RT9912A RICHTEK [Richtek Technology Corporation], RT9912A Datasheet
RT9912A
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RT9912A Summary of contents
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... Multi-Channel Power Management IC for Portable Device General Description The RT9912A is a multi-channel power management IC providing power conversion and system power manage- ment functions for one or two alkaline battery powered portable handheld device. The RT9912A integrates one high efficiency synchronous buck regulator, one high efficiency boost regulator, one linear regulator and one adjustable voltage detector for reset function ...
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... RT9912A Typical Application Circuit C1 1uF 22 14 VDD3 C3 1uF 17 C2 1uF VDD3V3_IO R4 120k C4 1nF 20 19, Exposed Pad (25 OUT2 15 Power ON Sequence : V www.richtek.com 2 RT9912A 1 24 VDD1 VOUT1 L1 4.7uH 23 LX1 VBAT 2 FB1 VDD3 D1 4 VDD4 PSW 12 VOUT3 FB4 13 FB3 21 PGND1 8 PGND2 CT 10 PVDD2 ...
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... Syn-Boost PVDD1 PFM PGND1 CH1 Power Ready CH2 Syn-Buck PFM LDOOK CH3 LDO VDD3 Regulator FB3 ENLDO VDD4 CH4 Reset Reset Signal Delay Thermal Protection RT9912A VOUT1 LX1 PGND1 PSW PVDD2 PVDD2 PGND2 LX2 PVDD2 PGND2 PGND2 VOUT3 FB3 RESET CT www.richtek.com 3 ...
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... RT9912A Functional Pin Description Pin No. Pin Name 1 VDD1 2 FB1 3 ENSW 4 PSW ENBST 7 FB2 8 PGND2 9 LX2 10 PVDD2 11 VDD2 12 VOUT3 13 FB3 14 VDD3 15 ENBUK 16 RESET 17 VDD4 18 FB4 19, GND Exposed Pad (25 PGND1 22 VBAT 23 LX1 24 VOUT1 www.richtek.com 4 Pin Function CH1 Power Input Pin. ...
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... V = 3.3V, V DD2 FB2 ENBST ENSW I VDD2 DD1 DD3 (no switching) Min Typ -- -- -- 0.8 1.7 -- 1.7 -- 2.5 -- 1 0. DD4 = 0. DD4 RT9912A − 0.3V to 6.5V − 0.3V to 6.5V − 0.3V to 6.5V − 65°C to 150°C Max Units 1 140 continued www.richtek.com 5 ...
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... RT9912A Parameter LDO Supply Current Voltage Detector Supply Current Feedback Voltage (CH1, CH2) Feedback Voltage Line Regulation of Feedback Voltage of CH1 Power Switch CH1 On Resistance of MOSFET CH1 Current Limitation (Note 5) CH2 On Resistance of MOSFET CH2 Current Limitation Voltage Detector Feedback Voltage Threshold Hysteresis ...
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... DS9912A-01 April 2011 Symbol Test Condition V = 2.8V DD1 BAT BAT T SD Δ 25° high effective four layers thermal conductivity test board of A Handling precaution is recommended. RT9912A Min Typ 0 0 160 -- the expose pad for the package. JC Max ...
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... RT9912A Typical Operating Characteristics CH1 Efficiency vs. Output Current 100 0.001 0.01 Output Current (A) CH1 Output Voltage vs. Output Current 3.40 3.35 3.30 3.25 3.20 3.15 3.10 0 0.05 0.1 0.15 Output Current (A) CH2 Output Voltage vs. Output Current 1.90 1.85 1.80 1.75 1.70 1.65 1.60 1.55 1.50 0 0.05 0.1 0.15 Output Current (A) www.richtek.com 2. 1. 3.3V OUT 3.3V OUT 0 ...
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... Time (5ms/Div) DS9912A-01 April 2011 3.3V OUT I = 200mA OUT 4.3 4.55 4.8 5.05 5.3 FB4 (200mV/Div) RESET (1V/Div DD4 RT9912A CH3 Output Voltage vs. Temperature 3.3 3.2 3.1 3.0 2.9 2.8 V 2.7 -40 - Temperature (°C) LDO Dropout Voltage vs. Output Current 400 350 300 250 200 150 100 ...
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... RT9912A Application Information RT9912A is a four-channel power management IC (PMIC) including one step-up DC-DC converter (Boost), one step- down DC-DC converter (Buck), one low dropout regulator (LDO) and one voltage detector. For optimizing the application of portable hand-held system with one or two alkaline battery, several special logics are designed in this chip ...
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... R2 To place the resistor-divider as close as possible to chip can reduce noise sensitivity. Voltage Detector The RT9912A integrates a voltage detector with push-pull output. The voltage detector senses VDD3V3_IO through a resistor divider and compares it with internal 0.3V reference voltage. When the sensed voltage is lower than the reference voltage, the RESET pin output logic low signal for system access ...
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... Layout Considerations For the best performance of the RT9912A, the following PCB Layout guidelines must be strictly followed. is the maximum A is 54° C/W on the JA = 25°C can be calculated and thermal J(MAX) 2.0 1 ...
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... FB pin and keep away from noisy devices. Figure 3. PCB Layout Guide V PGND VDD3V3_IO BAT C4 PGND C2 GND FB4 18 VDD4 17 VDD3V3_IO RESET 16 ENBUK 15 VDD3 FB3 PGND R5 GND V OUT3 3.3V C9 C12 OUT1 PGND Connect the exposed pad to a ground plane. RT9912A www.richtek.com 13 ...
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... RT9912A Outline Dimension Symbol Richtek Technology Corporation Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 Information that is provided by Richtek Technology Corporation is believed to be accurate and reliable. Richtek reserves the right to make any change in circuit design, specification or other related things if necessary without notice at any time ...