RT9725A RICHTEK [Richtek Technology Corporation], RT9725A Datasheet
RT9725A
Related parts for RT9725A
RT9725A Summary of contents
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... Express Card Power Interface Switch General Description The RT9725A/B power distribution switches are designed to fulfill power management requirements of Express Card specification. The RT9725A/B supports systems with single slot ExpressCard|34 and ExpressCard|54 socket. The device distributes 3.3V, AUX and 1.5V to the Express Card socket. Each power rail is protected with current limit circuitry when output load exceeds over-current threshold or short-circuits occurs ...
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... Switched output that delivers 0V,3.3V or high impedance to card. No Internal Connection. System reset input-active low, logic level signal, Internal pulled up to AUXIN for RT9725A or floating for RT9725B. Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation. ...
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... Function Block Diagram AUXIN 3.3VIN 1.5VIN CPUSB CPPE STBY SHDN GND DS9725A/B-01 April 2011 Current Limit Current Limit Current Limit UVLO Gate Control AUXIN OTP Charge Pump Oscillator RT9725A Only RT9725A/B Power Good AUXIN Delay AUXOUT 3.3VOUT 1.5VOUT FLG RCLKEN PERST SYSRST www.richtek.com 3 ...
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... RT9725A/B Operation Input Power (1) AUXIN 3.3VIN 1.5VIN Off Off On ON >> Off (1) For Power Input : “On” means the respective input voltage is higher than its turn on threshold voltage; “Off” means the input voltage is lower than its UVLO falling threshold voltage. (for AUX input, “Off ” means the voltage is close to 0V). (2) For Output : “ ...
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... Output are unloaded (Include CPPE and CPUSB logic pull-up current) Q_15 Q _AUX CPPE CPUSB SHDN_33 discharge FETs are on SHDN_15 CPPE, CPUSB and SHDN pull-up current) SHDN _AUX RT9725A 0V, PERST, FLG, RCLKEN are open, CPPE CPUSB Min Typ -- 120 = 1mA ...
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... RT9725A/B Parameter Power Switch I I Forward Leakage Current I I Reverse Leakage Current Thermal Shutdown T ΔT Logic Selection (SHDN, STBY, CPPE, CPUSB, SYSRST, PERST, FLG, RCLKEN Logic Input Supply Current Logic Input Voltage V RCLKEN Output Low Voltage PERST Assertion ...
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... C = 0.1uF, 1.5VOUT 1.5OUT 1.5VIN to 1.5VOUT 100μF, 1.5VOUT /0.5A LOAD_1.5 1.5VIN AUXIN to AUXOUT 0.1μ AUXOUT AUXOUT AUXIN to AUXOUT 100μF, AUXOUT /0.25A LOAD_AUX AUXIN RT9725A/B Min Typ Max Unit -- 0.2 0.4 V μ 2.6 2.75 2.9 1 1.125 1.25 V 2.6 2.75 2.9 -- 100 ...
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... RT9725A/B Note 1. Stresses beyond those listed under These are stress ratings only, and 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 affect device reliability. ...
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... When Card Removed SYSRST (2V/Div) PERST (2V/Div) When Power is On 3.3VOUT (5V/Div) AUXOUT (5V/Div) 1.5VOUT (2V/Div) AUXIN (5V/Div) RT9725A/B Power On Time (2.5ms/Div) PERST Asserted by SYSRST When Power is On Time (500ns/Div) Power Off from AUXIN R = 3.6Ω 2.7Ω, L(3.3OUT) L(1.5OUT 12Ω, C L(AUXOUT) L(3 ...
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... RT9725A/B Power Off from 1.5VIN R = 3.6Ω, R L(3.3OUT 12Ω, C L(AUXOUT) 3.3VOUT (5V/Div) AUXOUT (5V/Div) 1.5VOUT (2V/Div) 1.5VIN (2V/Div) Time (500μs/Div) AUXIN Switch R DS(ON) 140 135 130 125 120 115 110 100 125 150 175 200 225 250 275 Output Current (mA) 1 ...
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... Shutdown Current vs. Temperature 100 -50 3.3VOUT Current Limit vs. Temperature 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 -40 RT9725A/B No Load 3.3VIN 1.5VIN - Temperature (°C) 3.3VIN 1.5VIN - Temperature (°C) - Temperature (°C) www.richtek.com 100 100 80 11 ...
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... RT9725A/B 1.5VOUT Current Limit vs. Temperature 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 -40 -20 0 Temperature (°C) 3.3VIN UVLO Threshold vs. Temperature 3.4 3.2 3.0 2.8 2.6 2.4 2.2 2.0 -40 - Temperature (°C) FLG Delay Time vs. Temperature 13.0 12.5 12.0 11.5 11.0 10.5 10.0 9.5 9.0 -40 -20 0 Temperature (°C) www.richtek.com Rising Falling 100 AUXIN UVLO Threshold vs. Temperature 3.4 3.2 3.0 2.8 2.6 2.4 2.2 2.0 -40 - Temperature (°C) 1.5VIN UVLO Threshold vs. Temperature 2 ...
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... ExpressCard slot the card is inserted prior to the removal of the primary power (either +3 +1 both) at the input of the ExpressCard power switch, then only the primary power (both +3.3 V and +1 removed and the auxiliary power is sent to the ExpressCard slot. RT9725A/B www.richtek.com 13 ...
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... RT9725A/B Express Card Timing Diagrams Host Power (AUXIN / 3.3VIN / 1.5VIN) SYSRST CPUSB / CPPE Card Power (AUXOUT / 3.3VOUT / 1.5VOUT) RCLKEN PERST Host Power (AUXIN / 3.3VIN / 1.5VIN) SYSRST CPUSB / CPPE Card Power (AUXOUT / 3.3VOUT / 1.5VOUT) RCLKEN PERST Host Power (AUXIN) Host Power (3.3VIN / 1.5VIN) ...
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... Card Power (AUXOUT / 3.3VOUT / 1.5VOUT) RCLKEN PERST DS9725A/B-01 April 2011 a c Figure 4. Host Controlled Power Down Figure 5. Controlled Power Down when SHDN Asserted Figure 6. Surprise Card Removal RT9725A/B Tpd Min Max b System a Dependent Load b Dependent c -- 500 500 ...
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... RT9725A/B Thermal Considerations For continuous operation, do not exceed absolute maximum operation junction temperature. The maximum power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surroundings airflow and temperature difference between junction to ambient. The maximum power dissipation can be calculated by following formula : − ...
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... W-Type 20L QFN 3x3 Package Richtek Technology Corporation Taipei Office (Marketing) 5F, No. 95, Minchiuan Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)86672399 Fax: (8862)86672377 Email: marketing@richtek.com RT9725A DETAIL A Pin #1 ID and Tie Bar Mark Options Dimensions In Inches Min Max 0.028 ...