MAX1907A Maxim Integrated Products, MAX1907A Datasheet
MAX1907A
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MAX1907A Summary of contents
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... When any of these protection fea- tures detect a fault, the MAX1907A/MAX1981A immedi- ately shut down. Additionally, the MAX1907A includes overvoltage protection. The MAX1907A/MAX1981A are available in a thin 40-pin QFN package. Applications IMVP-IV™ Notebook Computers Single-Phase CPU Core Supply ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) ABSOLUTE MAXIMUM RATINGS V+ to GND ..............................................................-0.3V to +30V GND .....................................................-0. SYSPOK, IMVPOK, CLKEN to GND .........................-0.3V to +6V DPSLP, SUS, ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V 1.26V, ILIM = V , SUS = D5 = D1= D0 ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V 1.26V, ILIM = V , SUS = D5 = D1= D0 ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V 1.26V, ILIM = V , SUS = D5 = D1= D0 ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) ELECTRICAL CHARACTERISTICS (Circuit of Figure 15V 1.26V, ILIM = V , SUS = ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V 1.26V, ILIM = V , SUS = ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V 1.26V, ILIM = V , SUS = ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) (Circuit of Figure 12V VOLTAGE-POSITIONED OUTPUT vs. LOAD CURRENT (V = 1.436V) OUT 1.46 1.44 1.42 1.40 1.38 1.36 1.34 1.32 ...
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... OUTPUT VOLTAGE (V) VOLTAGE-POSITIONING AMPLIFIER GAIN AND PHASE vs. FREQUENCY GAIN -10 PHASE -20 -30 -40 0 100 1.02 FREQUENCY (kHz 1.265 1.270 MAX1907A/81A toc18 180 144 108 -36 -72 -108 -144 -180 1000 10,000 ...
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... OUT C. DDO, 5V/div D. CLKEN, 5V/div NO LOAD SHUTDOWN SEQUENCE A 0 1.436V 100μs/div 5V, 5V/div SHDN 1.436V to 0, 1V/div OUT C. IMPVOK 5V/div D. CLKEN, 5V/div E. DDO, 5V/div MAX1907A/81A toc21 MAX1907A/81A toc24 ...
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... EXITING DEEP-SLEEP MODE MAX1907A/81A toc27 A 0 1.436V B 1.398V 20μs/div 5V, 5V/div DPSLP 1.398V to 1.436V, 50mV/div OUT C. MAX1907A/MAX1981A LX, 10V/div D. MAX1980 LX, 10V/div SUS = GND 1.0A OUT LOAD TRANSIENT (LOWEST FREQUENCY) MAX1907A/81A toc30 10A A 0 0.844V 20μs/div A ...
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... MAX1907A/81A toc33 0 1.436V 1.308V 0 0 40μs/div 1V, 1V/div 1.436V to 1.308V, 100mV/div OUT 10A/div 10A/div LS (DO = 16mV) MAX1907A/81A toc32 20μs/div 1V, 1V/div 1.436V to 1.420V,, 20mV/div OUT 10A/div 10A/div ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) PIN NAME Boot-Mode Voltage Select Inputs. B0–B2 are four-level digital inputs that select the boot-mode VID code (Table 6) for the boot-mode multiplexer inputs. During power-up, the boot-mode VID ...
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... Sequence section), the decoded state of the four-level B0–B2 inputs set the output voltage. Driver-Disable Output. This TTL-logic output can be used to disable the driver outputs on slave-switching regulator controllers. This forces a high-impedance condition and makes it possible for the MAX1907A/MAX1981A master controller to operate in low current SKIP mode. DDO goes low 32 R DDO 27 clock cycles after the MAX1907A/MAX1981A completes a transition to the suspend mode or deep-sleep voltage (see the Driver Disable and Low-Power Pulse Skipping section) ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) PIN NAME Open-Drain Power Good Output. After output voltage transitions, except during power-up and power-down, if OUT is in regulation then IMVPOK is high impedance. IMVPOK is pulled high ...
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... SYSPOK V+ CLKEN BST IMVPOK C BST(M) 0.1μ PGND S0 S1 GND S2 R22 200Ω MAX1907A B0 CSP MAX1981A C11 B1 1000pF CSN B2 R23 200Ω OAIN+ SUS DPSLP OAIN- R1 SHDN 1.5kΩ 1% TON FB C5 NEG 100pF CC R6 2.74kΩ REF ...
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... MAX1980 PGND ILIM GND CS+ C9 4700pF CS- DD CM+ LIMIT C10 4700pF TRIG CM- 5V BIAS SUPPLY INPUT 24V C IN (3) 10μF 25V CERAMIC N H( OUTPUT N L(S) R18 200Ω R19 200Ω R20 200Ω R21 200Ω CONNECT TO MAX1907A/MAX1981A (SEE FIGURE 1) ...
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... Taiyo Yuden TDK Toko Detailed Description 5V Bias Supply (V The MAX1907A/MAX1981A require an external 5V bias supply in addition to the battery. Typically, this 5V bias supply is the notebook’s 95% efficient 5V system supply. Keeping the bias supply external to the IC improves efficiency and eliminates the cost associated with the 5V linear regulator that would otherwise be needed to supply the PWM circuit and gate drivers ...
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... Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) V+ TON CSP CSN ILIM 0.9 x REF CLKEN POWER-GOOD LOGIC IMVPOK Figure 2. MAX1907A/MAX1981A Functional Diagram 20 ______________________________________________________________________________________ ON-TIME COMPUTE MAX1907A MAX1981A ONE-SHOT Q TRIG MINIMUM ON-TIME OFF-TIME Q TRIG ONE-SHOT FAULT ...
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... POS to NEG. DROP 2 Forced-PWM Operation (Normal Mode) During normal mode, when the CPU is actively running (SUS = low and DPSLP = high), the MAX1907A/ is DROP2 MAX1981A operates with the low-noise, forced-PWM control scheme. Forced-PWM operation disables the ...
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... TIME MAX1907A/MAX1981A enters low-power operation, allowing pulse skipping under light loads. When the CPU pulls SUS low, the MAX1907A/MAX1981A immedi- ately enters forced-PWM operation, forces DDO high, and slews the output up to the operating voltage set by the D0–D5 inputs. When either SUS transition occurs, ...
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... DL driver to the MOSFET gate in order for the adaptive dead-time circuit to work properly. Otherwise, the sense circuitry in the MAX1907A/MAX1981A will interpret the MOSFET gate as “off” while there is actually charge still left on the gate. Use very short, wide traces (50 to 100 mils wide if the MOSFET is 1in from the device) ...
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... MOSFET without degrading the turn-off time (Figure 5). Voltage Positioning Amplifier The MAX1907A/MAX1981A includes a dedicated oper- ational amplifier for adding gain to the voltage position- ing sense path. The voltage positioning gain allows the use of low-value, current-sense resistors in order to minimize power dissipation. This 3MHz gain-bandwidth amplifier was designed with low offset voltage (70µ ...
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... this fashion, the output can be clamped with a Schottky diode to PGND to reduce the negative excursion. When SHDN or SYSPOK goes low, the MAX1907A/ MAX1981A enters low-power shutdown mode. IMVPOK is pulled low and CLKEN is driven high immediately. The output voltage ramps down 16mV steps at the clock rate set by R ...
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... Table 6). Operation with automatic PWM/PFM switchover for pulse skipping under light loads. Fault Mode. The fault latch has been set by either UVP, OVP (MAX1907A only), thermal shutdown falling x 0 GND edge on SYSPOK. The controller will remain in FAULT mode until V ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) Table 5. Output Voltage VID DAC Codes (SUS = Low ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) Table 6. Suspend Mode DAC Codes (SUS = High GND GND GND GND GND REF GND GND OPEN GND GND V CC GND REF GND GND ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) Table 7. Boot-Mode DAC Codes (Power-Up GND GND GND GND GND REF GND GND OPEN GND GND V CC GND REF GND GND REF REF GND ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV S0–S2 DECODER OUT S2 SUS B0–B2 DECODER OUT B2 SYSPOK Figure 7. Internal Multiplexers Functional Diagram 30 ...
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... CPU suspends operation, SUS is driven high, overrid- ing the 6-bit VID DAC code set by D0–D5. The master controller slews the output to the selected suspend- mode voltage. During the transition, the MAX1907A/ MAX1981A asserts forced-PWM operation until 62 R clock cycles after the slew-rate controller reach- TIME es the suspend-mode voltage ...
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... Output Undervoltage Shutdown The output undervoltage protection (UVP) function is similar to foldback current limiting, but employs a timer rather than a variable current limit. If the MAX1907A/MAX1981A output voltage is under 70% of the nominal value, the PWM is latched off and won’t restart until SHDN is toggled or V power is cycled below 1V ...
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... V differentials. OUT balance required for stable multi-phase regulation. When the MAX1907A/MAX1981A limits the master inductor current, the slave’s current-balance circuitry also limits the slave inductor current. However, if the current-balance circuitry fails, the slave controller’s cur- rent limit provides back-up overcurrent protection. ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) In non-CPU applications, the output capacitor’s size often depends on how much ESR is needed to maintain an acceptable level of output ripple voltage. The output ripple voltage of ...
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... OS-CON) are preferred due to their resistance to inrush surge currents typical of systems with a mechanical switch or connector in series with the input. If the MAX1907A/MAX1981A are operated as the second stage of a two-stage power-conversion system, tantalum input capacitors are acceptable. In either con- figuration, choose an input capacitor that exhibits less than +10° ...
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... LOAD VALLEY MAX ( ) ⎝ where I is the maximum “valley” current VALLEY(MAX) allowed by the current-limit circuit, including threshold MAX1907A MAX1981A ERROR COMPARATOR Figure 8. Voltage Positioning Gain 36 ______________________________________________________________________________________ tolerance and on-resistance variation. The MOSFETs H must have a relatively large heatsink to handle the over- load power dissipation ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) The voltage-positioned circuit determines the load current from the voltage across the current-sense resistors ( connected between the inductors SENSE CM CS and output ...
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... The effective efficiency of voltage-positioned circuits is shown in the Typical Operating Characteristics . One-Stage (Battery Input) vs. Two-Stage (5V Input) Applications The MAX1907A/MAX1981A can be used with a direct battery connection (one stage) or can obtain power from a regulated 5V supply (two stage). Each approach has advantages, and careful consideration should go into the selection of the final design ...
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... Figure 11. PC Board Layout Example ______________________________________________________________________________________ 2) Connect all analog grounds to a separate solid cop- per plane, which connects to the GND pin of the MAX1907A/MAX1981A. This includes the V bypass capacitor, REF bypass capacitor, compen- sation (CC) capacitor, and the resistive-dividers connected to ILIM and POS/NEG. ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) the master to the analog ground in the slave to pre- vent ground offsets. A low value (≤10Ω) resistor is sufficient to link the two grounds. 4) Keep the ...
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... Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) MAX1907A MAX1981A (MASTER) CURRENT ACTIVE VOLTAGE POSITIONING CURRENT BALANCE AND CURRENT LIMIT (SLAVE) MAX1980 ______________________________________________________________________________________ 5V BIAS SUPPLY LIMIT TRIGGER Typical Operating Circuit INPUT OUTPUT IMVP-IV CPU 5V BIAS SUPPLY INPUT 41 ...
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Quick-PWM Master Controllers for Voltage- Positioned CPU Core Power Supplies (IMVP-IV) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 42 ______________________________________________________________________________________ Package Information ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 43 © 2002 Maxim Integrated Products ...