Overview
The TPS3808G18DBVT is a low-quiescent-current, programmable-delay supervisory circuit produced by Texas Instruments. This device is part of the TPS3808 family, designed to monitor system voltages and assert a RESET signal when the voltage drops below a preset threshold or when the manual reset (MR) pin is driven low. The TPS3808G18DBVT is particularly suited for applications requiring precise voltage monitoring and adjustable reset delay times, making it ideal for battery-powered and low-power systems.
Key Specifications
| Parameter | Typical Value | Unit |
|---|---|---|
| Quiescent Current (Iq) | 2.4 | μA |
| Threshold Accuracy (VIT ≤ 3.3 V) | ±0.5% | % |
| Threshold Voltage Range | 0.4 V to 5 V | V |
| Reset Delay Time Range | 1.25 ms to 10 s | s |
| Temperature Range | –40°C to 125°C | °C |
| Package Type | SOT-23 (6-pin) | |
| Package Dimensions | 2.90 mm x 1.60 mm x 1.2 mm | mm |
Key Features
- Power-on reset generator with adjustable delay time from 1.25 ms to 10 s
- Very low quiescent current of 2.4 μA typical, making it suitable for battery-powered applications
- High threshold accuracy of ±0.5% for VIT ≤ 3.3 V
- Fixed threshold voltages for standard voltage rails from 0.9 V to 5 V and adjustable voltage down to 0.4 V
- Manual reset (MR) input and open-drain RESET output
- Small SOT-23 and 2-mm × 2-mm WSON packages
- Temperature range of –40°C to 125°C
Applications
- DSP or microcontroller applications
- Notebook and desktop computers
- PDAs and hand-held products
- Portable and battery-powered products
- FPGA and ASIC applications
Q & A
- What is the typical quiescent current of the TPS3808G18DBVT?
The typical quiescent current is 2.4 μA.
- What is the range of the reset delay time for the TPS3808G18DBVT?
The reset delay time can be adjusted from 1.25 ms to 10 s.
- What are the available package types for the TPS3808G18DBVT?
The device is available in SOT-23 (6-pin) and 2-mm × 2-mm WSON packages.
- What is the temperature range for the TPS3808G18DBVT?
The device operates over a temperature range of –40°C to 125°C.
- How can the reset delay time be adjusted?
The reset delay time can be adjusted by connecting the CT pin to VDD using a resistor, leaving the CT pin open, or connecting an external capacitor to the CT pin.
- What is the purpose of the manual reset (MR) input?
The manual reset (MR) input allows for manual assertion of the RESET signal by driving the MR pin low.
- What is the significance of the high threshold accuracy of the TPS3808G18DBVT?
The high threshold accuracy ensures reliable and precise voltage monitoring, which is critical in many applications.
- How does the TPS3808G18DBVT handle short negative transients on the SENSE pin?
The device is relatively immune to short negative transients on the SENSE pin, with sensitivity dependent on threshold overdrive.
- What are the recommended layout guidelines for the TPS3808G18DBVT?
Ensure low-impedance connections to the VDD pin, use a 0.1-µF ceramic capacitor near the VDD pin, and minimize parasitic capacitance on the CT pin.
- Can the TPS3808G18DBVT be used to monitor any voltage rail down to 0.405 V?
Yes, the TPS3808G01 can be used to monitor any voltage rail down to 0.405 V using an external resistor divider.
