The TPS51200DRC is a 3A sink\/source DDR termination regulator from Texas Instruments in a VSON-10 (3×3 mm) package with exposed thermal pad. It generates the VTT bus termination voltage for DDR, DDR2, DDR3, DDR3L, LPDDR3, and DDR4 memory systems. Key features include VLDOIN range 1.1V-3.5V, \u00b110 mA buffered REFOUT (VTTREF), remote sensing (VOSNS), droop compensation, PGOOD monitoring, EN-controlled S3 discharge, soft-start, UVLO, OCL, and thermal shutdown. Requires only 20 \u00b5F minimum output capacitance (3 x 10 \u00b5F MLCCs). Operating range: -40\u00b0C to +85\u00b0C. Green and Pb-free rated, MSL-2.<\/p>","protected":false},"excerpt":{"rendered":"
The TPS51200DRC is a 3A sink\/source DDR termination regulator from Texas Instruments in a VSON-10 (3×3 mm) package with exposed thermal pad. It generates the VTT bus termination voltage for DDR, DDR2, DDR3, DDR3L, LPDDR3, and DDR4 memory systems. Key features include VLDOIN range 1.1V-3.5V, \u00b110 mA buffered REFOUT (VTTREF), remote sensing (VOSNS), droop compensation, […]<\/p>\n","protected":false},"author":2,"featured_media":1886,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[13,29],"tags":[],"chip_brand":[138],"class_list":["post-1823","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-integrated-circuits-ics","category-power-management-ics-pmic","chip_brand-ti"],"acf":{"brief_explanation":"Sink\/source DDR termination regulator, DDR\/DDR2\/DDR3\/DDR4 VTT, 3A, VSON-10 (3x3 mm)","date_code":"","package_case":"VSON-10 (3 x 3 mm)","in_stock":10766,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/tps51200.pdf","price":"$0.90 (1K+ pcs)","product_introduction":"The TPS51200DRC is a sink and source Double Data Rate (DDR) termination regulator manufactured by Texas Instruments, specifically designed for low input voltage, low-cost, low-noise systems where space is a key consideration. It maintains a fast transient response and requires a minimum output capacitance of only 20 \u00b5F (typically 3 x 10 \u00b5F MLCCs), making it one of the most compact and cost-effective VTT regulation solutions available.\n\nThe device integrates a high-performance low-dropout (LDO) linear regulator capable of both sourcing and sinking current up to 3 A, making it ideal for DDR memory bus termination applications. The output voltage (VO) tracks the reference input (REFIN) voltage, which can be connected directly to the memory supply voltage (VDDQ) or through a resistor divider, providing flexibility for DDR, DDR2, DDR3, DDR3L, LPDDR3, and DDR4 VTT applications.\n\nKey features include a VLDOIN voltage range of 1.1V to 3.5V supporting both 2.5V and 3.3V power rails, a \u00b110 mA buffered reference output (REFOUT) for generating the VTTREF reference voltage used by DDR memory controllers, remote voltage sensing (VOSNS) for tight regulation at the load, built-in droop compensation, soft-start current limiting, undervoltage lockout (UVLO), overcurrent protection (OCL), and thermal shutdown.\n\nThe TPS51200 provides an open-drain PGOOD signal to monitor output regulation status and an EN (enable) input that can be used to discharge VTT during S3 (suspend-to-RAM) state for DDR power management. The DRC package is a thermally efficient 10-pin VSON (Very thin Small Outline No-lead) with exposed thermal pad, measuring 3.00 x 3.00 mm. The device operates from -40\u00b0C to +85\u00b0C and is rated both Green and Pb-free.","working_principle":"The TPS51200DRC operates as a bidirectional (sink\/source) linear termination voltage regulator, generating the VTT bus termination voltage for DDR memory systems.\n\nOutput Voltage Regulation: The output voltage (VO) is regulated to match the reference input (REFIN). For standard DDR termination, REFIN is typically connected to a resistor divider from VDDQ (the memory supply voltage) such that REFIN = VDDQ \/ 2. The internal error amplifier compares the sensed output voltage (via VOSNS) against the REFIN-derived reference, driving the pass element to source or sink current as needed to maintain VO = VDDQ \/ 2. This half-VDDQ tracking is the standard VTT voltage required by DDR memory specifications.\n\nSink and Source Capability: Unlike unidirectional LDO regulators, the TPS51200 can both source current (when VTT load demands more current, e.g., driving DQ lines LOW) and sink current (when VTT load returns current, e.g., driving DQ lines HIGH). This bidirectional capability is essential for DDR termination, where the termination resistors connected to VTT must both absorb and supply current depending on the data bus state. The integrated high-side and low-side pass elements enable this sink\/source operation without external components.\n\nDroop Compensation: The device includes built-in droop compensation that pre-adjusts the output voltage slightly higher under heavy sink conditions and slightly lower under heavy source conditions. This anticipatory compensation counteracts the parasitic resistance in PCB traces and vias, maintaining tighter effective regulation at the DDR DIMM termination point.\n\nReference Output (REFOUT): The REFIN voltage is buffered and output on the REFOUT pin, providing a \u00b110 mA buffered reference voltage (VTTREF) for DDR memory controllers. REFOUT becomes active when REFIN exceeds 0.390V and VIN is above the UVLO threshold. When REFOUT drops below 0.375V, it is disabled and discharged to GND through an internal 10 k\u03a9 MOSFET. A 0.1 \u00b5F ceramic capacitor to GND is required on REFOUT for stability. REFOUT operation is independent of the EN pin state.\n\nSoft-Start Sequencing: At startup, a current clamp implements soft-start by limiting the output current to a low constant value, allowing the output capacitors to charge linearly. This prevents inrush current spikes that could damage the device or cause system voltage rail droops. Once the output reaches the target voltage, the current clamp is released and the regulator enters normal operation.\n\nS3\/S5 Power State Support: The EN pin serves dual purpose: when HIGH, the VO regulator is enabled; when LOW (connected to SLP_S3 signal), the VO regulator is disabled and VTT is discharged through an internal MOSFET to GND. This discharge path ensures VTT returns to 0V during suspend-to-RAM (S3) state, meeting DDR power sequencing requirements. REFOUT remains active during S3 state as it is independent of EN.\n\nPower Good (PGOOD): The open-drain PGOOD output goes HIGH-impedance (after a 1 ms deglitch delay) when VO is within \u00b15% of the target voltage, indicating proper regulation. PGOOD goes LOW (asserted) when VO is out of regulation, during UVLO, during thermal shutdown, or when EN is LOW.\n\nProtection Mechanisms: UVLO disables the device when VIN drops below the threshold (approximately 2.1V), preventing erratic operation during power-up\/power-down. Overcurrent protection (OCL) limits the output current to prevent damage during fault conditions. Thermal shutdown disables the device when junction temperature exceeds approximately 150\u00b0C, with automatic recovery when temperature drops.","pin_description":"
| Pin<\/th> | Name<\/th> | Type<\/th> | Default Function<\/th> | Description<\/th><\/tr><\/thead> | ||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1<\/td> | REFIN<\/td> | I<\/td> | Reference Input<\/td> | Sets the target output voltage; connect to VDDQ\/2 via resistor divider or directly; range 0.5V to 1.8V<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| 2<\/td> | VLDOIN<\/td> | I<\/td> | LDO Supply Input<\/td> | Power supply for the LDO regulator; range 1.1V to 3.5V; connect to VDDQ or VDD for DDR3\/DDR4<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| 3<\/td> | VO<\/td> | O<\/td> | LDO Output<\/td> | Termination voltage output (VTT); source\/sink up to 3A; connect to DDR termination bus<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| 4<\/td> | PGND<\/td> | G<\/td> | Power Ground<\/td> | Power ground for the LDO; connect to thermal pad and system GND<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| 5<\/td> | VOSNS<\/td> | I<\/td> | Voltage Sense Input<\/td> | Remote sensing of output voltage; connect to positive terminal of output capacitor or load for tight regulation<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| 6<\/td> | REFOUT<\/td> | O<\/td> | Reference Output<\/td> | Buffered reference output (VTTREF); \u00b110 mA drive; requires 0.1 \u00b5F ceramic cap to GND; max total cap 0.47 \u00b5F<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| 7<\/td> | EN<\/td> | I<\/td> | Enable Input<\/td> | Enable\/disable control; connect to SLP_S3 for DDR VTT control; LOW = VO disabled and discharged<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| 8<\/td> | GND<\/td> | G<\/td> | Signal Ground<\/td> | Signal ground reference<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| 9<\/td> | PGOOD<\/td> | O<\/td> | Power Good<\/td> | Open-drain output; HIGH-Z when VO in regulation (\u00b15%); requires external pull-up resistor<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| 10<\/td> | VIN<\/td> | I<\/td> | Power Supply<\/td> | 2.5V or 3.3V main power supply; requires 1 \u00b5F to 4.7 \u00b5F ceramic decoupling capacitor<\/td><\/tr> | ||||||||||||||||||||||||||||||||||||
| Pad<\/td> | Thermal Pad<\/td> | G<\/td> | Thermal\/PGND<\/td> | Exposed thermal pad; connect to PGND and system GND plane for heat dissipation<\/td><\/tr><\/tbody><\/table>","application_scenarios":"
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