Symbol

Parameter

Test Condition

Min.

Typ.

Max.

Unit

CHARACTERISTICS FOR I

LOW Level Input Voltage

1.5

V

HIGH Level Input Voltage

3

V

Input Hysteresis

0.2

V

LOW Level Output

Sink Current = 3mA

Sink Current = 6mA

0.4

0.6

V

V

Input Current

0.4V

-10

10

µA

SCL Clock Frequency

400

kHz

ELECTRICAL CHARACTERISTICS (continued)

FUNCTIONAL DESCRIPTION

The three high side drivers are a 2.0A output

(HSD1), and two 450mA outputs (HSD2 & 3). The

five regulator outputs are a 10V at 350mA

(REG1), an 8.5V at 175mA (REG2), a 5V at

350mA (REG3), an 8V/10V at 1A (REG4), and 5V

at 250mA (REG5). The regulators are low drop-

out. The regulators will operate with output ca-

pacitors with ESR of 0.1

Ω to 5Ω.

The 8.5V regulator output (REG2) is a tighter tol-

erance output than the other regulator outputs.

The 8.5V output is a

±2.5% (5% total range) out-

put over temperature. This is required on the

regulator to improve performance and reduce

cost on the 8.5V driven IC’s in the radio. The

tighter tolerance is possible by performing a trim

of the bandgap reference to the 8.5V output. The

other outputs are

±5% variation over temperature.

REG3 is referenced from the VREF input not the

internal bandgap. This is done to minimize the

voltage offset between individual 5V supplies.

The REG2 and REG3 outputs are turned on and

off with the Enable input, a ’1’ turns the outputs on

and a ’0’ turns them off. When Enable is "1", the

other outputs can be independently controlled via

the I

must be guaranteed to be lower than 0.2V. The

output voltage of REG4 is selected via bit 5 of the

I

while 10V is the output voltage when bit5 = ’1’.

When all outputs are turned off the total current

draw must be minimized. I

speed range of 100kHz to 400kHz. This device

should be capable of operating at any frequency

within this range.

Protection

The L5950 can survive under the following condi-

tions: shorting the outputs to BAT and GND, loss

of BAT, loss of IC GND, double battery(+26.5V),

4000V ESD, 34V load dump. L5950 will not han-

dle a reverse battery condition. External compo-

nents must be implemented for reverse battery

protection.

Thermal Shutdown: REG1, REG2, REG3, REG4,

REG5 outputs shutdown at 160°C and return to

normal operation at 130°C. The HSD2 and HSD3

shutdown at 160°C and return to normal opera-

tion at 130°C. The HSD1 with go into thermal

shutdown at 170°C and returns to operation at

120°C.

Current Limiting: each voltage regulator will con-

tain its own current protection.

Short Circuit: If the outputs are short circuited, the

IC will go into current limiting and eventually the

thermal shutdown will kick in. Current limiting will

not disable the outputs.

Overvoltage: The IC will not operate if the BAT

voltage reaches 27V typ. or above.

PS

P

SDA

SCL

Sr

D99AU1007

Figure 1. Definition of Timing on the I

L5950

5/8