ISL6719 Datasheet, PDF (8/9 Pages) Intersil Corporation – 100V Linear Bias Supply

ISL6719
If the application requires high currents or longer start-up
times than the thermal protection allows, the device
dissipation may be reduced by adding a resistor or resistors
in series between the input voltage and VPWR. The
dropping resistance must be selected such that VPWR
remains above the UVLO threshold of VPWR and at least
6.2V greater than VSW under maximum load and minimum
input voltage to maintain regulation.
VIN
1 _{VPWR GND} 9
ENABL ⁸
E_N
2 _AUXEINNABLE 7
3 _VSWCOMPB 6
4 _{VSW_CFOBMPA} 5
FIGURE 7. ADDING DROPPING RESISTORS TO VPWR
ENABLE, ENABLE_N
ENABLE and ENABLE_N are complementary inputs used to
turn VSW on and off. Both polarities of the enable function
are provided to ease the interface to the application. VSW
may be enabled by either ENABLE or ENABLE_N, but both
inputs must be logically false to disable the output. Each
enable input has a nominal 100kΩ pull-up resistor to 5V.
TABLE 1. ENABLE, ENABLE_N TRUTH TABLE
INPUTS
OUTPUT
ENABLE
ENABLE_N
VSW
0
0
ON
0
1
OFF
1
0
ON
1
1
ON
The inputs can accept voltages up to 6V maximum down to
0.3V below signal ground. Voltages beyond these limits,
including transients, may cause permanent damage to the
device. Care should be taken when connecting signal
sources through long connections or if significant ground
shift could occur between the source and the input. In such
circumstances, it is recommended that appropriate clamping
networks be used to prevent possible electrical overstress.
Over-Temperature Protection
The ISL6719 has an over-temperature shutdown
mechanism to protect the device from excessive dissipation.
VSW shutdown occurs approximately at +150°C. The
hysteresis is large so that the IC has sufficient time to
operate at start-up loading levels without re-triggering the
over-temperature protection.
8
FN6555.1
October 1, 2007