L5994 STMicroelectronics, L5994 Datasheet - Page 13

• Manufacturer Part Number: L5994
• Description: IC CTRLR PS ADJ TRPL-OUT 32-TQFP
• Manufacturer: STMicroelectronics

Specifications of L5994

• Pwm Type: Current Mode
• Number Of Outputs: 3
• Frequency - Max: 345kHz
• Duty Cycle: 96%
• Voltage - Supply: 4.75 V ~ 25 V
• Buck: Yes
• Boost: No
• Flyback: Yes
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: No
• Operating Temperature: -40°C ~ 140°C
• Package / Case: 32-TQFP, 32-VQFP
• Frequency-max: 345kHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The 5V regulator is always active, even if both PWM regulators are disabled, as long as power is applied to the
chip.
The 2.5V reference voltage generator, provides comparison levels for threshold detection and device operation.
It is allowed to source up to 5mA to an external load from its buffered output, externally available through pin
VREF.
The reference voltage generator is active if at least one of the two RUNx signal is asserted.
If either PREG5 or VREF does not deliver the correct voltage, the device is shut down.
Figure 6. Controlled timing sequencies
PWROK1
PWROK2
PWROK2
PWROK1
H2GATE
R2GATE
H1GATE
R1GATE
VOUT2
VOUT1
VOUT2
VOUT1
RUN2
RUN1
CRST
RUN2
CRST
RUN1
a) TURN-ON TIMING SEQUENCE
c) SHUTDOWN TIMING SEQUENCE (2)
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PWROK2
PWROK1
H2GATE
R2GATE
H1GATE
R1GATE
H2GATE
R2GATE
H1GATE
R1GATE
PWROK
VOUT2
VOUT1
VOUT2
VOUT1
RUN2
CRST
RUN1
CRST
b) SHUTDOWN TIMING SEQUENCE (1)
d) OVP TIMING SEQUENCE
L5994 - L5994A
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