Device description

L9958

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DocID17269 Rev 6

3

Device description

3.1

Supply range

The L9958 has an operating supply range from "Vs_uv" (battery monitoring) up to 28 V.

However, the device is tested until 16 V; the functionality of the device is guaranteed until

28 V. The absolute maximum rating is defined to 40 V DC.

3.2

Control inputs

The bridge is controlled by the Inputs PWM, DIR, EN and DI.

All the digital inputs and outputs of the L9958 are compatible with 3.3 V and 5 V CMOS. The

power stages output OUT1 and OUT2 are controlled by the direct inputs DIR and PWM as

given in Table 5. The DIR input gives the direction of output current, while the PWM input

controls whether the current is increased or reduced.

3.2.1

DI and EN inputs

The pin DI is internally pulled-up and high active. When DI is active (set to HIGH), the bridge

is set to tristate, whatever the state of the DIR and PWM inputs. All the data stored in SPI

registers are not reset and SPI communication with the MCU is still possible. When DI is

inactive (set to LOW), the bridge is controlled by the DIR and PWM inputs.

The pin EN is internally pulled down and high active. When EN is inactive (set to LOW), the

bridge is set to tri-state, whatever the state of the DIR and PWM inputs. All the data stored in

SPI registers are not reset and SPI communication with the MCU is still possible. When EN

is active (set to HIGH), the bridge is controlled by the DIR and PWM inputs. The coding is

performed as shown in the next table. The state of the bridge is transferred in the diagnostic

register in a bit called "ACT".

Table 5. Control pins EN, DI

EN

DI

Bit “ACT”

Bridge status

0

0

0

Tri-state

0

1

0

Tri-state

1

0

1

On-state

1

1

0

Tri-state