ISL6550C
SAM (Supervisor And Monitor)
Typical Diagram
Key Features
- 12V supply operation
- 5V reference output
- 5-bit digital-to-analog converter
- Programmable DAC Range, within 0.8-5.0V
- Programmable undervoltage and overvoltage thresholds, and latched fault detection
- Optional delayed undervoltage (programmable with external capacitor)
- Undervoltage lockout (power-on-reset)
- Status Indicators (START, PGOOD)
- Uncommitted operational amplifier
- Compatible with ISL6551 full bridge controller
- 20 Lead SOIC and 20 lead QFN (5x5) packages
- QFN Package:
- Compliant to JEDEC PUB95 MO-220 QFN - Quad Flat No Leads - Package Outline
- Near Chip Scale Package footprint, which improves PCB efficiency and has a thinner profile
Description
The ISL6550 is a precision, flexible, VID-code-controlled reference and voltage monitor for high-end microprocessor and memory power supplies. It monitors various input signals, and supervises the system (typically a DC/DC converter) with its output signals. See the Block Diagram for reference.
The ISL6550 includes a 5-bit DAC (Digital-to-Analog Converter), which is programmed by the five VID inputs. The voltage range of the BDAC (Buffered DAC output) is determined by the DACHI and DACLO voltage levels, which are externally adjustable through the R1, R2, R3 resistor divider network. VREF5 is a precision-trimmed 5V reference, and is used to set the voltage at the top of the resistor divider.
Programmable window comparators monitor Overvoltage (OV) and Undervoltage (UV) levels. The OVUVSEN input, usually coming from the associated power converter device is monitored and compared with BDAC; an error band is established via the R4 and R5 resistor setting on the OVUVTH pin. An optional external capacitor on the UVDLY pin gives a programmable delay on the UV. A high gain operational amplifier is available at pins VOPP, VOPM, and VOPOUT; it can be used as a gain stage to permit monitoring voltages that are different from the BDAC levels.
The PEN (Power supply ENable) input, driven from an opencollector source, enables (when logic high) the external converter output, via the PGOOD or START outputs (both open-drain). They both basically indicate that the power supply is enabled (PEN = high) and there are no fault conditions. There are two logic options available, which determine the START and PGOOD states; see the block diagram or the Logic Options Table for more detail. The two logic options are identified with a suffix letter A or C in the ordering information.
Applications
- Power Supplies for High End Microprocessors and Servers
- Can be paired with the ISL6551 FBC for a complete fullbridge 48V-input converter, or used independently
