XR76108 Datasheet, PDF (3/17 Pages) Exar Corporation – 8A and 12A Synchronous Step Down COT Regulator

XR76108 and XR76112
Parameter
Min. Typ. Max. Units
IVIN, VIN supply current (XR76108)
6
mA
IOFF, Shutdown current
0.5
μA
Enable and Under-Voltage Lock-Out UVLO
VIH_EN, EN Pin Rising Threshold 1.8 1.9 2.0
V
VEN_HYS, EN Pin Hysteresis
50
mV
VIH_EN, EN Pin Rising Threshold
for DCM/CCM operation
2.8
3.0
3.1
V
VEN_HYS, EN Pin Hysteresis
100
mV
VCC UVLO start threshold,
rising edge
4.00 4.25 4.40 V
VCC UVLO Hysteresis
150 230
mV
Reference voltage
0.597 0.600 0.603 _V
VREF, Reference voltage
0.596 0.600 0.604 _V
0.594 0.600 0.606 _V
DC load regulation
DC Line regulation
±0.25
%
±0.1
%
Parameter
Min. Typ. Max. Units
Programmable Constant On-Time
On-Time 1
1.66 1.95
f corresponding to On-Time 1 243 280
Minimum Programmable On-
Time
109
On-Time 2
162 202
f corresponding to On-Time 2 1217 1361
f corresponding to On-Time 2 369 413
On-Time 3
352 422
Minimum Off-Time
250
Diode Emulation Mode
Zero crossing threshold
-2
Soft-Start
SS Charge current
-14 -10
SS Discharge current
1
3
VCC Linear Regulator
VCC Output Voltage
4.8 5.0
4.3 4.37
Power Good Output
Power Good Threshold
-10 -7.5
Power Good Hysteresis
2
Power Good Sink Current
1
15
Protection: OCP, OTP, Short-Circuit
Hiccup timeout
110
ILIM pin source current
45
50
ILIM current temperature
coefficient
0.4
ILIM comparator offset
-8
0
Current limit blanking
100
Thermal shutdown threshold
150
Thermal Hysteresis
15
Feedback pin short-circuit
threshold
50
60
2.24
329
226
1698
514
492
350
-6
5.2
-5
4
55
+8
70
µs
kHz
ns
ns
kHz
kHz
ns
ns
mV
µA
mA
V
%
%
mA
ms
µA
%/°C
mV
ns
°C
°C
%
Conditions
f=300kHz, RON=107k, VFB=0.58V
Enable=0V, VIN=12V, VIN=PVIN
•
•
•
•
VIN=4.5V-22V  VCC regulating or in dropout
VIN=4.5V-5.5V  VCC tied to VIN
• ^{VIN=4.5V-22V  VCC regulating or in dropout,}
VIN=4.5V-5.5V  VCC tied to VIN
CCM operation, closed loop, applies to any COUT
Conditions
• RON=140kΩ, VIN=22V
VIN=22V, VOUT=12V
RON=6.98kΩ, VIN=22V
• RON=6.98kΩ, VIN=12V
VOUT=3.3V
VOUT=1.0V
• RON=16.2kΩ, VIN=12V
•
DC value measured during test
•
• Fault present
• VIN=6V to 22V, Iload=0 to 30mA
• VIN=4.5V, RON=16.2kΩ, fsw=678kHz, XR76112
•
Rising temperature
• ^{Percent of VREF, short circuit is active}
After PGOOD is up
© 2013-2014 Exar Corporation
3/17
www.exar.com
Rev. 2A