BD9109FVM-TR Rohm Semiconductor, BD9109FVM-TR Datasheet - Page 19

• Manufacturer Part Number: BD9109FVM-TR
• Description: IC REG SW 0.8A 3.3VOUTPUT 8-MSOP
• Manufacturer: Rohm Semiconductor
• Type: Step-Down (Buck)r
• Series: -r

Specifications of BD9109FVM-TR

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 3.3V
• Current - Output: 800mA
• Frequency - Switching: 1MHz
• Voltage - Input: 4.5 ~ 5.5 V
• Operating Temperature: -25°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Power - Output: 587.4mW
• Output Voltage: 3.3 V
• Output Current: 0.8 A
• Input Voltage: 4.5 V to 5.5 V
• Switching Frequency: 1 MHz
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

●Description of operations
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BD9106FVM,BD9107FVM,BD9109FVM,BD9110NV,BD9120HFN
www.rohm.com
V
V
OUT
EN
・Soft-start function
・Shutdown function
・UVLO function
・Short-current protection circuit with time delay function
CC
*Soft Start time(typ.)
*Timer Latch time (typ.)
※
EN terminal shifted to “High” activates a soft-starter to gradually establish the output voltage with the current limited
during startup, by which it is possible to prevent an overshoot of output voltage and an inrush current.
With EN terminal shifted to “Low”, the device turns to Standby Mode, and all the function blocks including reference
voltage circuit, internal oscillator and drivers are turned to OFF. Circuit current during standby is 0 μF (Typ.).
Detects whether the input voltage sufficient to secure the output voltage of this IC is supplied. And the hysteresis width
of 50～300 mV (Typ.) is provided to prevent output chattering.
Turns OFF the output to protect the IC from breakdown when the incorporated current limiter is activated continuously for the
fixed time(T
T
LATCH
In addition to current limit circuit, output short detect circuit is built in on BD9109FVM and BD9120HFN. If output voltage fall below
2V(typ, BD9109FVM) or Vout×0.5(typ,BD9120HFN), output voltage will hold turned OFF.
Standby mode
V
Limit
OUT
EN
LATCH
Tss
I
L
Standby
mode
BD9106FVM
) or more. The output thus held tuned OFF may be recovered by restarting EN or by re-unlocking UVLO.
UVLO
EN
1
BD9106FVM
Tss
Fig.91 Short-current protection circuit with time delay timing chart
Operating mode
3
BD9107FVM
Soft start
Fig.90 Soft start, Shutdown, UVLO timing chart
Operating mode
1
BD9107FVM
1
Standby
UVLO
mode
BD9109FVM
BD9109FVM
19/28
Tss
2
Hysteresis 50～300mV
Operating mode
1
1msec
Timer latch
BD9110NV
Standby
Output OFF
latch
BD9110NV
mode
Standby
1
mode
EN
5
EN
Tss
Operating mode
Operating mode
BD9120HFN
BD9120HFN
2
1
Technical Note
2009.05 - Rev.A
UVLO
Standby mode
msec
Unit
msec
Unit