)
RT9002A, VOUT1 ILOAD = 75mA
Line Transient Response
RT9002A Boost ILOAD = 50mA
VOUT (1V/Div) 4 VOUT1 (20mV/Div) VOUT2 (20mV/Div)
5
VOUT (1V/Div)
Time (100s/Div)
Time (250s/Div)
Load Transient Response
Shutdown Voltage (5V/Div)
RT9002A ILOAD = 10mA to 100mA RT9002A, VOUT1 ILOAD = 75mA
Start Up
IOUT1 (100mA/Div)
VOUT1 (5mV/Div) VOUT2 (50mV/Div)
Time (500s/Div)
VOUT (1V/Div)
Time (10s/Div)
www.richtek.com 8
DS9002ABC-03 March 2007
RT9002A/B/C
Noise
600 400 RT9002B, VOUT1 IOUT1 = 100mA 600 400 RT9002B, VOUT1 No Load
Noise
Noise (V/Div)
200 0 -200 -400 -600
Noise (V/Div)
200 0 -200 -400 -600
Time (10ms/Div)
Time (10ms/Div)
DS9002ABC-03 March 2007
www.richtek.com 9
RT9002A/B/C
Applications Information
Like any low-dropout regulator, the external capacitors used with the RT9002A/B/C must be carefully selected for regulator stability and performance. Using a capacitor whose value is > 1F on the RT9002A/B/C input and the amount of capacitance can be increased without limit. The input capacitor must be located a distance of not more than 0.5 inch from the input pin of the IC and returned to a clean analog ground. Any good quality ceramic can be used for this capacitor. The capacitor with larger value and lower ESR (equivalent series resistance) provides better PSRR and line-transient response. The output capacitor must meet both requirements for minimum amount of capacitance and ESR in all LDOs application. The RT9002A/B/C is designed specifically to work with low ESR ceramic output capacitor in spacesaving and performance consideration. Using a ceramic capacitor whose value is at least 1F with ESR is > 20m on the RT9002A/B/C output ensures stability. The RT9002A/B/C still works well with output capacitor of other types due to the wide stable ESR range. Figure 1. shows the curves of allowable ESR range as a function of load current for various output capacitor values. Output capacitor of larger capacitance can reduce noise and improve load transient response, stability, and PSRR. The output capacitor should be located not more than 0.5 inch from the VOUT pin of the RT9002A/B/C and returned to a clean analog ground. Enable The RT9002A/B/C goes into sleep mode when the Enable pin is in a logic low condition. During this condition, the pass transistor, error amplifier, and bandgap are turned off, reducing the supply current to 0.1A typical. The Enable pin may be directly tied to VIN to keep the part on. The Enable input is CMOS logic and cannot be left floating. PSRR The power supply rejection ratio (PSRR) is defined as the gain from the input to output divided by the gain from the supply to the output. The PSRR is found to be
PSRR = 20 x log Gain Error Supply
Note that when heavy load measuring, supply will cause temperature. And temperature will cause output voltage. So the heavy load PSRR measuring is include temperature effect. Current Limit The RT9002A/B/C contains an independent current limiter, which monitors and controls the pass transistor's gate voltage, limiting the output1/2 current to 0.45/0.8A (typ.). The output can be shorted to ground indefinitely without damaging the part. Thermal-Shutdown Protection Thermal-shutdown protection limits total power dissipation in the RT9002A/B/C. When the junction temperature exceeds TJ = +170C, the thermal sensor signals the shutdown logic, turning off the pass transistor and allowing the IC to cool. The thermal sensor turns the pass transistor on again after the IC's junction temperature cools by 40C, resulting in a pulsed output during continuous thermal overload conditions. Thermal-shutdown protection is designed to protect the RT9002A/B/C in the event of fault conditions. For continual operation, do not exceed the absolute maximum junction temperature rating of TJ = +125C.
Region of Stable COUT ESR vs. Load Current
100
Region of Stable C OUT ESR () Region of Stable COUT ESR ()
10
RT9002APS VIN = 4.0V, VOUT2 = 3.3V CIN = COUT = 1uF/X7R Unstable Region
1
0.1
Stable Region
0.01
Unstable Region (Simulation Verify)
0.001 0 50 100 150 200 250 300
Load Current (mA)
Figure 1
www.richtek.com 10 DS9002ABC-03 March 2007
RT9002A/B/C
Outline Dimension
A
H M
J
B
F
C I D
Dimensions In Millimeters Symbol Min A B C D F H I J M 4.801 3.810 1.346 0.330 1.194 0.170 0.050 5.791 0.400 Max 5.004 3.988 1.753 0.508 1.346 0.254 0.254 6.200 1.270
Dimensions In Inches Min 0.189 0.150 0.053 0.013 0.047 0.007 0.002 0.228 0.016 Max 0.197 0.157 0.069 0.020 0.053 0.010 0.010 0.244 0.050
8-Lead SOP Plastic Package
Richtek Technology Corporation
Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611
Richtek Technology Corporation
Taipei Office (Marketing) 8F, No. 137, Lane 235, Paochiao Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)89191466 Fax: (8862)89191465 Email: marketing@richtek.com
DS9002ABC-03 March 2007
www.richtek.com 11

▲Up To Search▲

Price & Availability of RT9002B-PS

	To Download RT9002B-PS Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .