®
RT8205A/B/C
High Efficiency, Main Power Supply Controllers for Notebook Computers
General Description
The RT8205A/B/C dual step-down, switch-mode powersupply controller generates logic-supply voltages in battery-powered systems. The RT8205A/B/C includes two pulse-width modulation (PWM) controllers fixed at 5V/ 3.3V or adjustable from 2V to 5.5V. An alternative LGATE1 output LG1_CP can be used for external charge pump (RT8205B). And an optional external charge pump can be monitored through SECFB (RT8205C). This device also features 2 linear regulators providing fixed 5V and 3.3V outputs. The linear regulator each provides up to 70mA output current with automatic linear-regulator bootstrapping to the PWM outputs. The RT8205A/B/C includes on-board power-up sequencing, the power-good output, internal softstart, and internal soft-discharge output that prevents negative voltages on shutdown.
A constant on-time PWM control scheme operates without sense resistor and provides 100ns response to load transients while maintaining a relatively constant switching frequency. The unique ultrasonic mode maintains the switching frequency above 25kHz, which eliminates noise in audio applications. Other features include diodeemulation mode (DEM), which maximizes efficiency in light-load applications, and fixed-frequency PWM mode, which reduces RF interference in sensitive application
Features
zWide Input Voltage Range 6V to 25V
zDual Fixed 5V/3.3V Outputs or Adjustable from 2V to 5.5V, 1.5% Accuracy.
zAlternative LGATE1 Output (LG1_CP) acts as Clock for Charge Pump (RT8205B)
zSecondary Feedback Input Maintains Charge Pump Voltage (RT8205C)
zFixed 3.3V and 5V LDO Output : 70mA
z2V Reference Voltage ±1% : 50μA
zConstant ON-Time Control with 100ns Load Step Response
zFrequency Selectable via TONSEL Setting
zRDS(ON) Current Sensing and Programmable Current Limit combined with Enable Control
zSelectable PWM, DEM, or Ultrasonic Mode
zInternal Soft-Start and Soft-Discharge
zHigh Efficiency up to 97%
z5mW Quiescent Power Dissipation
zThermal Shutdown
zRoHS Compliant and Halogen Free
Applications
zNotebook and Sub-Notebook Computers
z3-Cell and 4-Cell Li+ Battery-Powered Devices
Ordering Information
RT8205
Package Type
QW : WQFN-24L 4x4 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Pin Function
A : Default
B : With LG1_CP
C : With SECFB
Note :
Richtek 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.
Copyright ©2012 Richtek Technology Corporation. All rights reserved. |
is a registered trademark of Richtek Technology Corporation. |
DS8205A/B/C-06 July 2012 |
www.richtek.com |
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RT8205A/B/C
Marking Information
RT8205AGQW |
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RT8205BGQW |
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RT8205CGQW |
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CJ= : Product Code |
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CK= : Product Code |
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CL= : Product Code |
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CJ=YM |
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YMDNN : Date Code |
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CK=YM |
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YMDNN : Date Code |
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CL=YM |
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YMDNN : Date Code |
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DNN |
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DNN |
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DNN |
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Pin Configurations
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VOUT1 |
PGOOD |
BOOT1 |
UGATE1 |
PHASE1 |
LGATE1 |
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24 |
23 |
22 |
21 |
20 |
19 |
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ENTRIP1 |
1 |
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18 |
NC |
FB1 |
2 |
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17 |
VREG5 |
REF |
3 |
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GND |
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16 |
VIN |
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TONSEL |
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15 |
GND |
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FB2 |
5 |
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25 |
14 |
SKIPSEL |
ENTRIP2 |
6 |
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13 |
EN |
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7 |
8 |
9 |
10 |
11 |
12 |
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VOUT2 |
VREG3 |
BOOT2 |
UGATE2 |
PHASE2 |
LGATE2 |
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RT8205A |
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WQFN-24L 4x4 |
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(TOP VIEW) |
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VOUT1 |
PGOOD |
BOOT1 |
UGATE1 |
PHASE1 |
LGATE1 |
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24 |
23 |
22 |
21 |
20 |
19 |
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ENTRIP1 |
1 |
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18 |
LG1_CP |
FB1 |
2 |
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17 |
VREG5 |
REF |
3 |
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GND |
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16 |
VIN |
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TONSEL |
4 |
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15 |
PGND |
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FB2 |
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25 |
14 |
SKIPSEL |
ENTRIP2 |
6 |
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13 |
EN |
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7 |
8 |
9 |
10 |
11 |
12 |
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VOUT2 |
VREG3 |
BOOT2 |
UGATE2 |
PHASE2 |
LGATE2 |
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RT8205B |
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WQFN-24L 4x4 |
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VOUT1 |
PGOOD |
BOOT1 |
UGATE1 |
PHASE1 |
LGATE1 |
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24 |
23 |
22 |
21 |
20 |
19 |
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ENTRIP1 |
1 |
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18 |
SECFB |
FB1 |
2 |
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17 |
VREG5 |
REF |
3 |
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GND |
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16 |
VIN |
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TONSEL |
4 |
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15 |
PGND |
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FB2 |
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25 |
14 |
SKIPSEL |
ENTRIP2 |
6 |
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13 |
EN |
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7 |
8 |
9 |
10 |
11 |
12 |
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VOUT2 |
VREG3 |
BOOT2 |
UGATE2 |
PHASE2 |
LGATE2 |
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RT8205C |
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WQFN-24L 4x4 |
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Typical Application Circuit
For Fixed Voltage Regulator
C1 |
R7 |
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3.9 |
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10uF |
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C6 |
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0.1uF |
V |
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L1 |
OUT1 |
6.8uH |
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5V |
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C3 |
R5 |
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220uF |
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C4 |
Q1 |
R4 0 |
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BSC119 |
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N03S |
R3 |
0 |
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C2 |
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0.1uF |
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Q3
BSC119
N03S
C11 0.22uF
Frequency Control
PWM/DEM/Ultrasonic
ON
OFF
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RT8205A |
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16 |
VIN |
UGATE2 |
10 |
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BOOT2 |
9 |
21 |
UGATE1 |
PHASE2 |
11 |
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22 |
BOOT1 |
LGATE2 |
12 |
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V |
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IN |
R9 |
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C9 |
C8 |
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0 |
Q2 |
10uF |
10uF |
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BSC119 |
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R8 |
0 |
N03S |
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C7 |
L2 |
V |
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0.1uF |
4.7uH |
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OUT2 |
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Q4 |
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3.3V |
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R10 |
C13 |
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BSC119 |
220uF |
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N03S |
C10 |
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20 PHASE1
19 LGATE1
24 VOUT1
3REF
4TONSEL
14 SKIPSEL
13 EN
2 FB1
5 FB2
VOUT2 7 VREG5 17
PGOOD 23 VREG3 8
ENTRIP1 1
ENTRIP2 6
C5 |
5V Always On |
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R6 |
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4.7uF |
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100k |
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PGOOD Indicator |
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C12 |
3.3V Always On |
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R1 |
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4.7uF |
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150k |
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R2 |
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150k |
GND 15, Exposed Pad (25)
Copyright ©2012 Richtek Technology Corporation. All rights reserved. |
is a registered trademark of Richtek Technology Corporation. |
www.richtek.com |
DS8205A/B/C-06 July 2012 |
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RT8205A/B/C |
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V |
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IN |
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C1 |
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R7 |
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RT8205B |
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R9 |
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C13 |
C12 |
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3.9 |
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10uF |
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16 |
VIN |
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UGATE2 |
10 |
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0 |
Q2 |
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10uF |
10uF |
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C10 |
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BSC119 |
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R8 |
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N03S |
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0.1uF |
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BOOT2 |
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R4 0 |
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C7 |
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L2 |
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Q1 |
21 |
UGATE1 |
PHASE2 |
11 |
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0.1uF |
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4.7uH |
V |
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BSC119 |
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OUT2 |
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N03S |
R3 |
0 |
22 BOOT1 |
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12 |
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Q4 |
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3.3V |
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LGATE2 |
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R10 |
C17 |
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C2 |
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BSC119 |
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220uF |
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L1 |
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N03S |
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C14 |
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V |
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0.1uF |
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6.8uH |
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OUT1 |
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20 PHASE1 |
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5V |
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VOUT2 |
7 |
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C3 |
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R5 |
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Q3 |
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19 LGATE1 |
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VREG5 |
17 |
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5V Always On |
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220uF |
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BSC119 |
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C9 |
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C4 |
N03S |
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R6 |
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4.7uF |
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100k |
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24 VOUT1 |
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PGOOD 23 |
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C5 |
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PGOOD Indicator |
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D1 |
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VREG3 8 |
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3.3V Always On |
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C6 |
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0.1uF |
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18 LG1_CP |
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C16 |
R1 |
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D2 |
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4.7uF |
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0.1uF |
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ENTRIP1 |
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150k |
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C7 |
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D3 |
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3 REF |
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0.1uF |
C15 |
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R2 |
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150k |
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D4 |
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0.22uF |
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ENTRIP2 6 |
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C8 |
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BAT254 |
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ON |
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13 EN |
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PGND |
15 |
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0.1uF |
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OFF |
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2 |
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CP |
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FB1 |
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Frequency Control |
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4 TONSEL |
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FB2 |
5 |
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PWM/DEM/Ultrasonic |
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14 SKIPSEL |
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GND |
Exposed Pad (25) |
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V |
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R8 |
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IN |
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C1 |
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RT8205C |
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R10 |
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C13 |
C12 |
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3.9 |
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10uF |
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16 |
VIN |
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UGATE2 |
10 |
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0 |
Q2 |
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10uF |
10uF |
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C10 |
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R9 |
0 |
BSC119 |
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0.1uF |
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BOOT2 |
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N03S |
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R4 0 |
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C11 |
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L2 |
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Q1 |
21 UGATE1 |
PHASE2 |
11 |
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0.1uF |
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4.7uH |
VOUT2 |
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BSC119 |
R3 |
0 |
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3.3V |
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N03S |
22 BOOT1 |
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LGATE2 |
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Q4 |
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R11 |
C17 |
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C2 |
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BSC119 |
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220uF |
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L1 |
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N03S |
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C14 |
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0.1uF |
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OUT1 |
6.8uH |
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20 PHASE1 |
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VOUT2 |
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C3 |
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R5 |
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Q3 |
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19 LGATE1 |
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VREG5 |
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5V Always On |
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220uF |
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BSC119 |
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C9 |
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C4 |
N03S |
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R6 |
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4.7uF |
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24 VOUT1 |
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PGOOD 23 |
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100k |
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C5 |
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PGOOD Indicator |
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D1 |
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3 REF |
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VREG3 |
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C16 |
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3.3V Always On |
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C6 |
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0.1uF |
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D2 |
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C15 |
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4.7uF |
R1 |
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0.1uF |
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0.22uF |
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ENTRIP1 |
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150k |
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C7 |
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D3 |
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2 FB1 |
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0.1uF |
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R2 |
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D4 |
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5 FB2 |
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ENTRIP2 6 |
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150k |
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C8 |
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BAT254 |
R6 |
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TONSEL 4 |
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Frequency Control |
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0.1uF |
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200k |
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18 SECFB |
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SKIPSEL |
14 |
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PWM/DEM/Ultrasonic |
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R7 |
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15 |
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CP |
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39k |
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PGND |
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C18 |
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ON |
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GND |
Exposed Pad (25) |
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13 EN |
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OFF |
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Copyright ©2012 Richtek Technology Corporation. All rights reserved. |
is a registered trademark of Richtek Technology Corporation. |
DS8205A/B/C-06 July 2012 |
www.richtek.com |
3
RT8205A/B/C
For Adjustable Voltage Regulator
V
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V |
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IN |
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C1 |
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R7 |
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RT8205A |
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R9 |
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C9 |
C8 |
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3.9 |
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10uF |
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16 |
VIN |
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UGATE2 10 |
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0 |
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Q2 |
10uF |
10uF |
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C6 |
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BSC119 |
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R8 |
0 |
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N03S |
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0.1uF |
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BOOT2 9 |
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R4 0 |
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C7 |
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L2 |
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Q1 |
21 UGATE1 |
PHASE2 |
11 |
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0.1uF |
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4.7uH |
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VOUT2 |
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BSC119 |
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3.3V |
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N03S |
R3 |
0 |
22 BOOT1 |
LGATE2 12 |
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Q4 |
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R10 |
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C13 |
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C2 |
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BSC119 |
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220uF |
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L1 |
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N03S |
C10 |
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0.1uF |
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V |
OUT1 |
6.8uH |
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20 PHASE1 |
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5V |
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VOUT2 7 |
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C3 |
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Q3 |
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19 |
LGATE1 |
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R5 |
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FB2 5 |
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R13 |
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C17 |
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220uF |
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BSC119 |
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R1 |
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N03S |
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6.5k |
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C4 |
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ENTRIP1 1 |
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150k |
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C16 |
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24 VOUT1 |
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R2 |
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R14 |
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0.1uF |
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C14 |
R11 |
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ENTRIP2 6 |
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150k |
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10k |
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15k |
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2 |
FB1 |
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15, Exposed Pad (25) |
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C15 |
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GND |
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R12 |
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3 |
REF |
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0.1uF |
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C11 |
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VREG5 17 |
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10k |
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5V Always On |
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0.22uF |
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C5 |
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R6 |
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Frequency Control |
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4 TONSEL |
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4.7uF |
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100k |
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PGOOD 23 |
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PWM/DEM/Ultrasonic |
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14 SKIPSEL |
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PGOOD Indicator |
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ON |
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13 EN |
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VREG3 8 |
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C12 |
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3.3V Always On |
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OFF |
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4.7uF |
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V |
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IN |
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C1 |
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R7 |
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RT8205B |
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R9 |
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C13 |
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C12 |
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3.9 |
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10uF |
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16 VIN |
UGATE2 |
10 |
0 |
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Q2 |
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10uF |
10uF |
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C10 |
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BSC119 |
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R8 |
0 |
N03S |
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0.1uF |
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BOOT2 9 |
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R4 0 |
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C7 |
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L2 |
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Q1 |
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21 UGATE1 |
PHASE2 |
11 |
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0.1uF |
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4.7uH |
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VOUT2 |
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BSC119 |
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3.3V |
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N03S |
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R3 |
0 |
22 BOOT1 |
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12 |
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Q4 |
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LGATE2 |
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R10 |
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C17 |
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C2 |
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BSC119 |
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220uF |
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L1 |
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N03S |
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C14 |
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0.1uF |
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OUT1 |
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6.8uH |
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20 PHASE1 |
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7 |
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VOUT2 |
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5V |
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Q3 |
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19 LGATE1 |
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C3 |
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R5 |
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R13 |
C21 |
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220uF |
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BSC119 |
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C4 |
N03S |
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5 |
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6.5k |
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FB2 |
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C20 |
|||
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R1 |
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24 VOUT1 |
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R14 |
0.1uF |
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C18 |
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ENTRIP1 |
1 |
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150k |
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R11 |
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R2 |
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10k |
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15k |
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2 FB1 |
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C19 |
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C5 |
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ENTRIP2 |
6 |
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150k |
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R12 |
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D1 |
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0.1uF |
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0.1uF |
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Exposed Pad (25) |
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10k |
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18 LG1_CP |
GND |
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|||||||
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C6 |
D2 |
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0.1uF |
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17 |
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VREG5 |
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|||
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D3 |
C7 |
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3 |
REF |
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C9 |
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5V Always On |
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0.1uF |
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C15 |
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R6 |
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4.7uF |
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D4 |
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0.22uF |
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100k |
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||
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PGOOD |
23 |
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|||||
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PGOOD Indicator |
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|||||||
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C8 |
BAT254 |
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ON |
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13 EN |
VREG3 |
8 |
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3.3V Always On |
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||||||||
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0.1uF |
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OFF |
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C16 |
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CP |
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4.7uF |
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4 TONSEL |
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|||
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Frequency Control |
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PGND |
15 |
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|||||
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PWM/DEM/Ultrasonic |
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14 SKIPSEL |
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||||||
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|
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|
Copyright ©2012 Richtek Technology Corporation. All rights reserved. |
is a registered trademark of Richtek Technology Corporation. |
www.richtek.com |
DS8205A/B/C-06 July 2012 |
4 |
|
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|
RT8205A/B/C |
||||
|
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V |
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R8 |
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IN |
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C1 |
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RT8205C |
|
R10 |
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C13 |
C12 |
|
||||
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3.9 |
|
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|
||||||||
|
10uF |
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|
16 |
VIN |
UGATE2 |
10 |
|
0 |
Q2 |
|
10uF |
10uF |
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C10 |
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|||||||
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R9 |
0 |
BSC119 |
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|||
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0.1uF |
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|
BOOT2 9 |
N03S |
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||||
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R4 0 |
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C11 |
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L2 |
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Q1 |
21 |
UGATE1 |
|
11 |
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0.1uF |
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|
4.7uH |
|
V |
||
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BSC119 |
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PHASE2 |
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OUT2 |
|||
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R3 |
0 |
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3.3V |
|||
|
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|
N03S |
22 BOOT1 |
LGATE2 |
12 |
|
|
Q4 |
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R11 |
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C17 |
||||
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C2 |
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BSC119 |
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220uF |
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L1 |
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N03S |
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C14 |
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0.1uF |
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VOUT1 |
6.8uH |
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20 PHASE1 |
VOUT2 7 |
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C3 |
R5 |
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Q3 |
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19 LGATE1 |
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R14 |
C21 |
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220uF |
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BSC119 |
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6.5k |
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C4 |
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N03S |
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5 |
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FB2 |
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C20 |
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24 VOUT1 |
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R1 |
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R15 |
0.1uF |
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ENTRIP1 1 |
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150k |
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C18 |
R12 |
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10k |
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15k |
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2 FB1 |
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R2 |
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C19 |
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ENTRIP2 6 |
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150k |
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R13 |
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0.1uF |
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D1 |
C5 |
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GND Exposed Pad (25) |
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10k |
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0.1uF |
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3 |
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C6 |
D2 |
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C15 |
REF |
VREG5 |
17 |
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5V Always On |
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0.1uF |
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C9 |
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C7 |
0.22uF |
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R6 |
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D3 |
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4.7uF |
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0.1uF |
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100k |
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PGOOD 23 |
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D4 |
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PGOOD Indicator |
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C8 |
BAT254 |
R6 |
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VREG3 8 |
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C16 |
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3.3V Always On |
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200k |
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0.1uF |
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18 SECFB |
TONSEL 4 |
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4.7uF |
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R7 |
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Frequency Control |
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CP |
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C18 |
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39k |
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SKIPSEL 14 |
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PWM/DEM/Ultrasonic |
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OFF |
ON |
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13 EN |
PGND 15 |
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Copyright ©2012 Richtek Technology Corporation. All rights reserved. |
is a registered trademark of Richtek Technology Corporation. |
DS8205A/B/C-06 July 2012 |
www.richtek.com |
5
RT8205A/B/C
Function Block Diagram
|
TONSEL |
SKIPSEL |
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BOOT1 |
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BOOT2 |
UGATE1 |
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UGATE2 |
PHASE1 |
VREG5 |
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PHASE2 |
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VREG5 |
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SMPS1 |
SMPS2 |
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LGATE1 |
PWM Buck |
PWM Buck |
LGATE2 |
Controller |
Controller |
||
PGND |
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VOUT1 |
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VOUT2 |
FB1 |
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FB2 |
ENTRIP1 |
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ENTRIP2 |
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Power-On |
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PGOOD |
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EN |
Sequence |
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Clear Fault Latch |
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GND |
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SW Threshold |
SW Threshold |
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Thermal |
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Shutdown |
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VREG5 |
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VREG3 |
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VREG5 |
REF |
VREG3 |
VIN |
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REF |
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Function Block Diagram
TONSEL VIN
UGATE
VOUT |
On-Time |
TON |
Q |
R |
TOFF |
Compute |
1-Shot |
TRIG 1-Shot |
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Q |
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TRIG |
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REF |
- |
+ |
- |
Comp |
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+ |
- |
+ |
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LGATE |
FB |
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Over-Voltage |
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VREG5 |
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1.1 x VREF |
+ |
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Fault |
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- |
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Latch |
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0.7 x VREF |
- |
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Blanking |
+ |
ENTRIP |
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+ |
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Time |
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Under-Voltage |
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- |
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- |
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Current |
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+ Limit |
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0.9 x V |
+ |
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SS |
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REF |
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Time |
- |
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- |
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+ |
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PGOOD |
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25kHz |
+ |
PHASE |
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Detector |
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Zero - |
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Detector |
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SKIPSEL |
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PWM Controller (One Side) |
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Copyright ©2012 Richtek Technology Corporation. All rights reserved. |
|
is a registered trademark of Richtek Technology Corporation. |
||||
www.richtek.com |
|
|
|
|
DS8205A/B/C-06 July 2012 |
6
RT8205A/B/C
Functional Pin Description
ENTRIP1 (Pin 1)
Channel 1 enable and Current Limit setting Input. Connect resistor to GND to set the threshold for channel 1 synchronous RDS(ON) sense. The GND-PHASE1 currentlimit threshold is 1/10th the voltage seen at ENTRIP1 over a 0.5V to 2V range. There is an internal 10uAcurrent source from VREG5 to ENTRIP1. The logic current limit threshold is default to 200mV value if ENTRIP1 is higher than VREG5-1V.
FB1 (Pin 2)
SMPS1 Feedback Input. Connect FB1 to VREG5 or GND for fixed 5V operation. Or connect FB1 to a resistive voltagedivider from VOUT1 to GND to adjust output from 2V to 5.5V.
REF (Pin 3)
2V Reference Output. Bypass to GND with a 0.22uF capacitor. REF can source up to 50uA for external loads. Loading REF degrades FBx and output accuracy according to the REF load-regulation error.
TONSEL (Pin 4)
Frequency Selectable Input for VOUT1/VOUT2 respectively.
400kHz/500kHz : Connect to VREG5 or VREG3
300kHz/375kHz : Connect to REF
200kHz/250kHz : Connect to GND
FB2 (Pin 5)
SMPS2 Feedback Input. Connect FB2 to VREG5 or GND for fixed 3.3V operation. Or connect FB2 to a resistive voltage-divider from VOUT2 to GND to adjust output from 2V to 5.5V.
ENTRIP2 (Pin 6)
Channel 2 enable and Current Limit setting Input. Connect resistor to GND to set the threshold for channel 2 synchronous RDS(ON) sense. The GND-PHASE2 currentlimit threshold is 1/10th the voltage seen at ENTRIP2 over a 0.5V to 2V range. There is an internal 10uAcurrent source
from VREG5 to ENTRIP2. The logic current limit threshold is default to 200mV value if ENTRIP2 is higher than VREG5-1V.
VOUT2 (Pin 7)
SMPS2 Output Voltage-Sense Input. Connect to the SMPS2 output. VOUT2 is an input to the on-time oneshot circuit. It also serves as the SMPS2 feedback input in fixed-voltage mode.
VREG3 (Pin 8)
3.3V Linear Regulator Output.
BOOT2 (Pin 9)
Boost Flying Capacitor Connection for SMPS2. Connect to an external capacitor according to the typical application circuits.
UGATE2 (Pin 10)
High-Side MOSFET Floating Gate-Driver Output for SMPS2. UGATE2 swings between PHASE2 and BOOT2.
PHASE2 (Pin 11)
Inductor Connection for SMPS2. PHASE2 is the internal lower supply rail for the UGATE2 high-side gate driver. PHASE2 is also the current-sense input for the SMPS2.
LGATE2 (Pin 12)
SMPS2 Synchronous-Rectifier Gate-Drive Output. LGATE2 swings between GND and VREG5.
EN (Pin 13)
Master Enable Input. The REF/VREG5/VREG3 are enabled if it is within logic high level and disable if it is less than the logic low level.
SKIPSEL (Pin 14)
Operation Mode Selectable Input.
Ultrasonic Mode : Connect to VREG5 or VREG3
Diode Emulation Mode : Connect to REF
PWM Mode : Connect to GND
Copyright ©2012 Richtek Technology Corporation. All rights reserved. |
is a registered trademark of Richtek Technology Corporation. |
DS8205A/B/C-06 July 2012 |
www.richtek.com |
|
7 |
RT8205A/B/C
GND [Pin 15 (RT8205A), Exposed Pad (25)]
Analog Ground for SMPS controller. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation.
PGND (Pin 15) (RT8205B/C)
Power Ground for SMPS controller. Connect PGND externally to the underside of the exposed pad.
VIN (Pin 16)
High Voltage Power Supply Input for 5V/3.3V LDO and Feed-forward ON-Time circuitry.
VREG5 (Pin 17)
5V Linear Regulator Output.VREG5 is also the supply voltage for the low-side MOSFET driver and analog supply voltage for the device.
NC (Pin 18) (RT8205A)
No Internal Connection.
LG1_CP (Pin 18) (RT8205B)
Alternative LGATE1 Output for 14V charge pump.
SECFB (Pin 18) (RT8205C)
The SECFB is used to monitor the optional external 14V charge pump. Connect a resistive voltage-divider from 14V charge pump output to GND to detect the output. If SECFB drops below the threshold voltage, LGATE1 turns on for 300ns (typ.). This will refresh the external charge pump driven by LGATE1 without over-discharging the output voltage.
LGATE1 (Pin 19)
SMPS1 Synchronous-Rectifier Gate-Drive Output. LGATE1 swings between GND and VREG5.
PHASE1 (Pin 20)
Inductor Connection for SMPS1. PHASE1 is the internal lower supply rail for the UGATE1 high-side gate driver. PHASE1 is also the current-sense input for the SMPS1.
UGATE1 (Pin 21)
High-Side MOSFET Floating Gate-Driver Output for SMPS1. UGATE1 swings between PHASE1 and BOOT1.
BOOT1 (Pin 22)
Boost Flying Capacitor Connection for SMPS1. Connect to an external capacitor according to the typical application circuits.
PGOOD (Pin 23)
Power Good Output for channel 1 and channel 2. (Logical AND)
VOUT1 (Pin 24)
SMPS1 Output Voltage-Sense Input. Connect to the SMPS1 output. VOUT1 is an input to the on-time oneshot circuit. It also serves as the SMPS1 feedback input in fixed-voltage mode.
Copyright ©2012 Richtek Technology Corporation. All rights reserved. |
is a registered trademark of Richtek Technology Corporation. |
www.richtek.com |
DS8205A/B/C-06 July 2012 |
8 |
|
|
RT8205A/B/C |
Absolute Maximum Ratings (Note 1) |
|
z VIN, EN to GND ----------------------------------------------------------------------------------------------- |
−0.3V to 28V |
z PHASEx to GND |
|
DC ---------------------------------------------------------------------------------------------------------------- |
−0.3V to 28V |
< 20ns ---------------------------------------------------------------------------------------------------------- |
−8V |
z BOOTx to PHASEx ------------------------------------------------------------------------------------------ |
−0.3V to 6V |
z ENTRIPx, SKIPSEL, TONSEL, PGOOD, to GND ---------------------------------------------------- |
−0.3V to 6V |
z VREG5, VREG3, FBx, VOUTx, SECFB, REF to GND --------------------------------------------- |
−0.3V to (VREG5 + 0.3V) |
z UGATEx to PHASEx |
|
DC ---------------------------------------------------------------------------------------------------------------- |
−0.3V to (VREG5 + 0.3V) |
< 20ns ---------------------------------------------------------------------------------------------------------- |
−5V |
z LGATEx to GND |
|
DC ---------------------------------------------------------------------------------------------------------------- |
−0.3V to (VREG5 + 0.3V) |
< 20ns ---------------------------------------------------------------------------------------------------------- |
−2.5V |
z Power Dissipation, PD @ TA = 25°C |
|
WQFN-24L 4x4 ----------------------------------------------------------------------------------------------- |
1.923W |
z Package Thermal Resistance (Note 2) |
|
WQFN-24L 4x4, θJA ------------------------------------------------------------------------------------------ |
52°C/W |
WQFN-24L 4x4, θJC ----------------------------------------------------------------------------------------- |
7°C/W |
z Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------ |
260°C |
z Junction Temperature ---------------------------------------------------------------------------------------- |
150°C |
z Storage Temperature Range ------------------------------------------------------------------------------- |
−65°C to 150°C |
z ESD Susceptibility (Note 3) |
|
HBM (Human Body Model) --------------------------------------------------------------------------------- |
2kV |
Recommended Operating Conditions |
(Note 4) |
z Input Voltage, VIN -------------------------------------------------------------------------------------------- |
6V to 25V |
z Junction Temperature Range ------------------------------------------------------------------------------- |
−40°C to 125°C |
z Ambient Temperature Range ------------------------------------------------------------------------------- |
−40°C to 85°C |
Copyright ©2012 Richtek Technology Corporation. All rights reserved. |
is a registered trademark of Richtek Technology Corporation. |
DS8205A/B/C-06 July 2012 |
www.richtek.com |
|
9 |
To be continued