Rainbow Electronics MAX8775 - Manual (Page 3)

MAX8775
Dual and Combinable Graphics Core
Controller for Notebook Computers
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ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V IN = 12V, SKIP_ = PGND = AGND, ON_ = V
CC = 5V, separate mode, T A = 0°C to +85°C, unless otherwise
noted. Typical values are at T A = +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
50 %
SMPS1 to SMPS2 Phase Shift SMPS2 starts after SMPS1
180 Deg
I SLEW_ During transition 4.0 4.75 5.5
Slew-Rate Current
I SLEWSS_ Startup and shutdown 0.70 0.95 1.20
µA
CURRENT LIMIT
Current-Limit Threshold V
LIMIT
V
CSH
_ - V
CSL
_ 26 30 34 mV
Current-Limit Threshold
(Negative)
V NEG V CSH _ - V CSL _ , SKIP_ = V
CC -43 -36 -29 mV
Current-Limit Threshold
(Zero Crossing)
V ZX V CSH _ - V CSL _ , SKIP_ = GND 3 mV
Idle Mode™ Threshold I MIN V CSH _ - V CSL _ , SKIP_ = GND 3.6 6 8.4 mV
REFERENCE (REF)
T A = +25°C to +85°C 2.482 2.50 2.518
Reference Voltage V REF
V CC = 4.5V to 5.5V,
I REF = 0 T
A
= 0°C to +85°C 2.475 2.50 2.525
V
Refer ence S our ce Load Reg ul ati on ΔV
REF I REF = 0µA to 250µA 0.25 1.5 mV
Reference Sink Load Regulation I REF = -50µA 6 mV
REF Lockout Voltage V R E F ( U V L O) Rising edge, hysteresis = 100mV 2.3 V
CURRENT BALANCE
Current-Balance Amplifier (GMI)
Offset
[V(CSH1,CSL1) - V(CSH2,CSL2)] at I CCI = 0 -2 +2 mV
Current-Balance Amplifier (GMI)
Transconductance
ΔI
CCI / Δ[V(CSH1,CSL1) - V(CSH2,CSL2)],
V CCI = V OUT = 0.5V to 2.5V, and
V(CSH_,CSL_) = -60.0mV to +60.0mV
200 µS
FAULT DETECTION
OVP_ Adjust Range V OVP_ 0.5 2.5 V
Outp ut Over vol tag e Tr i p Thr eshol d
Rising edge measured at CSL_,
with respect to OVP_ set voltage
180 200 220 mV
Output Overvoltage Fault
Propagation Delay
t OVP 50mV overdrive 10 µs
Output Undervoltage Protection
Trip Threshold Falling edge measured at CSL_,
with respect to error comparator threshold
-325 300 -275 mV
Output Undevoltage Fault
Propagation Delay
t UVP 50mV overdrive 10 µs
Output Undervoltage Protection
Blanking Time
t BLANK From rising edge of ON_ 6144 1/f SW
PGOOD_ Lower Trip Threshold
Falling edge measured at CSL_,
with respect to error comparator threshold,
hysteresis = 1%
-180 -150 -120 mV
PGOOD_ Propagation Delay t PGOOD _ Falling edge, 50mV overdrive 10 µs
Idle Mode is a trademark of Maxim Integrated Products, Inc.