Overview
The TPS3808G12DBVTG4, produced by Texas Instruments, is a low-quiescent-current, programmable-delay supervisory circuit designed to monitor system voltages and generate a power-on reset signal. This device is part of the TPS3808 family, which is tailored for microprocessor and microcontroller applications. It features 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 | 2.4 | 5 | μA |
| VOL (Low-level output voltage) | 1.3 V ≤ VDD < 1.8 V, IOL = 0.4 mA | 0.3 | V | ||
| VOL (Low-level output voltage) | 1.8 V ≤ VDD ≤ 6.5 V, IOL = 1 mA | 0.4 | 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% | % | |
| R_MR (MR Internal pullup resistance) | 70 | 90 | kΩ | ||
| ISENSE (Input current at SENSE pin) | VSENSE = VIT | –25 | 25 | nA | |
| Temperature Range | –40°C | 125°C | °C | ||
| Package | SOT-23 (6-pin) |
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
- Temperature range: –40°C to 125°C
- Small SOT-23 and 2-mm × 2-mm WSON packages
- User-adjustable reset delay time using an external capacitor
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 TPS3808G12DBVTG4?
The primary function is to monitor system voltages and generate a power-on reset signal when the voltage drops below a preset threshold or when the manual reset (MR) is driven low.
- What is the range of the adjustable delay time for the RESET signal?
The adjustable delay time ranges from 1.25 ms to 10 s.
- What is the typical quiescent current of the TPS3808G12DBVTG4?
The typical quiescent current is 2.4 μA.
- What are the available package options for the TPS3808G12DBVTG4?
The device is available in SOT-23 and 2-mm × 2-mm WSON packages.
- How can the reset delay time be adjusted?
The reset delay time can be adjusted by connecting the CT pin to VDD, leaving it open, or using an external capacitor.
- What is the temperature range for the TPS3808G12DBVTG4?
The temperature range is from –40°C to 125°C.
- Can the TPS3808G12DBVTG4 monitor any voltage rail?
Yes, it can monitor any voltage rail down to 0.405 V using an external resistor divider.
- What is the hysteresis on the VIT pin?
The hysteresis on the VIT pin is typically 1% to 2.5% for fixed versions.
- How does the device 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 internal pullup resistance of the MR pin?
The internal pullup resistance of the MR pin is typically 70 kΩ to 90 kΩ.
