Overview
The TPS3808G15DBVT is a microprocessor supervisory circuit from Texas Instruments, 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. This device is part of the TPS3808 family, which offers adjustable delay times and high threshold accuracy, making it suitable for a wide range of applications, including battery-powered devices and high-reliability systems.
Key Specifications
| Parameter | Test Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| VDD (Input supply range) | –40°C < TJ < 125°C | 1.7 | 6.5 | V | |
| IDD (Supply current) | VDD = 3.3 V, RESET not asserted, MR, RESET, CT open | 2.4 | 5 | μA | |
| VOL (Low-level output voltage) | 1.3 V ≤ VDD < 1.8 V, IOL = 0.4 mA | 0.3 | V | ||
| VIT (Negative-going input threshold accuracy) | VIT ≤ 3.3 V | –1.5% | ±0.5% | 1.5% | % |
| VHYS (Hysteresis on VIT pin) | Fixed versions | 1% | 2.5% | % | |
| Temperature range | –40°C | 125°C | °C | ||
| Package | SOT-23 (6), WSON (6) |
Key Features
- Power-on reset generator with adjustable delay time: 1.25 ms to 10 s
- Very low quiescent current: 2.4 μA typical
- High threshold accuracy: 0.5% typical 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
- Open-drain RESET output
- Small SOT-23 and 2-mm × 2-mm WSON packages
- User-adjustable reset delay time using an external capacitor
- Immunity to short negative transients on the SENSE pin
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 primary function of the TPS3808G15DBVT?
The primary function is 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.
- What is the typical quiescent current of the TPS3808G15DBVT?
The typical quiescent current is 2.4 μA.
- How can the reset delay time be adjusted?
The reset delay time can be adjusted by connecting the CT pin to VDD for a 300-ms delay, leaving the CT pin open for a 20-ms delay, or using an external capacitor for a user-defined delay between 1.25 ms and 10 s.
- What is the temperature range for the TPS3808G15DBVT?
The device is fully specified over a temperature range of –40°C to 125°C.
- What types of packages are available for the TPS3808G15DBVT?
The device is available in SOT-23 and 2-mm × 2-mm WSON packages.
- How accurate is the threshold voltage for the TPS3808G15DBVT?
The threshold accuracy is typically ±0.5% for VIT ≤ 3.3 V.
- Can the TPS3808G15DBVT monitor any voltage rail?
The device can monitor voltage rails from 0.4 V to 5 V, with adjustable and fixed threshold options.
- What is the purpose of the MR pin on the TPS3808G15DBVT?
The MR pin is used for manual reset, allowing the user to assert a RESET signal by driving the MR pin low.
- How does the TPS3808G15DBVT 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 is the recommended practice for the SENSE input to reduce sensitivity to transients?
It is recommended to use a 1-nF to 10-nF bypass capacitor on the SENSE input to reduce sensitivity to transients and layout parasitics.
