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List of Material
Proper sequencing is ensured in the design with the use of simple circuits involving the use of NPN
transistors as required. Core 1.2 V at 600 mA comes first ,which in turn is level-shifted to input voltage
using NPN transistors to enable the DCDC3_EN ; hence, static 1.2 V + VRTC at 251 mA comes up which
also enable the DCDC2_EN and sequentially static 1.8 V at 230 mA comes up. This 1.8-V output from
DCDC2 converter enable the LDO and hence at last static 3.3 V at 115 mA comes up.
(1) Use three such LDOs to power up DVDDA, DVDDB, and DVDDC. (It can either be 1.8 V or 3.3 V.)
(2) Rx = 0.499 MΩ, Ry = 1 MΩ for Vout = 1.8 V
(3) Rx = 1.8 MΩ, Ry = 1 MΩ for Vout = 3.3 V
(4) For proper sequencing of output, enable of the LDOs are fed either from 1.2-V output from DCDC3 converter
if DVDDX is 1.8 V or from 1.8-V output from DCDC2 converter if DVDDX is 3.3 V.
Figure 2. Optional circuit for DVDD_A, DVDD_B and DVDD_C
4 List of Material
Table 1. PMP4977 List of Material
Count RefDes Value Description Size Part Number MFR Area
8 C1 10 mF Capacitor, Ceramic, 6.3V, X5R, 10% 805 C2012X5R0J106K TDK 10560
C2 10 mF Capacitor, Ceramic, 6.3V, X5R, 10% 805 C2012X5R0J106K TDK 10560
2 C3 2.2 F Capacitor, Ceramic, 6.3V, X5R, 10% 603 C1608X5R0J225K TDK 5650
C4 2.2 F Capacitor, Ceramic, 6.3V, X5R, 10% 603 C1608X5R0J225K TDK 5650
C5 10 F Capacitor, Ceramic, 6.3V, X5R, 10% 805 C2012X5R0J106K TDK 10560
C6 10 F Capacitor, Ceramic, 6.3V, X5R, 10% 805 C2012X5R0J106K TDK 10560
4 C7 1.0 F Capacitor, Ceramic, 6.3V, X5R,10% 603 C1608X5R0J105K TDK 5650
C8 1.0 F Capacitor, Ceramic, 6.3V, X5R,10% 603 C1608X5R0J105K TDK 5650
C9 10 F Capacitor, Ceramic, 6.3V, X5R, 10% 805 C2012X5R0J106K TDK 10560
C10 10 F Capacitor, Ceramic, 6.3V, X5R, 10% 805 C2012X5R0J106K TDK 10560
C11 1.0 F Capacitor, Ceramic, 6.3V, X5R,10% 603 C1608X5R0J105K TDK 5650
1 C12 1500 pF Capacitor, Ceramic, 50V, X7R, 10% 603 C1608X7R1H152K TDK 5650
2 C13 2.2 F Capacitor, Ceramic, 6.3V, X5R,10% 603 C1608X5R0J225K TDK 5650
C14 2.2 F Capacitor, Ceramic, 6.3V, X5R,10% 603 C1608X5R0J225K TDK 5650
C15 10 F Capacitor, Ceramic, 6.3V, X5R, 10% 805 C2012X5R0J106K TDK 10560
C16 10 F Capacitor, Ceramic, 6.3V, X5R, 10% 805 C2012X5R0J106K TDK 10560
C17 1.0 F Capacitor, Ceramic, 6.3V, X5R,10% 603 C1608X5R0J105K TDK 5650
3 J1 PTC36SAAN Header, 2 pin, 100mil spacing, (36-pin strip) 0.100 x 2 PTC36SAAN Sullins 23100
1 J2 PEC36SAAN Header, Male 5-pin, 100mil spacing, (36-pin 0.100 inch x 5 PEC36SAAN Sullins 60000
strip)
J3 PTC36SAAN Header, 2 pin, 100mil spacing, (36-pin strip) 0.100 x 2 PTC36SAAN Sullins 23100
1 J4 PTC36SAAN Header, 4 pin, 100mil spacing, (36-pin strip) 0.100 x 4 PTC36SAAN Sullins 45100
J5 PTC36SAAN Header, 2 pin, 100mil spacing, (36-pin strip) 0.100 x 2 PTC36SAAN Sullins 23100
1 J6 22-05-3041 Header, Friction Lock Ass'y, 4 pin Right 0.400 x 0.500 22-05-3041 Molex 227,900
Angle
2 L1 2.2 mH Inductor, SMT, 1.72A, 59 mΩ 0.157 x 0.157 inch VLCF4020T-2R2N1R7 TDK 36.8
L2 2.2 mH Inductor, SMT, 1.72A, 59 mΩ 0.157 x 0.157 inch VLCF4020T-2R2N1R7 TDK 36.8
5
SLVA340A–June 2009–Revised May 2010 High-Integration, High-Efficiency Power Solution Using DC/DC Converters With
DVFS
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